Add protobuf 2.2.0a sources

This is the contents of protobuf-2.2.0a.tar.bz2 from
http://code.google.com/p/protobuf/downloads/list and
is the base code for the javamicro code generator.

Change-Id: Ie9a0440a824d615086445b6636944484b3155afa

14 files changed, 8363 insertions, 0 deletions

diff --git a/java/src/test/java/com/google/protobuf/AbstractMessageTest.java b/java/src/test/java/com/google/protobuf/AbstractMessageTest.java
new file mode 100644
index 0000000..2c59fd0
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/AbstractMessageTest.java
@@ -0,0 +1,421 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import protobuf_unittest.UnittestOptimizeFor.TestOptimizedForSize;
+import protobuf_unittest.UnittestProto;
+import protobuf_unittest.UnittestProto.ForeignMessage;
+import protobuf_unittest.UnittestProto.TestAllExtensions;
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestPackedTypes;
+import protobuf_unittest.UnittestProto.TestRequired;
+import protobuf_unittest.UnittestProto.TestRequiredForeign;
+
+import junit.framework.TestCase;
+
+import java.util.Map;
+
+/**
+ * Unit test for {@link AbstractMessage}.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+public class AbstractMessageTest extends TestCase {
+  /**
+   * Extends AbstractMessage and wraps some other message object.  The methods
+   * of the Message interface which aren't explicitly implemented by
+   * AbstractMessage are forwarded to the wrapped object.  This allows us to
+   * test that AbstractMessage's implementations work even if the wrapped
+   * object does not use them.
+   */
+  private static class AbstractMessageWrapper extends AbstractMessage {
+    private final Message wrappedMessage;
+
+    public AbstractMessageWrapper(Message wrappedMessage) {
+      this.wrappedMessage = wrappedMessage;
+    }
+
+    public Descriptors.Descriptor getDescriptorForType() {
+      return wrappedMessage.getDescriptorForType();
+    }
+    public AbstractMessageWrapper getDefaultInstanceForType() {
+      return new AbstractMessageWrapper(
+        wrappedMessage.getDefaultInstanceForType());
+    }
+    public Map<Descriptors.FieldDescriptor, Object> getAllFields() {
+      return wrappedMessage.getAllFields();
+    }
+    public boolean hasField(Descriptors.FieldDescriptor field) {
+      return wrappedMessage.hasField(field);
+    }
+    public Object getField(Descriptors.FieldDescriptor field) {
+      return wrappedMessage.getField(field);
+    }
+    public int getRepeatedFieldCount(Descriptors.FieldDescriptor field) {
+      return wrappedMessage.getRepeatedFieldCount(field);
+    }
+    public Object getRepeatedField(
+        Descriptors.FieldDescriptor field, int index) {
+      return wrappedMessage.getRepeatedField(field, index);
+    }
+    public UnknownFieldSet getUnknownFields() {
+      return wrappedMessage.getUnknownFields();
+    }
+    public Builder newBuilderForType() {
+      return new Builder(wrappedMessage.newBuilderForType());
+    }
+    public Builder toBuilder() {
+      return new Builder(wrappedMessage.toBuilder());
+    }
+
+    static class Builder extends AbstractMessage.Builder<Builder> {
+      private final Message.Builder wrappedBuilder;
+
+      public Builder(Message.Builder wrappedBuilder) {
+        this.wrappedBuilder = wrappedBuilder;
+      }
+
+      public AbstractMessageWrapper build() {
+        return new AbstractMessageWrapper(wrappedBuilder.build());
+      }
+      public AbstractMessageWrapper buildPartial() {
+        return new AbstractMessageWrapper(wrappedBuilder.buildPartial());
+      }
+      public Builder clone() {
+        return new Builder(wrappedBuilder.clone());
+      }
+      public boolean isInitialized() {
+        return clone().buildPartial().isInitialized();
+      }
+      public Descriptors.Descriptor getDescriptorForType() {
+        return wrappedBuilder.getDescriptorForType();
+      }
+      public AbstractMessageWrapper getDefaultInstanceForType() {
+        return new AbstractMessageWrapper(
+          wrappedBuilder.getDefaultInstanceForType());
+      }
+      public Map<Descriptors.FieldDescriptor, Object> getAllFields() {
+        return wrappedBuilder.getAllFields();
+      }
+      public Builder newBuilderForField(Descriptors.FieldDescriptor field) {
+        return new Builder(wrappedBuilder.newBuilderForField(field));
+      }
+      public boolean hasField(Descriptors.FieldDescriptor field) {
+        return wrappedBuilder.hasField(field);
+      }
+      public Object getField(Descriptors.FieldDescriptor field) {
+        return wrappedBuilder.getField(field);
+      }
+      public Builder setField(Descriptors.FieldDescriptor field, Object value) {
+        wrappedBuilder.setField(field, value);
+        return this;
+      }
+      public Builder clearField(Descriptors.FieldDescriptor field) {
+        wrappedBuilder.clearField(field);
+        return this;
+      }
+      public int getRepeatedFieldCount(Descriptors.FieldDescriptor field) {
+        return wrappedBuilder.getRepeatedFieldCount(field);
+      }
+      public Object getRepeatedField(
+          Descriptors.FieldDescriptor field, int index) {
+        return wrappedBuilder.getRepeatedField(field, index);
+      }
+      public Builder setRepeatedField(Descriptors.FieldDescriptor field,
+                                      int index, Object value) {
+        wrappedBuilder.setRepeatedField(field, index, value);
+        return this;
+      }
+      public Builder addRepeatedField(
+          Descriptors.FieldDescriptor field, Object value) {
+        wrappedBuilder.addRepeatedField(field, value);
+        return this;
+      }
+      public UnknownFieldSet getUnknownFields() {
+        return wrappedBuilder.getUnknownFields();
+      }
+      public Builder setUnknownFields(UnknownFieldSet unknownFields) {
+        wrappedBuilder.setUnknownFields(unknownFields);
+        return this;
+      }
+    }
+  }
+
+  // =================================================================
+
+  TestUtil.ReflectionTester reflectionTester =
+    new TestUtil.ReflectionTester(TestAllTypes.getDescriptor(), null);
+
+  TestUtil.ReflectionTester extensionsReflectionTester =
+    new TestUtil.ReflectionTester(TestAllExtensions.getDescriptor(),
+                                  TestUtil.getExtensionRegistry());
+
+  public void testClear() throws Exception {
+    AbstractMessageWrapper message =
+      new AbstractMessageWrapper.Builder(
+          TestAllTypes.newBuilder(TestUtil.getAllSet()))
+        .clear().build();
+    TestUtil.assertClear((TestAllTypes) message.wrappedMessage);
+  }
+
+  public void testCopy() throws Exception {
+    AbstractMessageWrapper message =
+      new AbstractMessageWrapper.Builder(TestAllTypes.newBuilder())
+        .mergeFrom(TestUtil.getAllSet()).build();
+    TestUtil.assertAllFieldsSet((TestAllTypes) message.wrappedMessage);
+  }
+
+  public void testSerializedSize() throws Exception {
+    TestAllTypes message = TestUtil.getAllSet();
+    Message abstractMessage = new AbstractMessageWrapper(TestUtil.getAllSet());
+
+    assertEquals(message.getSerializedSize(),
+                 abstractMessage.getSerializedSize());
+  }
+
+  public void testSerialization() throws Exception {
+    Message abstractMessage = new AbstractMessageWrapper(TestUtil.getAllSet());
+
+    TestUtil.assertAllFieldsSet(
+      TestAllTypes.parseFrom(abstractMessage.toByteString()));
+
+    assertEquals(TestUtil.getAllSet().toByteString(),
+                 abstractMessage.toByteString());
+  }
+
+  public void testParsing() throws Exception {
+    AbstractMessageWrapper.Builder builder =
+      new AbstractMessageWrapper.Builder(TestAllTypes.newBuilder());
+    AbstractMessageWrapper message =
+      builder.mergeFrom(TestUtil.getAllSet().toByteString()).build();
+    TestUtil.assertAllFieldsSet((TestAllTypes) message.wrappedMessage);
+  }
+
+  public void testPackedSerialization() throws Exception {
+    Message abstractMessage =
+        new AbstractMessageWrapper(TestUtil.getPackedSet());
+
+    TestUtil.assertPackedFieldsSet(
+      TestPackedTypes.parseFrom(abstractMessage.toByteString()));
+
+    assertEquals(TestUtil.getPackedSet().toByteString(),
+                 abstractMessage.toByteString());
+  }
+
+  public void testPackedParsing() throws Exception {
+    AbstractMessageWrapper.Builder builder =
+      new AbstractMessageWrapper.Builder(TestPackedTypes.newBuilder());
+    AbstractMessageWrapper message =
+      builder.mergeFrom(TestUtil.getPackedSet().toByteString()).build();
+    TestUtil.assertPackedFieldsSet((TestPackedTypes) message.wrappedMessage);
+  }
+
+  public void testOptimizedForSize() throws Exception {
+    // We're mostly only checking that this class was compiled successfully.
+    TestOptimizedForSize message =
+      TestOptimizedForSize.newBuilder().setI(1).build();
+    message = TestOptimizedForSize.parseFrom(message.toByteString());
+    assertEquals(2, message.getSerializedSize());
+  }
+
+  // -----------------------------------------------------------------
+  // Tests for isInitialized().
+
+  private static final TestRequired TEST_REQUIRED_UNINITIALIZED =
+    TestRequired.getDefaultInstance();
+  private static final TestRequired TEST_REQUIRED_INITIALIZED =
+    TestRequired.newBuilder().setA(1).setB(2).setC(3).build();
+
+  public void testIsInitialized() throws Exception {
+    TestRequired.Builder builder = TestRequired.newBuilder();
+    AbstractMessageWrapper.Builder abstractBuilder =
+      new AbstractMessageWrapper.Builder(builder);
+
+    assertFalse(abstractBuilder.isInitialized());
+    builder.setA(1);
+    assertFalse(abstractBuilder.isInitialized());
+    builder.setB(1);
+    assertFalse(abstractBuilder.isInitialized());
+    builder.setC(1);
+    assertTrue(abstractBuilder.isInitialized());
+  }
+
+  public void testForeignIsInitialized() throws Exception {
+    TestRequiredForeign.Builder builder = TestRequiredForeign.newBuilder();
+    AbstractMessageWrapper.Builder abstractBuilder =
+      new AbstractMessageWrapper.Builder(builder);
+
+    assertTrue(abstractBuilder.isInitialized());
+
+    builder.setOptionalMessage(TEST_REQUIRED_UNINITIALIZED);
+    assertFalse(abstractBuilder.isInitialized());
+
+    builder.setOptionalMessage(TEST_REQUIRED_INITIALIZED);
+    assertTrue(abstractBuilder.isInitialized());
+
+    builder.addRepeatedMessage(TEST_REQUIRED_UNINITIALIZED);
+    assertFalse(abstractBuilder.isInitialized());
+
+    builder.setRepeatedMessage(0, TEST_REQUIRED_INITIALIZED);
+    assertTrue(abstractBuilder.isInitialized());
+  }
+
+  // -----------------------------------------------------------------
+  // Tests for mergeFrom
+
+  static final TestAllTypes MERGE_SOURCE =
+    TestAllTypes.newBuilder()
+      .setOptionalInt32(1)
+      .setOptionalString("foo")
+      .setOptionalForeignMessage(ForeignMessage.getDefaultInstance())
+      .addRepeatedString("bar")
+      .build();
+
+  static final TestAllTypes MERGE_DEST =
+    TestAllTypes.newBuilder()
+      .setOptionalInt64(2)
+      .setOptionalString("baz")
+      .setOptionalForeignMessage(ForeignMessage.newBuilder().setC(3).build())
+      .addRepeatedString("qux")
+      .build();
+
+  static final String MERGE_RESULT_TEXT =
+      "optional_int32: 1\n" +
+      "optional_int64: 2\n" +
+      "optional_string: \"foo\"\n" +
+      "optional_foreign_message {\n" +
+      "  c: 3\n" +
+      "}\n" +
+      "repeated_string: \"qux\"\n" +
+      "repeated_string: \"bar\"\n";
+
+  public void testMergeFrom() throws Exception {
+    AbstractMessageWrapper result =
+      new AbstractMessageWrapper.Builder(
+        TestAllTypes.newBuilder(MERGE_DEST))
+      .mergeFrom(MERGE_SOURCE).build();
+
+    assertEquals(MERGE_RESULT_TEXT, result.toString());
+  }
+
+  // -----------------------------------------------------------------
+  // Tests for equals and hashCode
+  
+  public void testEqualsAndHashCode() throws Exception {
+    TestAllTypes a = TestUtil.getAllSet();
+    TestAllTypes b = TestAllTypes.newBuilder().build();
+    TestAllTypes c = TestAllTypes.newBuilder(b).addRepeatedString("x").build();
+    TestAllTypes d = TestAllTypes.newBuilder(c).addRepeatedString("y").build();
+    TestAllExtensions e = TestUtil.getAllExtensionsSet();
+    TestAllExtensions f = TestAllExtensions.newBuilder(e)
+        .addExtension(UnittestProto.repeatedInt32Extension, 999).build();
+
+    checkEqualsIsConsistent(a);
+    checkEqualsIsConsistent(b);
+    checkEqualsIsConsistent(c);
+    checkEqualsIsConsistent(d);
+    checkEqualsIsConsistent(e);
+    checkEqualsIsConsistent(f);
+    
+    checkNotEqual(a, b);
+    checkNotEqual(a, c);
+    checkNotEqual(a, d);
+    checkNotEqual(a, e);
+    checkNotEqual(a, f);
+
+    checkNotEqual(b, c);
+    checkNotEqual(b, d);
+    checkNotEqual(b, e);
+    checkNotEqual(b, f);
+
+    checkNotEqual(c, d);
+    checkNotEqual(c, e);
+    checkNotEqual(c, f);
+
+    checkNotEqual(d, e);
+    checkNotEqual(d, f);
+
+    checkNotEqual(e, f);
+
+    // Deserializing into the TestEmptyMessage such that every field
+    // is an {@link UnknownFieldSet.Field}.
+    UnittestProto.TestEmptyMessage eUnknownFields =
+        UnittestProto.TestEmptyMessage.parseFrom(e.toByteArray());
+    UnittestProto.TestEmptyMessage fUnknownFields =
+        UnittestProto.TestEmptyMessage.parseFrom(f.toByteArray());
+    checkNotEqual(eUnknownFields, fUnknownFields);
+    checkEqualsIsConsistent(eUnknownFields);
+    checkEqualsIsConsistent(fUnknownFields);
+
+    // Subseqent reconstitutions should be identical
+    UnittestProto.TestEmptyMessage eUnknownFields2 =
+        UnittestProto.TestEmptyMessage.parseFrom(e.toByteArray());
+    checkEqualsIsConsistent(eUnknownFields, eUnknownFields2);
+  }
+  
+  /**
+   * Asserts that the given proto has symetric equals and hashCode methods.
+   */
+  private void checkEqualsIsConsistent(Message message) {
+    // Object should be equal to itself.
+    assertEquals(message, message);
+    
+    // Object should be equal to a dynamic copy of itself.
+    DynamicMessage dynamic = DynamicMessage.newBuilder(message).build();
+    checkEqualsIsConsistent(message, dynamic);
+  }
+
+  /**
+   * Asserts that the given protos are equal and have the same hash code.
+   */
+  private void checkEqualsIsConsistent(Message message1, Message message2) {
+    assertEquals(message1, message2);
+    assertEquals(message2, message1);
+    assertEquals(message2.hashCode(), message1.hashCode());
+  }
+
+  /**
+   * Asserts that the given protos are not equal and have different hash codes.
+   * 
+   * @warning It's valid for non-equal objects to have the same hash code, so
+   *   this test is stricter than it needs to be. However, this should happen
+   *   relatively rarely.
+   */
+  private void checkNotEqual(Message m1, Message m2) {
+    String equalsError = String.format("%s should not be equal to %s", m1, m2);
+    assertFalse(equalsError, m1.equals(m2));
+    assertFalse(equalsError, m2.equals(m1));
+
+    assertFalse(
+        String.format("%s should have a different hash code from %s", m1, m2),
+        m1.hashCode() == m2.hashCode());
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/CodedInputStreamTest.java b/java/src/test/java/com/google/protobuf/CodedInputStreamTest.java
new file mode 100644
index 0000000..850b8aa
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/CodedInputStreamTest.java
@@ -0,0 +1,486 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestRecursiveMessage;
+
+import junit.framework.TestCase;
+
+import java.io.ByteArrayInputStream;
+import java.io.FilterInputStream;
+import java.io.InputStream;
+import java.io.IOException;
+
+/**
+ * Unit test for {@link CodedInputStream}.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+public class CodedInputStreamTest extends TestCase {
+  /**
+   * Helper to construct a byte array from a bunch of bytes.  The inputs are
+   * actually ints so that I can use hex notation and not get stupid errors
+   * about precision.
+   */
+  private byte[] bytes(int... bytesAsInts) {
+    byte[] bytes = new byte[bytesAsInts.length];
+    for (int i = 0; i < bytesAsInts.length; i++) {
+      bytes[i] = (byte) bytesAsInts[i];
+    }
+    return bytes;
+  }
+
+  /**
+   * An InputStream which limits the number of bytes it reads at a time.
+   * We use this to make sure that CodedInputStream doesn't screw up when
+   * reading in small blocks.
+   */
+  private static final class SmallBlockInputStream extends FilterInputStream {
+    private final int blockSize;
+
+    public SmallBlockInputStream(byte[] data, int blockSize) {
+      this(new ByteArrayInputStream(data), blockSize);
+    }
+
+    public SmallBlockInputStream(InputStream in, int blockSize) {
+      super(in);
+      this.blockSize = blockSize;
+    }
+
+    public int read(byte[] b) throws IOException {
+      return super.read(b, 0, Math.min(b.length, blockSize));
+    }
+
+    public int read(byte[] b, int off, int len) throws IOException {
+      return super.read(b, off, Math.min(len, blockSize));
+    }
+  }
+
+  /**
+   * Parses the given bytes using readRawVarint32() and readRawVarint64() and
+   * checks that the result matches the given value.
+   */
+  private void assertReadVarint(byte[] data, long value) throws Exception {
+    CodedInputStream input = CodedInputStream.newInstance(data);
+    assertEquals((int)value, input.readRawVarint32());
+
+    input = CodedInputStream.newInstance(data);
+    assertEquals(value, input.readRawVarint64());
+    assertTrue(input.isAtEnd());
+
+    // Try different block sizes.
+    for (int blockSize = 1; blockSize <= 16; blockSize *= 2) {
+      input = CodedInputStream.newInstance(
+        new SmallBlockInputStream(data, blockSize));
+      assertEquals((int)value, input.readRawVarint32());
+
+      input = CodedInputStream.newInstance(
+        new SmallBlockInputStream(data, blockSize));
+      assertEquals(value, input.readRawVarint64());
+      assertTrue(input.isAtEnd());
+    }
+
+    // Try reading direct from an InputStream.  We want to verify that it
+    // doesn't read past the end of the input, so we copy to a new, bigger
+    // array first.
+    byte[] longerData = new byte[data.length + 1];
+    System.arraycopy(data, 0, longerData, 0, data.length);
+    InputStream rawInput = new ByteArrayInputStream(longerData);
+    assertEquals((int)value, CodedInputStream.readRawVarint32(rawInput));
+    assertEquals(1, rawInput.available());
+  }
+
+  /**
+   * Parses the given bytes using readRawVarint32() and readRawVarint64() and
+   * expects them to fail with an InvalidProtocolBufferException whose
+   * description matches the given one.
+   */
+  private void assertReadVarintFailure(
+      InvalidProtocolBufferException expected, byte[] data)
+      throws Exception {
+    CodedInputStream input = CodedInputStream.newInstance(data);
+    try {
+      input.readRawVarint32();
+      fail("Should have thrown an exception.");
+    } catch (InvalidProtocolBufferException e) {
+      assertEquals(expected.getMessage(), e.getMessage());
+    }
+
+    input = CodedInputStream.newInstance(data);
+    try {
+      input.readRawVarint64();
+      fail("Should have thrown an exception.");
+    } catch (InvalidProtocolBufferException e) {
+      assertEquals(expected.getMessage(), e.getMessage());
+    }
+
+    // Make sure we get the same error when reading direct from an InputStream.
+    try {
+      CodedInputStream.readRawVarint32(new ByteArrayInputStream(data));
+      fail("Should have thrown an exception.");
+    } catch (InvalidProtocolBufferException e) {
+      assertEquals(expected.getMessage(), e.getMessage());
+    }
+  }
+
+  /** Tests readRawVarint32() and readRawVarint64(). */
+  public void testReadVarint() throws Exception {
+    assertReadVarint(bytes(0x00), 0);
+    assertReadVarint(bytes(0x01), 1);
+    assertReadVarint(bytes(0x7f), 127);
+    // 14882
+    assertReadVarint(bytes(0xa2, 0x74), (0x22 << 0) | (0x74 << 7));
+    // 2961488830
+    assertReadVarint(bytes(0xbe, 0xf7, 0x92, 0x84, 0x0b),
+      (0x3e << 0) | (0x77 << 7) | (0x12 << 14) | (0x04 << 21) |
+      (0x0bL << 28));
+
+    // 64-bit
+    // 7256456126
+    assertReadVarint(bytes(0xbe, 0xf7, 0x92, 0x84, 0x1b),
+      (0x3e << 0) | (0x77 << 7) | (0x12 << 14) | (0x04 << 21) |
+      (0x1bL << 28));
+    // 41256202580718336
+    assertReadVarint(
+      bytes(0x80, 0xe6, 0xeb, 0x9c, 0xc3, 0xc9, 0xa4, 0x49),
+      (0x00 << 0) | (0x66 << 7) | (0x6b << 14) | (0x1c << 21) |
+      (0x43L << 28) | (0x49L << 35) | (0x24L << 42) | (0x49L << 49));
+    // 11964378330978735131
+    assertReadVarint(
+      bytes(0x9b, 0xa8, 0xf9, 0xc2, 0xbb, 0xd6, 0x80, 0x85, 0xa6, 0x01),
+      (0x1b << 0) | (0x28 << 7) | (0x79 << 14) | (0x42 << 21) |
+      (0x3bL << 28) | (0x56L << 35) | (0x00L << 42) |
+      (0x05L << 49) | (0x26L << 56) | (0x01L << 63));
+
+    // Failures
+    assertReadVarintFailure(
+      InvalidProtocolBufferException.malformedVarint(),
+      bytes(0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80, 0x80,
+            0x00));
+    assertReadVarintFailure(
+      InvalidProtocolBufferException.truncatedMessage(),
+      bytes(0x80));
+  }
+
+  /**
+   * Parses the given bytes using readRawLittleEndian32() and checks
+   * that the result matches the given value.
+   */
+  private void assertReadLittleEndian32(byte[] data, int value)
+                                        throws Exception {
+    CodedInputStream input = CodedInputStream.newInstance(data);
+    assertEquals(value, input.readRawLittleEndian32());
+    assertTrue(input.isAtEnd());
+
+    // Try different block sizes.
+    for (int blockSize = 1; blockSize <= 16; blockSize *= 2) {
+      input = CodedInputStream.newInstance(
+        new SmallBlockInputStream(data, blockSize));
+      assertEquals(value, input.readRawLittleEndian32());
+      assertTrue(input.isAtEnd());
+    }
+  }
+
+  /**
+   * Parses the given bytes using readRawLittleEndian64() and checks
+   * that the result matches the given value.
+   */
+  private void assertReadLittleEndian64(byte[] data, long value)
+                                        throws Exception {
+    CodedInputStream input = CodedInputStream.newInstance(data);
+    assertEquals(value, input.readRawLittleEndian64());
+    assertTrue(input.isAtEnd());
+
+    // Try different block sizes.
+    for (int blockSize = 1; blockSize <= 16; blockSize *= 2) {
+      input = CodedInputStream.newInstance(
+        new SmallBlockInputStream(data, blockSize));
+      assertEquals(value, input.readRawLittleEndian64());
+      assertTrue(input.isAtEnd());
+    }
+  }
+
+  /** Tests readRawLittleEndian32() and readRawLittleEndian64(). */
+  public void testReadLittleEndian() throws Exception {
+    assertReadLittleEndian32(bytes(0x78, 0x56, 0x34, 0x12), 0x12345678);
+    assertReadLittleEndian32(bytes(0xf0, 0xde, 0xbc, 0x9a), 0x9abcdef0);
+
+    assertReadLittleEndian64(
+      bytes(0xf0, 0xde, 0xbc, 0x9a, 0x78, 0x56, 0x34, 0x12),
+      0x123456789abcdef0L);
+    assertReadLittleEndian64(
+      bytes(0x78, 0x56, 0x34, 0x12, 0xf0, 0xde, 0xbc, 0x9a),
+      0x9abcdef012345678L);
+  }
+
+  /** Test decodeZigZag32() and decodeZigZag64(). */
+  public void testDecodeZigZag() throws Exception {
+    assertEquals( 0, CodedInputStream.decodeZigZag32(0));
+    assertEquals(-1, CodedInputStream.decodeZigZag32(1));
+    assertEquals( 1, CodedInputStream.decodeZigZag32(2));
+    assertEquals(-2, CodedInputStream.decodeZigZag32(3));
+    assertEquals(0x3FFFFFFF, CodedInputStream.decodeZigZag32(0x7FFFFFFE));
+    assertEquals(0xC0000000, CodedInputStream.decodeZigZag32(0x7FFFFFFF));
+    assertEquals(0x7FFFFFFF, CodedInputStream.decodeZigZag32(0xFFFFFFFE));
+    assertEquals(0x80000000, CodedInputStream.decodeZigZag32(0xFFFFFFFF));
+
+    assertEquals( 0, CodedInputStream.decodeZigZag64(0));
+    assertEquals(-1, CodedInputStream.decodeZigZag64(1));
+    assertEquals( 1, CodedInputStream.decodeZigZag64(2));
+    assertEquals(-2, CodedInputStream.decodeZigZag64(3));
+    assertEquals(0x000000003FFFFFFFL,
+                 CodedInputStream.decodeZigZag64(0x000000007FFFFFFEL));
+    assertEquals(0xFFFFFFFFC0000000L,
+                 CodedInputStream.decodeZigZag64(0x000000007FFFFFFFL));
+    assertEquals(0x000000007FFFFFFFL,
+                 CodedInputStream.decodeZigZag64(0x00000000FFFFFFFEL));
+    assertEquals(0xFFFFFFFF80000000L,
+                 CodedInputStream.decodeZigZag64(0x00000000FFFFFFFFL));
+    assertEquals(0x7FFFFFFFFFFFFFFFL,
+                 CodedInputStream.decodeZigZag64(0xFFFFFFFFFFFFFFFEL));
+    assertEquals(0x8000000000000000L,
+                 CodedInputStream.decodeZigZag64(0xFFFFFFFFFFFFFFFFL));
+  }
+
+  /** Tests reading and parsing a whole message with every field type. */
+  public void testReadWholeMessage() throws Exception {
+    TestAllTypes message = TestUtil.getAllSet();
+
+    byte[] rawBytes = message.toByteArray();
+    assertEquals(rawBytes.length, message.getSerializedSize());
+
+    TestAllTypes message2 = TestAllTypes.parseFrom(rawBytes);
+    TestUtil.assertAllFieldsSet(message2);
+
+    // Try different block sizes.
+    for (int blockSize = 1; blockSize < 256; blockSize *= 2) {
+      message2 = TestAllTypes.parseFrom(
+        new SmallBlockInputStream(rawBytes, blockSize));
+      TestUtil.assertAllFieldsSet(message2);
+    }
+  }
+
+  /** Tests skipField(). */
+  public void testSkipWholeMessage() throws Exception {
+    TestAllTypes message = TestUtil.getAllSet();
+    byte[] rawBytes = message.toByteArray();
+
+    // Create two parallel inputs.  Parse one as unknown fields while using
+    // skipField() to skip each field on the other.  Expect the same tags.
+    CodedInputStream input1 = CodedInputStream.newInstance(rawBytes);
+    CodedInputStream input2 = CodedInputStream.newInstance(rawBytes);
+    UnknownFieldSet.Builder unknownFields = UnknownFieldSet.newBuilder();
+
+    while (true) {
+      int tag = input1.readTag();
+      assertEquals(tag, input2.readTag());
+      if (tag == 0) {
+        break;
+      }
+      unknownFields.mergeFieldFrom(tag, input1);
+      input2.skipField(tag);
+    }
+  }
+
+  /**
+   * Test that a bug in skipRawBytes() has been fixed:  if the skip skips
+   * exactly up to a limit, this should not break things.
+   */
+  public void testSkipRawBytesBug() throws Exception {
+    byte[] rawBytes = new byte[] { 1, 2 };
+    CodedInputStream input = CodedInputStream.newInstance(rawBytes);
+
+    int limit = input.pushLimit(1);
+    input.skipRawBytes(1);
+    input.popLimit(limit);
+    assertEquals(2, input.readRawByte());
+  }
+
+  public void testReadHugeBlob() throws Exception {
+    // Allocate and initialize a 1MB blob.
+    byte[] blob = new byte[1 << 20];
+    for (int i = 0; i < blob.length; i++) {
+      blob[i] = (byte)i;
+    }
+
+    // Make a message containing it.
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TestUtil.setAllFields(builder);
+    builder.setOptionalBytes(ByteString.copyFrom(blob));
+    TestAllTypes message = builder.build();
+
+    // Serialize and parse it.  Make sure to parse from an InputStream, not
+    // directly from a ByteString, so that CodedInputStream uses buffered
+    // reading.
+    TestAllTypes message2 =
+      TestAllTypes.parseFrom(message.toByteString().newInput());
+
+    assertEquals(message.getOptionalBytes(), message2.getOptionalBytes());
+
+    // Make sure all the other fields were parsed correctly.
+    TestAllTypes message3 = TestAllTypes.newBuilder(message2)
+      .setOptionalBytes(TestUtil.getAllSet().getOptionalBytes())
+      .build();
+    TestUtil.assertAllFieldsSet(message3);
+  }
+
+  public void testReadMaliciouslyLargeBlob() throws Exception {
+    ByteString.Output rawOutput = ByteString.newOutput();
+    CodedOutputStream output = CodedOutputStream.newInstance(rawOutput);
+
+    int tag = WireFormat.makeTag(1, WireFormat.WIRETYPE_LENGTH_DELIMITED);
+    output.writeRawVarint32(tag);
+    output.writeRawVarint32(0x7FFFFFFF);
+    output.writeRawBytes(new byte[32]);  // Pad with a few random bytes.
+    output.flush();
+
+    CodedInputStream input = rawOutput.toByteString().newCodedInput();
+    assertEquals(tag, input.readTag());
+
+    try {
+      input.readBytes();
+      fail("Should have thrown an exception!");
+    } catch (InvalidProtocolBufferException e) {
+      // success.
+    }
+  }
+
+  private TestRecursiveMessage makeRecursiveMessage(int depth) {
+    if (depth == 0) {
+      return TestRecursiveMessage.newBuilder().setI(5).build();
+    } else {
+      return TestRecursiveMessage.newBuilder()
+        .setA(makeRecursiveMessage(depth - 1)).build();
+    }
+  }
+
+  private void assertMessageDepth(TestRecursiveMessage message, int depth) {
+    if (depth == 0) {
+      assertFalse(message.hasA());
+      assertEquals(5, message.getI());
+    } else {
+      assertTrue(message.hasA());
+      assertMessageDepth(message.getA(), depth - 1);
+    }
+  }
+
+  public void testMaliciousRecursion() throws Exception {
+    ByteString data64 = makeRecursiveMessage(64).toByteString();
+    ByteString data65 = makeRecursiveMessage(65).toByteString();
+
+    assertMessageDepth(TestRecursiveMessage.parseFrom(data64), 64);
+
+    try {
+      TestRecursiveMessage.parseFrom(data65);
+      fail("Should have thrown an exception!");
+    } catch (InvalidProtocolBufferException e) {
+      // success.
+    }
+
+    CodedInputStream input = data64.newCodedInput();
+    input.setRecursionLimit(8);
+    try {
+      TestRecursiveMessage.parseFrom(input);
+      fail("Should have thrown an exception!");
+    } catch (InvalidProtocolBufferException e) {
+      // success.
+    }
+  }
+
+  public void testSizeLimit() throws Exception {
+    CodedInputStream input = CodedInputStream.newInstance(
+      TestUtil.getAllSet().toByteString().newInput());
+    input.setSizeLimit(16);
+
+    try {
+      TestAllTypes.parseFrom(input);
+      fail("Should have thrown an exception!");
+    } catch (InvalidProtocolBufferException e) {
+      // success.
+    }
+  }
+
+  public void testResetSizeCounter() throws Exception {
+    CodedInputStream input = CodedInputStream.newInstance(
+        new SmallBlockInputStream(new byte[256], 8));
+    input.setSizeLimit(16);
+    input.readRawBytes(16);
+
+    try {
+      input.readRawByte();
+      fail("Should have thrown an exception!");
+    } catch (InvalidProtocolBufferException e) {
+      // success.
+    }
+
+    input.resetSizeCounter();
+    input.readRawByte();  // No exception thrown.
+
+    try {
+      input.readRawBytes(16);  // Hits limit again.
+      fail("Should have thrown an exception!");
+    } catch (InvalidProtocolBufferException e) {
+      // success.
+    }
+  }
+
+  /**
+   * Tests that if we read an string that contains invalid UTF-8, no exception
+   * is thrown.  Instead, the invalid bytes are replaced with the Unicode
+   * "replacement character" U+FFFD.
+   */
+  public void testReadInvalidUtf8() throws Exception {
+    ByteString.Output rawOutput = ByteString.newOutput();
+    CodedOutputStream output = CodedOutputStream.newInstance(rawOutput);
+
+    int tag = WireFormat.makeTag(1, WireFormat.WIRETYPE_LENGTH_DELIMITED);
+    output.writeRawVarint32(tag);
+    output.writeRawVarint32(1);
+    output.writeRawBytes(new byte[] { (byte)0x80 });
+    output.flush();
+
+    CodedInputStream input = rawOutput.toByteString().newCodedInput();
+    assertEquals(tag, input.readTag());
+    String text = input.readString();
+    assertEquals(0xfffd, text.charAt(0));
+  }
+
+  public void testReadFromSlice() throws Exception {
+    byte[] bytes = bytes(0, 1, 2, 3, 4, 5, 6, 7, 8, 9);
+    CodedInputStream in = CodedInputStream.newInstance(bytes, 3, 5);
+    for (int i = 3; i < 8; i++) {
+      assertEquals(i, in.readRawByte());
+    }
+    // eof
+    assertEquals(0, in.readTag());
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/CodedOutputStreamTest.java b/java/src/test/java/com/google/protobuf/CodedOutputStreamTest.java
new file mode 100644
index 0000000..c42b485
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/CodedOutputStreamTest.java
@@ -0,0 +1,304 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestPackedTypes;
+
+import junit.framework.TestCase;
+
+import java.io.ByteArrayOutputStream;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Unit test for {@link CodedOutputStream}.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+public class CodedOutputStreamTest extends TestCase {
+  /**
+   * Helper to construct a byte array from a bunch of bytes.  The inputs are
+   * actually ints so that I can use hex notation and not get stupid errors
+   * about precision.
+   */
+  private byte[] bytes(int... bytesAsInts) {
+    byte[] bytes = new byte[bytesAsInts.length];
+    for (int i = 0; i < bytesAsInts.length; i++) {
+      bytes[i] = (byte) bytesAsInts[i];
+    }
+    return bytes;
+  }
+
+  /** Arrays.asList() does not work with arrays of primitives.  :( */
+  private List<Byte> toList(byte[] bytes) {
+    List<Byte> result = new ArrayList<Byte>();
+    for (byte b : bytes) {
+      result.add(b);
+    }
+    return result;
+  }
+
+  private void assertEqualBytes(byte[] a, byte[] b) {
+    assertEquals(toList(a), toList(b));
+  }
+
+  /**
+   * Writes the given value using writeRawVarint32() and writeRawVarint64() and
+   * checks that the result matches the given bytes.
+   */
+  private void assertWriteVarint(byte[] data, long value) throws Exception {
+    // Only do 32-bit write if the value fits in 32 bits.
+    if ((value >>> 32) == 0) {
+      ByteArrayOutputStream rawOutput = new ByteArrayOutputStream();
+      CodedOutputStream output = CodedOutputStream.newInstance(rawOutput);
+      output.writeRawVarint32((int) value);
+      output.flush();
+      assertEqualBytes(data, rawOutput.toByteArray());
+
+      // Also try computing size.
+      assertEquals(data.length,
+                   CodedOutputStream.computeRawVarint32Size((int) value));
+    }
+
+    {
+      ByteArrayOutputStream rawOutput = new ByteArrayOutputStream();
+      CodedOutputStream output = CodedOutputStream.newInstance(rawOutput);
+      output.writeRawVarint64(value);
+      output.flush();
+      assertEqualBytes(data, rawOutput.toByteArray());
+
+      // Also try computing size.
+      assertEquals(data.length,
+                   CodedOutputStream.computeRawVarint64Size(value));
+    }
+
+    // Try different block sizes.
+    for (int blockSize = 1; blockSize <= 16; blockSize *= 2) {
+      // Only do 32-bit write if the value fits in 32 bits.
+      if ((value >>> 32) == 0) {
+        ByteArrayOutputStream rawOutput = new ByteArrayOutputStream();
+        CodedOutputStream output =
+          CodedOutputStream.newInstance(rawOutput, blockSize);
+        output.writeRawVarint32((int) value);
+        output.flush();
+        assertEqualBytes(data, rawOutput.toByteArray());
+      }
+
+      {
+        ByteArrayOutputStream rawOutput = new ByteArrayOutputStream();
+        CodedOutputStream output =
+          CodedOutputStream.newInstance(rawOutput, blockSize);
+        output.writeRawVarint64(value);
+        output.flush();
+        assertEqualBytes(data, rawOutput.toByteArray());
+      }
+    }
+  }
+
+  /** Tests writeRawVarint32() and writeRawVarint64(). */
+  public void testWriteVarint() throws Exception {
+    assertWriteVarint(bytes(0x00), 0);
+    assertWriteVarint(bytes(0x01), 1);
+    assertWriteVarint(bytes(0x7f), 127);
+    // 14882
+    assertWriteVarint(bytes(0xa2, 0x74), (0x22 << 0) | (0x74 << 7));
+    // 2961488830
+    assertWriteVarint(bytes(0xbe, 0xf7, 0x92, 0x84, 0x0b),
+      (0x3e << 0) | (0x77 << 7) | (0x12 << 14) | (0x04 << 21) |
+      (0x0bL << 28));
+
+    // 64-bit
+    // 7256456126
+    assertWriteVarint(bytes(0xbe, 0xf7, 0x92, 0x84, 0x1b),
+      (0x3e << 0) | (0x77 << 7) | (0x12 << 14) | (0x04 << 21) |
+      (0x1bL << 28));
+    // 41256202580718336
+    assertWriteVarint(
+      bytes(0x80, 0xe6, 0xeb, 0x9c, 0xc3, 0xc9, 0xa4, 0x49),
+      (0x00 << 0) | (0x66 << 7) | (0x6b << 14) | (0x1c << 21) |
+      (0x43L << 28) | (0x49L << 35) | (0x24L << 42) | (0x49L << 49));
+    // 11964378330978735131
+    assertWriteVarint(
+      bytes(0x9b, 0xa8, 0xf9, 0xc2, 0xbb, 0xd6, 0x80, 0x85, 0xa6, 0x01),
+      (0x1b << 0) | (0x28 << 7) | (0x79 << 14) | (0x42 << 21) |
+      (0x3bL << 28) | (0x56L << 35) | (0x00L << 42) |
+      (0x05L << 49) | (0x26L << 56) | (0x01L << 63));
+  }
+
+  /**
+   * Parses the given bytes using writeRawLittleEndian32() and checks
+   * that the result matches the given value.
+   */
+  private void assertWriteLittleEndian32(byte[] data, int value)
+                                         throws Exception {
+    ByteArrayOutputStream rawOutput = new ByteArrayOutputStream();
+    CodedOutputStream output = CodedOutputStream.newInstance(rawOutput);
+    output.writeRawLittleEndian32(value);
+    output.flush();
+    assertEqualBytes(data, rawOutput.toByteArray());
+
+    // Try different block sizes.
+    for (int blockSize = 1; blockSize <= 16; blockSize *= 2) {
+      rawOutput = new ByteArrayOutputStream();
+      output = CodedOutputStream.newInstance(rawOutput, blockSize);
+      output.writeRawLittleEndian32(value);
+      output.flush();
+      assertEqualBytes(data, rawOutput.toByteArray());
+    }
+  }
+
+  /**
+   * Parses the given bytes using writeRawLittleEndian64() and checks
+   * that the result matches the given value.
+   */
+  private void assertWriteLittleEndian64(byte[] data, long value)
+                                         throws Exception {
+    ByteArrayOutputStream rawOutput = new ByteArrayOutputStream();
+    CodedOutputStream output = CodedOutputStream.newInstance(rawOutput);
+    output.writeRawLittleEndian64(value);
+    output.flush();
+    assertEqualBytes(data, rawOutput.toByteArray());
+
+    // Try different block sizes.
+    for (int blockSize = 1; blockSize <= 16; blockSize *= 2) {
+      rawOutput = new ByteArrayOutputStream();
+      output = CodedOutputStream.newInstance(rawOutput, blockSize);
+      output.writeRawLittleEndian64(value);
+      output.flush();
+      assertEqualBytes(data, rawOutput.toByteArray());
+    }
+  }
+
+  /** Tests writeRawLittleEndian32() and writeRawLittleEndian64(). */
+  public void testWriteLittleEndian() throws Exception {
+    assertWriteLittleEndian32(bytes(0x78, 0x56, 0x34, 0x12), 0x12345678);
+    assertWriteLittleEndian32(bytes(0xf0, 0xde, 0xbc, 0x9a), 0x9abcdef0);
+
+    assertWriteLittleEndian64(
+      bytes(0xf0, 0xde, 0xbc, 0x9a, 0x78, 0x56, 0x34, 0x12),
+      0x123456789abcdef0L);
+    assertWriteLittleEndian64(
+      bytes(0x78, 0x56, 0x34, 0x12, 0xf0, 0xde, 0xbc, 0x9a),
+      0x9abcdef012345678L);
+  }
+
+  /** Test encodeZigZag32() and encodeZigZag64(). */
+  public void testEncodeZigZag() throws Exception {
+    assertEquals(0, CodedOutputStream.encodeZigZag32( 0));
+    assertEquals(1, CodedOutputStream.encodeZigZag32(-1));
+    assertEquals(2, CodedOutputStream.encodeZigZag32( 1));
+    assertEquals(3, CodedOutputStream.encodeZigZag32(-2));
+    assertEquals(0x7FFFFFFE, CodedOutputStream.encodeZigZag32(0x3FFFFFFF));
+    assertEquals(0x7FFFFFFF, CodedOutputStream.encodeZigZag32(0xC0000000));
+    assertEquals(0xFFFFFFFE, CodedOutputStream.encodeZigZag32(0x7FFFFFFF));
+    assertEquals(0xFFFFFFFF, CodedOutputStream.encodeZigZag32(0x80000000));
+
+    assertEquals(0, CodedOutputStream.encodeZigZag64( 0));
+    assertEquals(1, CodedOutputStream.encodeZigZag64(-1));
+    assertEquals(2, CodedOutputStream.encodeZigZag64( 1));
+    assertEquals(3, CodedOutputStream.encodeZigZag64(-2));
+    assertEquals(0x000000007FFFFFFEL,
+                 CodedOutputStream.encodeZigZag64(0x000000003FFFFFFFL));
+    assertEquals(0x000000007FFFFFFFL,
+                 CodedOutputStream.encodeZigZag64(0xFFFFFFFFC0000000L));
+    assertEquals(0x00000000FFFFFFFEL,
+                 CodedOutputStream.encodeZigZag64(0x000000007FFFFFFFL));
+    assertEquals(0x00000000FFFFFFFFL,
+                 CodedOutputStream.encodeZigZag64(0xFFFFFFFF80000000L));
+    assertEquals(0xFFFFFFFFFFFFFFFEL,
+                 CodedOutputStream.encodeZigZag64(0x7FFFFFFFFFFFFFFFL));
+    assertEquals(0xFFFFFFFFFFFFFFFFL,
+                 CodedOutputStream.encodeZigZag64(0x8000000000000000L));
+
+    // Some easier-to-verify round-trip tests.  The inputs (other than 0, 1, -1)
+    // were chosen semi-randomly via keyboard bashing.
+    assertEquals(0,
+      CodedOutputStream.encodeZigZag32(CodedInputStream.decodeZigZag32(0)));
+    assertEquals(1,
+      CodedOutputStream.encodeZigZag32(CodedInputStream.decodeZigZag32(1)));
+    assertEquals(-1,
+      CodedOutputStream.encodeZigZag32(CodedInputStream.decodeZigZag32(-1)));
+    assertEquals(14927,
+      CodedOutputStream.encodeZigZag32(CodedInputStream.decodeZigZag32(14927)));
+    assertEquals(-3612,
+      CodedOutputStream.encodeZigZag32(CodedInputStream.decodeZigZag32(-3612)));
+
+    assertEquals(0,
+      CodedOutputStream.encodeZigZag64(CodedInputStream.decodeZigZag64(0)));
+    assertEquals(1,
+      CodedOutputStream.encodeZigZag64(CodedInputStream.decodeZigZag64(1)));
+    assertEquals(-1,
+      CodedOutputStream.encodeZigZag64(CodedInputStream.decodeZigZag64(-1)));
+    assertEquals(14927,
+      CodedOutputStream.encodeZigZag64(CodedInputStream.decodeZigZag64(14927)));
+    assertEquals(-3612,
+      CodedOutputStream.encodeZigZag64(CodedInputStream.decodeZigZag64(-3612)));
+
+    assertEquals(856912304801416L,
+      CodedOutputStream.encodeZigZag64(
+        CodedInputStream.decodeZigZag64(
+          856912304801416L)));
+    assertEquals(-75123905439571256L,
+      CodedOutputStream.encodeZigZag64(
+        CodedInputStream.decodeZigZag64(
+          -75123905439571256L)));
+  }
+
+  /** Tests writing a whole message with every field type. */
+  public void testWriteWholeMessage() throws Exception {
+    TestAllTypes message = TestUtil.getAllSet();
+
+    byte[] rawBytes = message.toByteArray();
+    assertEqualBytes(TestUtil.getGoldenMessage().toByteArray(), rawBytes);
+
+    // Try different block sizes.
+    for (int blockSize = 1; blockSize < 256; blockSize *= 2) {
+      ByteArrayOutputStream rawOutput = new ByteArrayOutputStream();
+      CodedOutputStream output =
+        CodedOutputStream.newInstance(rawOutput, blockSize);
+      message.writeTo(output);
+      output.flush();
+      assertEqualBytes(rawBytes, rawOutput.toByteArray());
+    }
+  }
+
+  /** Tests writing a whole message with every packed field type. Ensures the
+   * wire format of packed fields is compatible with C++. */
+  public void testWriteWholePackedFieldsMessage() throws Exception {
+    TestPackedTypes message = TestUtil.getPackedSet();
+
+    byte[] rawBytes = message.toByteArray();
+    assertEqualBytes(TestUtil.getGoldenPackedFieldsMessage().toByteArray(),
+                     rawBytes);
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/DescriptorsTest.java b/java/src/test/java/com/google/protobuf/DescriptorsTest.java
new file mode 100644
index 0000000..c5c38b2
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/DescriptorsTest.java
@@ -0,0 +1,408 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import com.google.protobuf.Descriptors.FileDescriptor;
+import com.google.protobuf.Descriptors.Descriptor;
+import com.google.protobuf.Descriptors.FieldDescriptor;
+import com.google.protobuf.Descriptors.EnumDescriptor;
+import com.google.protobuf.Descriptors.EnumValueDescriptor;
+import com.google.protobuf.Descriptors.ServiceDescriptor;
+import com.google.protobuf.Descriptors.MethodDescriptor;
+
+import com.google.protobuf.test.UnittestImport;
+import com.google.protobuf.test.UnittestImport.ImportEnum;
+import com.google.protobuf.test.UnittestImport.ImportMessage;
+import protobuf_unittest.UnittestProto;
+import protobuf_unittest.UnittestProto.ForeignEnum;
+import protobuf_unittest.UnittestProto.ForeignMessage;
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestAllExtensions;
+import protobuf_unittest.UnittestProto.TestExtremeDefaultValues;
+import protobuf_unittest.UnittestProto.TestRequired;
+import protobuf_unittest.UnittestProto.TestService;
+import protobuf_unittest.UnittestCustomOptions;
+
+
+import junit.framework.TestCase;
+
+import java.util.Arrays;
+import java.util.Collections;
+
+/**
+ * Unit test for {@link Descriptors}.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+public class DescriptorsTest extends TestCase {
+  public void testFileDescriptor() throws Exception {
+    FileDescriptor file = UnittestProto.getDescriptor();
+
+    assertEquals("google/protobuf/unittest.proto", file.getName());
+    assertEquals("protobuf_unittest", file.getPackage());
+
+    assertEquals("UnittestProto", file.getOptions().getJavaOuterClassname());
+    assertEquals("google/protobuf/unittest.proto",
+                 file.toProto().getName());
+
+    assertEquals(Arrays.asList(UnittestImport.getDescriptor()),
+                 file.getDependencies());
+
+    Descriptor messageType = TestAllTypes.getDescriptor();
+    assertEquals(messageType, file.getMessageTypes().get(0));
+    assertEquals(messageType, file.findMessageTypeByName("TestAllTypes"));
+    assertNull(file.findMessageTypeByName("NoSuchType"));
+    assertNull(file.findMessageTypeByName("protobuf_unittest.TestAllTypes"));
+    for (int i = 0; i < file.getMessageTypes().size(); i++) {
+      assertEquals(i, file.getMessageTypes().get(i).getIndex());
+    }
+
+    EnumDescriptor enumType = ForeignEnum.getDescriptor();
+    assertEquals(enumType, file.getEnumTypes().get(0));
+    assertEquals(enumType, file.findEnumTypeByName("ForeignEnum"));
+    assertNull(file.findEnumTypeByName("NoSuchType"));
+    assertNull(file.findEnumTypeByName("protobuf_unittest.ForeignEnum"));
+    assertEquals(Arrays.asList(ImportEnum.getDescriptor()),
+                 UnittestImport.getDescriptor().getEnumTypes());
+    for (int i = 0; i < file.getEnumTypes().size(); i++) {
+      assertEquals(i, file.getEnumTypes().get(i).getIndex());
+    }
+
+    ServiceDescriptor service = TestService.getDescriptor();
+    assertEquals(service, file.getServices().get(0));
+    assertEquals(service, file.findServiceByName("TestService"));
+    assertNull(file.findServiceByName("NoSuchType"));
+    assertNull(file.findServiceByName("protobuf_unittest.TestService"));
+    assertEquals(Collections.emptyList(),
+                 UnittestImport.getDescriptor().getServices());
+    for (int i = 0; i < file.getServices().size(); i++) {
+      assertEquals(i, file.getServices().get(i).getIndex());
+    }
+
+    FieldDescriptor extension =
+      UnittestProto.optionalInt32Extension.getDescriptor();
+    assertEquals(extension, file.getExtensions().get(0));
+    assertEquals(extension,
+                 file.findExtensionByName("optional_int32_extension"));
+    assertNull(file.findExtensionByName("no_such_ext"));
+    assertNull(file.findExtensionByName(
+      "protobuf_unittest.optional_int32_extension"));
+    assertEquals(Collections.emptyList(),
+                 UnittestImport.getDescriptor().getExtensions());
+    for (int i = 0; i < file.getExtensions().size(); i++) {
+      assertEquals(i, file.getExtensions().get(i).getIndex());
+    }
+  }
+
+  public void testDescriptor() throws Exception {
+    Descriptor messageType = TestAllTypes.getDescriptor();
+    Descriptor nestedType = TestAllTypes.NestedMessage.getDescriptor();
+
+    assertEquals("TestAllTypes", messageType.getName());
+    assertEquals("protobuf_unittest.TestAllTypes", messageType.getFullName());
+    assertEquals(UnittestProto.getDescriptor(), messageType.getFile());
+    assertNull(messageType.getContainingType());
+    assertEquals(DescriptorProtos.MessageOptions.getDefaultInstance(),
+                 messageType.getOptions());
+    assertEquals("TestAllTypes", messageType.toProto().getName());
+
+    assertEquals("NestedMessage", nestedType.getName());
+    assertEquals("protobuf_unittest.TestAllTypes.NestedMessage",
+                 nestedType.getFullName());
+    assertEquals(UnittestProto.getDescriptor(), nestedType.getFile());
+    assertEquals(messageType, nestedType.getContainingType());
+
+    FieldDescriptor field = messageType.getFields().get(0);
+    assertEquals("optional_int32", field.getName());
+    assertEquals(field, messageType.findFieldByName("optional_int32"));
+    assertNull(messageType.findFieldByName("no_such_field"));
+    assertEquals(field, messageType.findFieldByNumber(1));
+    assertNull(messageType.findFieldByNumber(571283));
+    for (int i = 0; i < messageType.getFields().size(); i++) {
+      assertEquals(i, messageType.getFields().get(i).getIndex());
+    }
+
+    assertEquals(nestedType, messageType.getNestedTypes().get(0));
+    assertEquals(nestedType, messageType.findNestedTypeByName("NestedMessage"));
+    assertNull(messageType.findNestedTypeByName("NoSuchType"));
+    for (int i = 0; i < messageType.getNestedTypes().size(); i++) {
+      assertEquals(i, messageType.getNestedTypes().get(i).getIndex());
+    }
+
+    EnumDescriptor enumType = TestAllTypes.NestedEnum.getDescriptor();
+    assertEquals(enumType, messageType.getEnumTypes().get(0));
+    assertEquals(enumType, messageType.findEnumTypeByName("NestedEnum"));
+    assertNull(messageType.findEnumTypeByName("NoSuchType"));
+    for (int i = 0; i < messageType.getEnumTypes().size(); i++) {
+      assertEquals(i, messageType.getEnumTypes().get(i).getIndex());
+    }
+  }
+
+  public void testFieldDescriptor() throws Exception {
+    Descriptor messageType = TestAllTypes.getDescriptor();
+    FieldDescriptor primitiveField =
+      messageType.findFieldByName("optional_int32");
+    FieldDescriptor enumField =
+      messageType.findFieldByName("optional_nested_enum");
+    FieldDescriptor messageField =
+      messageType.findFieldByName("optional_foreign_message");
+    FieldDescriptor cordField =
+      messageType.findFieldByName("optional_cord");
+    FieldDescriptor extension =
+      UnittestProto.optionalInt32Extension.getDescriptor();
+    FieldDescriptor nestedExtension = TestRequired.single.getDescriptor();
+
+    assertEquals("optional_int32", primitiveField.getName());
+    assertEquals("protobuf_unittest.TestAllTypes.optional_int32",
+                 primitiveField.getFullName());
+    assertEquals(1, primitiveField.getNumber());
+    assertEquals(messageType, primitiveField.getContainingType());
+    assertEquals(UnittestProto.getDescriptor(), primitiveField.getFile());
+    assertEquals(FieldDescriptor.Type.INT32, primitiveField.getType());
+    assertEquals(FieldDescriptor.JavaType.INT, primitiveField.getJavaType());
+    assertEquals(DescriptorProtos.FieldOptions.getDefaultInstance(),
+                 primitiveField.getOptions());
+    assertFalse(primitiveField.isExtension());
+    assertEquals("optional_int32", primitiveField.toProto().getName());
+
+    assertEquals("optional_nested_enum", enumField.getName());
+    assertEquals(FieldDescriptor.Type.ENUM, enumField.getType());
+    assertEquals(FieldDescriptor.JavaType.ENUM, enumField.getJavaType());
+    assertEquals(TestAllTypes.NestedEnum.getDescriptor(),
+                 enumField.getEnumType());
+
+    assertEquals("optional_foreign_message", messageField.getName());
+    assertEquals(FieldDescriptor.Type.MESSAGE, messageField.getType());
+    assertEquals(FieldDescriptor.JavaType.MESSAGE, messageField.getJavaType());
+    assertEquals(ForeignMessage.getDescriptor(), messageField.getMessageType());
+
+    assertEquals("optional_cord", cordField.getName());
+    assertEquals(FieldDescriptor.Type.STRING, cordField.getType());
+    assertEquals(FieldDescriptor.JavaType.STRING, cordField.getJavaType());
+    assertEquals(DescriptorProtos.FieldOptions.CType.CORD,
+                 cordField.getOptions().getCtype());
+
+    assertEquals("optional_int32_extension", extension.getName());
+    assertEquals("protobuf_unittest.optional_int32_extension",
+                 extension.getFullName());
+    assertEquals(1, extension.getNumber());
+    assertEquals(TestAllExtensions.getDescriptor(),
+                 extension.getContainingType());
+    assertEquals(UnittestProto.getDescriptor(), extension.getFile());
+    assertEquals(FieldDescriptor.Type.INT32, extension.getType());
+    assertEquals(FieldDescriptor.JavaType.INT, extension.getJavaType());
+    assertEquals(DescriptorProtos.FieldOptions.getDefaultInstance(),
+                 extension.getOptions());
+    assertTrue(extension.isExtension());
+    assertEquals(null, extension.getExtensionScope());
+    assertEquals("optional_int32_extension", extension.toProto().getName());
+
+    assertEquals("single", nestedExtension.getName());
+    assertEquals("protobuf_unittest.TestRequired.single",
+                 nestedExtension.getFullName());
+    assertEquals(TestRequired.getDescriptor(),
+                 nestedExtension.getExtensionScope());
+  }
+
+  public void testFieldDescriptorLabel() throws Exception {
+    FieldDescriptor requiredField =
+      TestRequired.getDescriptor().findFieldByName("a");
+    FieldDescriptor optionalField =
+      TestAllTypes.getDescriptor().findFieldByName("optional_int32");
+    FieldDescriptor repeatedField =
+      TestAllTypes.getDescriptor().findFieldByName("repeated_int32");
+
+    assertTrue(requiredField.isRequired());
+    assertFalse(requiredField.isRepeated());
+    assertFalse(optionalField.isRequired());
+    assertFalse(optionalField.isRepeated());
+    assertFalse(repeatedField.isRequired());
+    assertTrue(repeatedField.isRepeated());
+  }
+
+  public void testFieldDescriptorDefault() throws Exception {
+    Descriptor d = TestAllTypes.getDescriptor();
+    assertFalse(d.findFieldByName("optional_int32").hasDefaultValue());
+    assertEquals(0, d.findFieldByName("optional_int32").getDefaultValue());
+    assertTrue(d.findFieldByName("default_int32").hasDefaultValue());
+    assertEquals(41, d.findFieldByName("default_int32").getDefaultValue());
+
+    d = TestExtremeDefaultValues.getDescriptor();
+    assertEquals(
+      ByteString.copyFrom(
+        "\0\001\007\b\f\n\r\t\013\\\'\"\u00fe".getBytes("ISO-8859-1")),
+      d.findFieldByName("escaped_bytes").getDefaultValue());
+    assertEquals(-1, d.findFieldByName("large_uint32").getDefaultValue());
+    assertEquals(-1L, d.findFieldByName("large_uint64").getDefaultValue());
+  }
+
+  public void testEnumDescriptor() throws Exception {
+    EnumDescriptor enumType = ForeignEnum.getDescriptor();
+    EnumDescriptor nestedType = TestAllTypes.NestedEnum.getDescriptor();
+
+    assertEquals("ForeignEnum", enumType.getName());
+    assertEquals("protobuf_unittest.ForeignEnum", enumType.getFullName());
+    assertEquals(UnittestProto.getDescriptor(), enumType.getFile());
+    assertNull(enumType.getContainingType());
+    assertEquals(DescriptorProtos.EnumOptions.getDefaultInstance(),
+                 enumType.getOptions());
+
+    assertEquals("NestedEnum", nestedType.getName());
+    assertEquals("protobuf_unittest.TestAllTypes.NestedEnum",
+                 nestedType.getFullName());
+    assertEquals(UnittestProto.getDescriptor(), nestedType.getFile());
+    assertEquals(TestAllTypes.getDescriptor(), nestedType.getContainingType());
+
+    EnumValueDescriptor value = ForeignEnum.FOREIGN_FOO.getValueDescriptor();
+    assertEquals(value, enumType.getValues().get(0));
+    assertEquals("FOREIGN_FOO", value.getName());
+    assertEquals(4, value.getNumber());
+    assertEquals(value, enumType.findValueByName("FOREIGN_FOO"));
+    assertEquals(value, enumType.findValueByNumber(4));
+    assertNull(enumType.findValueByName("NO_SUCH_VALUE"));
+    for (int i = 0; i < enumType.getValues().size(); i++) {
+      assertEquals(i, enumType.getValues().get(i).getIndex());
+    }
+  }
+
+  public void testServiceDescriptor() throws Exception {
+    ServiceDescriptor service = TestService.getDescriptor();
+
+    assertEquals("TestService", service.getName());
+    assertEquals("protobuf_unittest.TestService", service.getFullName());
+    assertEquals(UnittestProto.getDescriptor(), service.getFile());
+
+    assertEquals(2, service.getMethods().size());
+
+    MethodDescriptor fooMethod = service.getMethods().get(0);
+    assertEquals("Foo", fooMethod.getName());
+    assertEquals(UnittestProto.FooRequest.getDescriptor(),
+                 fooMethod.getInputType());
+    assertEquals(UnittestProto.FooResponse.getDescriptor(),
+                 fooMethod.getOutputType());
+    assertEquals(fooMethod, service.findMethodByName("Foo"));
+
+    MethodDescriptor barMethod = service.getMethods().get(1);
+    assertEquals("Bar", barMethod.getName());
+    assertEquals(UnittestProto.BarRequest.getDescriptor(),
+                 barMethod.getInputType());
+    assertEquals(UnittestProto.BarResponse.getDescriptor(),
+                 barMethod.getOutputType());
+    assertEquals(barMethod, service.findMethodByName("Bar"));
+
+    assertNull(service.findMethodByName("NoSuchMethod"));
+
+    for (int i = 0; i < service.getMethods().size(); i++) {
+      assertEquals(i, service.getMethods().get(i).getIndex());
+    }
+  }
+
+
+  public void testCustomOptions() throws Exception {
+    Descriptor descriptor =
+      UnittestCustomOptions.TestMessageWithCustomOptions.getDescriptor();
+
+    assertTrue(
+      descriptor.getOptions().hasExtension(UnittestCustomOptions.messageOpt1));
+    assertEquals(Integer.valueOf(-56),
+      descriptor.getOptions().getExtension(UnittestCustomOptions.messageOpt1));
+
+    FieldDescriptor field = descriptor.findFieldByName("field1");
+    assertNotNull(field);
+
+    assertTrue(
+      field.getOptions().hasExtension(UnittestCustomOptions.fieldOpt1));
+    assertEquals(Long.valueOf(8765432109L),
+      field.getOptions().getExtension(UnittestCustomOptions.fieldOpt1));
+
+    EnumDescriptor enumType =
+      UnittestCustomOptions.TestMessageWithCustomOptions.AnEnum.getDescriptor();
+
+    assertTrue(
+      enumType.getOptions().hasExtension(UnittestCustomOptions.enumOpt1));
+    assertEquals(Integer.valueOf(-789),
+      enumType.getOptions().getExtension(UnittestCustomOptions.enumOpt1));
+
+    ServiceDescriptor service =
+      UnittestCustomOptions.TestServiceWithCustomOptions.getDescriptor();
+
+    assertTrue(
+      service.getOptions().hasExtension(UnittestCustomOptions.serviceOpt1));
+    assertEquals(Long.valueOf(-9876543210L),
+      service.getOptions().getExtension(UnittestCustomOptions.serviceOpt1));
+
+    MethodDescriptor method = service.findMethodByName("Foo");
+    assertNotNull(method);
+
+    assertTrue(
+      method.getOptions().hasExtension(UnittestCustomOptions.methodOpt1));
+    assertEquals(UnittestCustomOptions.MethodOpt1.METHODOPT1_VAL2,
+      method.getOptions().getExtension(UnittestCustomOptions.methodOpt1));
+  }
+
+  /**
+   * Test that the FieldDescriptor.Type enum is the same as the
+   * WireFormat.FieldType enum.
+   */
+  public void testFieldTypeTablesMatch() throws Exception {
+    FieldDescriptor.Type[] values1 = FieldDescriptor.Type.values();
+    WireFormat.FieldType[] values2 = WireFormat.FieldType.values();
+
+    assertEquals(values1.length, values2.length);
+
+    for (int i = 0; i < values1.length; i++) {
+      assertEquals(values1[i].toString(), values2[i].toString());
+    }
+  }
+
+  /**
+   * Test that the FieldDescriptor.JavaType enum is the same as the
+   * WireFormat.JavaType enum.
+   */
+  public void testJavaTypeTablesMatch() throws Exception {
+    FieldDescriptor.JavaType[] values1 = FieldDescriptor.JavaType.values();
+    WireFormat.JavaType[] values2 = WireFormat.JavaType.values();
+
+    assertEquals(values1.length, values2.length);
+
+    for (int i = 0; i < values1.length; i++) {
+      assertEquals(values1[i].toString(), values2[i].toString());
+    }
+  }
+
+  public void testEnormousDescriptor() throws Exception {
+    // The descriptor for this file is larger than 64k, yet it did not cause
+    // a compiler error due to an over-long string literal.
+    assertTrue(
+        UnittestEnormousDescriptor.getDescriptor()
+          .toProto().getSerializedSize() > 65536);
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/DynamicMessageTest.java b/java/src/test/java/com/google/protobuf/DynamicMessageTest.java
new file mode 100644
index 0000000..aabccda
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/DynamicMessageTest.java
@@ -0,0 +1,226 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestAllExtensions;
+import protobuf_unittest.UnittestProto.TestPackedTypes;
+
+import junit.framework.TestCase;
+import java.util.Arrays;
+
+/**
+ * Unit test for {@link DynamicMessage}.  See also {@link MessageTest}, which
+ * tests some {@link DynamicMessage} functionality.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+public class DynamicMessageTest extends TestCase {
+  TestUtil.ReflectionTester reflectionTester =
+    new TestUtil.ReflectionTester(TestAllTypes.getDescriptor(), null);
+
+  TestUtil.ReflectionTester extensionsReflectionTester =
+    new TestUtil.ReflectionTester(TestAllExtensions.getDescriptor(),
+                                  TestUtil.getExtensionRegistry());
+  TestUtil.ReflectionTester packedReflectionTester =
+    new TestUtil.ReflectionTester(TestPackedTypes.getDescriptor(), null);
+
+  public void testDynamicMessageAccessors() throws Exception {
+    Message.Builder builder =
+      DynamicMessage.newBuilder(TestAllTypes.getDescriptor());
+    reflectionTester.setAllFieldsViaReflection(builder);
+    Message message = builder.build();
+    reflectionTester.assertAllFieldsSetViaReflection(message);
+  }
+
+  public void testDoubleBuildError() throws Exception {
+    Message.Builder builder =
+      DynamicMessage.newBuilder(TestAllTypes.getDescriptor());
+    builder.build();
+    try {
+      builder.build();
+      fail("Should have thrown exception.");
+    } catch (IllegalStateException e) {
+      // Success.
+    }
+  }
+
+  public void testClearAfterBuildError() throws Exception {
+    Message.Builder builder =
+      DynamicMessage.newBuilder(TestAllTypes.getDescriptor());
+    builder.build();
+    try {
+      builder.clear();
+      fail("Should have thrown exception.");
+    } catch (IllegalStateException e) {
+      // Success.
+    }
+  }
+
+  public void testDynamicMessageSettersRejectNull() throws Exception {
+    Message.Builder builder =
+      DynamicMessage.newBuilder(TestAllTypes.getDescriptor());
+    reflectionTester.assertReflectionSettersRejectNull(builder);
+  }
+
+  public void testDynamicMessageExtensionAccessors() throws Exception {
+    // We don't need to extensively test DynamicMessage's handling of
+    // extensions because, frankly, it doesn't do anything special with them.
+    // It treats them just like any other fields.
+    Message.Builder builder =
+      DynamicMessage.newBuilder(TestAllExtensions.getDescriptor());
+    extensionsReflectionTester.setAllFieldsViaReflection(builder);
+    Message message = builder.build();
+    extensionsReflectionTester.assertAllFieldsSetViaReflection(message);
+  }
+
+  public void testDynamicMessageExtensionSettersRejectNull() throws Exception {
+    Message.Builder builder =
+      DynamicMessage.newBuilder(TestAllExtensions.getDescriptor());
+    extensionsReflectionTester.assertReflectionSettersRejectNull(builder);
+  }
+
+  public void testDynamicMessageRepeatedSetters() throws Exception {
+    Message.Builder builder =
+      DynamicMessage.newBuilder(TestAllTypes.getDescriptor());
+    reflectionTester.setAllFieldsViaReflection(builder);
+    reflectionTester.modifyRepeatedFieldsViaReflection(builder);
+    Message message = builder.build();
+    reflectionTester.assertRepeatedFieldsModifiedViaReflection(message);
+  }
+
+  public void testDynamicMessageRepeatedSettersRejectNull() throws Exception {
+    Message.Builder builder =
+      DynamicMessage.newBuilder(TestAllTypes.getDescriptor());
+    reflectionTester.assertReflectionRepeatedSettersRejectNull(builder);
+  }
+
+  public void testDynamicMessageDefaults() throws Exception {
+    reflectionTester.assertClearViaReflection(
+      DynamicMessage.getDefaultInstance(TestAllTypes.getDescriptor()));
+    reflectionTester.assertClearViaReflection(
+      DynamicMessage.newBuilder(TestAllTypes.getDescriptor()).build());
+  }
+
+  public void testDynamicMessageSerializedSize() throws Exception {
+    TestAllTypes message = TestUtil.getAllSet();
+
+    Message.Builder dynamicBuilder =
+      DynamicMessage.newBuilder(TestAllTypes.getDescriptor());
+    reflectionTester.setAllFieldsViaReflection(dynamicBuilder);
+    Message dynamicMessage = dynamicBuilder.build();
+
+    assertEquals(message.getSerializedSize(),
+                 dynamicMessage.getSerializedSize());
+  }
+
+  public void testDynamicMessageSerialization() throws Exception {
+    Message.Builder builder =
+      DynamicMessage.newBuilder(TestAllTypes.getDescriptor());
+    reflectionTester.setAllFieldsViaReflection(builder);
+    Message message = builder.build();
+
+    ByteString rawBytes = message.toByteString();
+    TestAllTypes message2 = TestAllTypes.parseFrom(rawBytes);
+
+    TestUtil.assertAllFieldsSet(message2);
+
+    // In fact, the serialized forms should be exactly the same, byte-for-byte.
+    assertEquals(TestUtil.getAllSet().toByteString(), rawBytes);
+  }
+
+  public void testDynamicMessageParsing() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TestUtil.setAllFields(builder);
+    TestAllTypes message = builder.build();
+
+    ByteString rawBytes = message.toByteString();
+
+    Message message2 =
+      DynamicMessage.parseFrom(TestAllTypes.getDescriptor(), rawBytes);
+    reflectionTester.assertAllFieldsSetViaReflection(message2);
+  }
+
+  public void testDynamicMessagePackedSerialization() throws Exception {
+    Message.Builder builder =
+        DynamicMessage.newBuilder(TestPackedTypes.getDescriptor());
+    packedReflectionTester.setPackedFieldsViaReflection(builder);
+    Message message = builder.build();
+
+    ByteString rawBytes = message.toByteString();
+    TestPackedTypes message2 = TestPackedTypes.parseFrom(rawBytes);
+
+    TestUtil.assertPackedFieldsSet(message2);
+
+    // In fact, the serialized forms should be exactly the same, byte-for-byte.
+    assertEquals(TestUtil.getPackedSet().toByteString(), rawBytes);
+  }
+
+  public void testDynamicMessagePackedParsing() throws Exception {
+    TestPackedTypes.Builder builder = TestPackedTypes.newBuilder();
+    TestUtil.setPackedFields(builder);
+    TestPackedTypes message = builder.build();
+
+    ByteString rawBytes = message.toByteString();
+
+    Message message2 =
+      DynamicMessage.parseFrom(TestPackedTypes.getDescriptor(), rawBytes);
+    packedReflectionTester.assertPackedFieldsSetViaReflection(message2);
+  }
+
+  public void testDynamicMessageCopy() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TestUtil.setAllFields(builder);
+    TestAllTypes message = builder.build();
+
+    DynamicMessage copy = DynamicMessage.newBuilder(message).build();
+    reflectionTester.assertAllFieldsSetViaReflection(copy);
+  }
+
+  public void testToBuilder() throws Exception {
+    DynamicMessage.Builder builder =
+        DynamicMessage.newBuilder(TestAllTypes.getDescriptor());
+    reflectionTester.setAllFieldsViaReflection(builder);
+    int unknownFieldNum = 9;
+    long unknownFieldVal = 90;
+    builder.setUnknownFields(UnknownFieldSet.newBuilder()
+        .addField(unknownFieldNum,
+            UnknownFieldSet.Field.newBuilder()
+                .addVarint(unknownFieldVal).build())
+        .build());
+    DynamicMessage message = builder.build();
+
+    DynamicMessage derived = message.toBuilder().build();
+    reflectionTester.assertAllFieldsSetViaReflection(derived);
+    assertEquals(Arrays.asList(unknownFieldVal),
+        derived.getUnknownFields().getField(unknownFieldNum).getVarintList());
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/GeneratedMessageTest.java b/java/src/test/java/com/google/protobuf/GeneratedMessageTest.java
new file mode 100644
index 0000000..cdf60c5
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/GeneratedMessageTest.java
@@ -0,0 +1,618 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import protobuf_unittest.UnittestOptimizeFor.TestOptimizedForSize;
+import protobuf_unittest.UnittestOptimizeFor.TestOptionalOptimizedForSize;
+import protobuf_unittest.UnittestOptimizeFor.TestRequiredOptimizedForSize;
+import protobuf_unittest.UnittestProto;
+import protobuf_unittest.UnittestProto.ForeignMessage;
+import protobuf_unittest.UnittestProto.ForeignEnum;
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestAllExtensions;
+import protobuf_unittest.UnittestProto.TestExtremeDefaultValues;
+import protobuf_unittest.MultipleFilesTestProto;
+import protobuf_unittest.MessageWithNoOuter;
+import protobuf_unittest.EnumWithNoOuter;
+import protobuf_unittest.ServiceWithNoOuter;
+import com.google.protobuf.UnittestLite;
+import com.google.protobuf.UnittestLite.TestAllExtensionsLite;
+
+import junit.framework.TestCase;
+import java.util.Arrays;
+
+/**
+ * Unit test for generated messages and generated code.  See also
+ * {@link MessageTest}, which tests some generated message functionality.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+public class GeneratedMessageTest extends TestCase {
+  TestUtil.ReflectionTester reflectionTester =
+    new TestUtil.ReflectionTester(TestAllTypes.getDescriptor(), null);
+
+  public void testDefaultInstance() throws Exception {
+    assertSame(TestAllTypes.getDefaultInstance(),
+               TestAllTypes.getDefaultInstance().getDefaultInstanceForType());
+    assertSame(TestAllTypes.getDefaultInstance(),
+               TestAllTypes.newBuilder().getDefaultInstanceForType());
+  }
+
+  public void testAccessors() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TestUtil.setAllFields(builder);
+    TestAllTypes message = builder.build();
+    TestUtil.assertAllFieldsSet(message);
+  }
+
+  public void testDoubleBuildError() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    builder.build();
+    try {
+      builder.build();
+      fail("Should have thrown exception.");
+    } catch (IllegalStateException e) {
+      // Success.
+    }
+  }
+
+  public void testClearAfterBuildError() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    builder.build();
+    try {
+      builder.clear();
+      fail("Should have thrown exception.");
+    } catch (IllegalStateException e) {
+      // Success.
+    }
+  }
+
+  public void testSettersRejectNull() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    try {
+      builder.setOptionalString(null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.setOptionalBytes(null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.setOptionalNestedMessage((TestAllTypes.NestedMessage) null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.setOptionalNestedMessage(
+          (TestAllTypes.NestedMessage.Builder) null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.setOptionalNestedEnum(null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.addRepeatedString(null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.addRepeatedBytes(null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.addRepeatedNestedMessage((TestAllTypes.NestedMessage) null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.addRepeatedNestedMessage(
+          (TestAllTypes.NestedMessage.Builder) null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.addRepeatedNestedEnum(null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+  }
+
+  public void testRepeatedSetters() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TestUtil.setAllFields(builder);
+    TestUtil.modifyRepeatedFields(builder);
+    TestAllTypes message = builder.build();
+    TestUtil.assertRepeatedFieldsModified(message);
+  }
+
+  public void testRepeatedSettersRejectNull() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+
+    builder.addRepeatedString("one");
+    builder.addRepeatedString("two");
+    try {
+      builder.setRepeatedString(1, null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+
+    builder.addRepeatedBytes(TestUtil.toBytes("one"));
+    builder.addRepeatedBytes(TestUtil.toBytes("two"));
+    try {
+      builder.setRepeatedBytes(1, null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+
+    builder.addRepeatedNestedMessage(
+      TestAllTypes.NestedMessage.newBuilder().setBb(218).build());
+    builder.addRepeatedNestedMessage(
+      TestAllTypes.NestedMessage.newBuilder().setBb(456).build());
+    try {
+      builder.setRepeatedNestedMessage(1, (TestAllTypes.NestedMessage) null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+    try {
+      builder.setRepeatedNestedMessage(
+          1, (TestAllTypes.NestedMessage.Builder) null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+
+    builder.addRepeatedNestedEnum(TestAllTypes.NestedEnum.FOO);
+    builder.addRepeatedNestedEnum(TestAllTypes.NestedEnum.BAR);
+    try {
+      builder.setRepeatedNestedEnum(1, null);
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+  }
+
+  public void testRepeatedAppend() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+
+    builder.addAllRepeatedInt32(Arrays.asList(1, 2, 3, 4));
+    builder.addAllRepeatedForeignEnum(Arrays.asList(ForeignEnum.FOREIGN_BAZ));
+
+    ForeignMessage foreignMessage =
+        ForeignMessage.newBuilder().setC(12).build();
+    builder.addAllRepeatedForeignMessage(Arrays.asList(foreignMessage));
+
+    TestAllTypes message = builder.build();
+    assertEquals(message.getRepeatedInt32List(), Arrays.asList(1, 2, 3, 4));
+    assertEquals(message.getRepeatedForeignEnumList(),
+        Arrays.asList(ForeignEnum.FOREIGN_BAZ));
+    assertEquals(1, message.getRepeatedForeignMessageCount());
+    assertEquals(12, message.getRepeatedForeignMessage(0).getC());
+  }
+
+  public void testRepeatedAppendRejectsNull() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+
+    ForeignMessage foreignMessage =
+        ForeignMessage.newBuilder().setC(12).build();
+    try {
+      builder.addAllRepeatedForeignMessage(
+          Arrays.asList(foreignMessage, (ForeignMessage) null));
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+
+    try {
+      builder.addAllRepeatedForeignEnum(
+          Arrays.asList(ForeignEnum.FOREIGN_BAZ, null));
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+
+    try {
+      builder.addAllRepeatedString(Arrays.asList("one", null));
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+
+    try {
+      builder.addAllRepeatedBytes(Arrays.asList(TestUtil.toBytes("one"), null));
+      fail("Exception was not thrown");
+    } catch (NullPointerException e) {
+      // We expect this exception.
+    }
+  }
+
+  public void testSettingForeignMessageUsingBuilder() throws Exception {
+    TestAllTypes message = TestAllTypes.newBuilder()
+        // Pass builder for foreign message instance.
+        .setOptionalForeignMessage(ForeignMessage.newBuilder().setC(123))
+        .build();
+    TestAllTypes expectedMessage = TestAllTypes.newBuilder()
+        // Create expected version passing foreign message instance explicitly.
+        .setOptionalForeignMessage(
+            ForeignMessage.newBuilder().setC(123).build())
+        .build();
+    // TODO(ngd): Upgrade to using real #equals method once implemented
+    assertEquals(expectedMessage.toString(), message.toString());
+  }
+
+  public void testSettingRepeatedForeignMessageUsingBuilder() throws Exception {
+    TestAllTypes message = TestAllTypes.newBuilder()
+        // Pass builder for foreign message instance.
+        .addRepeatedForeignMessage(ForeignMessage.newBuilder().setC(456))
+        .build();
+    TestAllTypes expectedMessage = TestAllTypes.newBuilder()
+        // Create expected version passing foreign message instance explicitly.
+        .addRepeatedForeignMessage(
+            ForeignMessage.newBuilder().setC(456).build())
+        .build();
+    assertEquals(expectedMessage.toString(), message.toString());
+  }
+
+  public void testDefaults() throws Exception {
+    TestUtil.assertClear(TestAllTypes.getDefaultInstance());
+    TestUtil.assertClear(TestAllTypes.newBuilder().build());
+
+    assertEquals("\u1234",
+                 TestExtremeDefaultValues.getDefaultInstance().getUtf8String());
+  }
+
+  public void testReflectionGetters() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TestUtil.setAllFields(builder);
+    TestAllTypes message = builder.build();
+    reflectionTester.assertAllFieldsSetViaReflection(message);
+  }
+
+  public void testReflectionSetters() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    reflectionTester.setAllFieldsViaReflection(builder);
+    TestAllTypes message = builder.build();
+    TestUtil.assertAllFieldsSet(message);
+  }
+
+  public void testReflectionSettersRejectNull() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    reflectionTester.assertReflectionSettersRejectNull(builder);
+  }
+
+  public void testReflectionRepeatedSetters() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    reflectionTester.setAllFieldsViaReflection(builder);
+    reflectionTester.modifyRepeatedFieldsViaReflection(builder);
+    TestAllTypes message = builder.build();
+    TestUtil.assertRepeatedFieldsModified(message);
+  }
+
+  public void testReflectionRepeatedSettersRejectNull() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    reflectionTester.assertReflectionRepeatedSettersRejectNull(builder);
+  }
+
+  public void testReflectionDefaults() throws Exception {
+    reflectionTester.assertClearViaReflection(
+      TestAllTypes.getDefaultInstance());
+    reflectionTester.assertClearViaReflection(
+      TestAllTypes.newBuilder().build());
+  }
+
+  public void testEnumInterface() throws Exception {
+    assertTrue(TestAllTypes.getDefaultInstance().getDefaultNestedEnum()
+        instanceof ProtocolMessageEnum);
+  }
+
+  public void testEnumMap() throws Exception {
+    Internal.EnumLiteMap<ForeignEnum> map = ForeignEnum.internalGetValueMap();
+
+    for (ForeignEnum value : ForeignEnum.values()) {
+      assertEquals(value, map.findValueByNumber(value.getNumber()));
+    }
+
+    assertTrue(map.findValueByNumber(12345) == null);
+  }
+
+  // =================================================================
+  // Extensions.
+
+  TestUtil.ReflectionTester extensionsReflectionTester =
+    new TestUtil.ReflectionTester(TestAllExtensions.getDescriptor(),
+                                  TestUtil.getExtensionRegistry());
+
+  public void testExtensionAccessors() throws Exception {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+    TestUtil.setAllExtensions(builder);
+    TestAllExtensions message = builder.build();
+    TestUtil.assertAllExtensionsSet(message);
+  }
+
+  public void testExtensionRepeatedSetters() throws Exception {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+    TestUtil.setAllExtensions(builder);
+    TestUtil.modifyRepeatedExtensions(builder);
+    TestAllExtensions message = builder.build();
+    TestUtil.assertRepeatedExtensionsModified(message);
+  }
+
+  public void testExtensionDefaults() throws Exception {
+    TestUtil.assertExtensionsClear(TestAllExtensions.getDefaultInstance());
+    TestUtil.assertExtensionsClear(TestAllExtensions.newBuilder().build());
+  }
+
+  public void testExtensionReflectionGetters() throws Exception {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+    TestUtil.setAllExtensions(builder);
+    TestAllExtensions message = builder.build();
+    extensionsReflectionTester.assertAllFieldsSetViaReflection(message);
+  }
+
+  public void testExtensionReflectionSetters() throws Exception {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+    extensionsReflectionTester.setAllFieldsViaReflection(builder);
+    TestAllExtensions message = builder.build();
+    TestUtil.assertAllExtensionsSet(message);
+  }
+
+  public void testExtensionReflectionSettersRejectNull() throws Exception {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+    extensionsReflectionTester.assertReflectionSettersRejectNull(builder);
+  }
+
+  public void testExtensionReflectionRepeatedSetters() throws Exception {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+    extensionsReflectionTester.setAllFieldsViaReflection(builder);
+    extensionsReflectionTester.modifyRepeatedFieldsViaReflection(builder);
+    TestAllExtensions message = builder.build();
+    TestUtil.assertRepeatedExtensionsModified(message);
+  }
+
+  public void testExtensionReflectionRepeatedSettersRejectNull()
+      throws Exception {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+    extensionsReflectionTester.assertReflectionRepeatedSettersRejectNull(
+        builder);
+  }
+
+  public void testExtensionReflectionDefaults() throws Exception {
+    extensionsReflectionTester.assertClearViaReflection(
+      TestAllExtensions.getDefaultInstance());
+    extensionsReflectionTester.assertClearViaReflection(
+      TestAllExtensions.newBuilder().build());
+  }
+
+  public void testClearExtension() throws Exception {
+    // clearExtension() is not actually used in TestUtil, so try it manually.
+    assertFalse(
+      TestAllExtensions.newBuilder()
+        .setExtension(UnittestProto.optionalInt32Extension, 1)
+        .clearExtension(UnittestProto.optionalInt32Extension)
+        .hasExtension(UnittestProto.optionalInt32Extension));
+    assertEquals(0,
+      TestAllExtensions.newBuilder()
+        .addExtension(UnittestProto.repeatedInt32Extension, 1)
+        .clearExtension(UnittestProto.repeatedInt32Extension)
+        .getExtensionCount(UnittestProto.repeatedInt32Extension));
+  }
+
+  public void testExtensionCopy() throws Exception {
+    TestAllExtensions original = TestUtil.getAllExtensionsSet();
+    TestAllExtensions copy = TestAllExtensions.newBuilder(original).build();
+    TestUtil.assertAllExtensionsSet(copy);
+  }
+
+  public void testExtensionMergeFrom() throws Exception {
+    TestAllExtensions original =
+      TestAllExtensions.newBuilder()
+        .setExtension(UnittestProto.optionalInt32Extension, 1).build();
+    TestAllExtensions merged =
+        TestAllExtensions.newBuilder().mergeFrom(original).build();
+    assertTrue(merged.hasExtension(UnittestProto.optionalInt32Extension));
+    assertEquals(
+        1, (int) merged.getExtension(UnittestProto.optionalInt32Extension));
+  }
+
+  // =================================================================
+  // Lite Extensions.
+
+  // We test lite extensions directly because they have a separate
+  // implementation from full extensions.  In contrast, we do not test
+  // lite fields directly since they are implemented exactly the same as
+  // regular fields.
+
+  public void testLiteExtensionAccessors() throws Exception {
+    TestAllExtensionsLite.Builder builder = TestAllExtensionsLite.newBuilder();
+    TestUtil.setAllExtensions(builder);
+    TestAllExtensionsLite message = builder.build();
+    TestUtil.assertAllExtensionsSet(message);
+  }
+
+  public void testLiteExtensionRepeatedSetters() throws Exception {
+    TestAllExtensionsLite.Builder builder = TestAllExtensionsLite.newBuilder();
+    TestUtil.setAllExtensions(builder);
+    TestUtil.modifyRepeatedExtensions(builder);
+    TestAllExtensionsLite message = builder.build();
+    TestUtil.assertRepeatedExtensionsModified(message);
+  }
+
+  public void testLiteExtensionDefaults() throws Exception {
+    TestUtil.assertExtensionsClear(TestAllExtensionsLite.getDefaultInstance());
+    TestUtil.assertExtensionsClear(TestAllExtensionsLite.newBuilder().build());
+  }
+
+  public void testClearLiteExtension() throws Exception {
+    // clearExtension() is not actually used in TestUtil, so try it manually.
+    assertFalse(
+      TestAllExtensionsLite.newBuilder()
+        .setExtension(UnittestLite.optionalInt32ExtensionLite, 1)
+        .clearExtension(UnittestLite.optionalInt32ExtensionLite)
+        .hasExtension(UnittestLite.optionalInt32ExtensionLite));
+    assertEquals(0,
+      TestAllExtensionsLite.newBuilder()
+        .addExtension(UnittestLite.repeatedInt32ExtensionLite, 1)
+        .clearExtension(UnittestLite.repeatedInt32ExtensionLite)
+        .getExtensionCount(UnittestLite.repeatedInt32ExtensionLite));
+  }
+
+  public void testLiteExtensionCopy() throws Exception {
+    TestAllExtensionsLite original = TestUtil.getAllLiteExtensionsSet();
+    TestAllExtensionsLite copy =
+        TestAllExtensionsLite.newBuilder(original).build();
+    TestUtil.assertAllExtensionsSet(copy);
+  }
+
+  public void testLiteExtensionMergeFrom() throws Exception {
+    TestAllExtensionsLite original =
+      TestAllExtensionsLite.newBuilder()
+        .setExtension(UnittestLite.optionalInt32ExtensionLite, 1).build();
+    TestAllExtensionsLite merged =
+        TestAllExtensionsLite.newBuilder().mergeFrom(original).build();
+    assertTrue(merged.hasExtension(UnittestLite.optionalInt32ExtensionLite));
+    assertEquals(
+        1, (int) merged.getExtension(UnittestLite.optionalInt32ExtensionLite));
+  }
+
+  // =================================================================
+  // multiple_files_test
+
+  public void testMultipleFilesOption() throws Exception {
+    // We mostly just want to check that things compile.
+    MessageWithNoOuter message =
+      MessageWithNoOuter.newBuilder()
+        .setNested(MessageWithNoOuter.NestedMessage.newBuilder().setI(1))
+        .addForeign(TestAllTypes.newBuilder().setOptionalInt32(1))
+        .setNestedEnum(MessageWithNoOuter.NestedEnum.BAZ)
+        .setForeignEnum(EnumWithNoOuter.BAR)
+        .build();
+    assertEquals(message, MessageWithNoOuter.parseFrom(message.toByteString()));
+
+    assertEquals(MultipleFilesTestProto.getDescriptor(),
+                 MessageWithNoOuter.getDescriptor().getFile());
+
+    Descriptors.FieldDescriptor field =
+      MessageWithNoOuter.getDescriptor().findFieldByName("foreign_enum");
+    assertEquals(EnumWithNoOuter.BAR.getValueDescriptor(),
+                 message.getField(field));
+
+    assertEquals(MultipleFilesTestProto.getDescriptor(),
+                 ServiceWithNoOuter.getDescriptor().getFile());
+
+    assertFalse(
+      TestAllExtensions.getDefaultInstance().hasExtension(
+        MultipleFilesTestProto.extensionWithOuter));
+  }
+
+  public void testOptionalFieldWithRequiredSubfieldsOptimizedForSize()
+    throws Exception {
+    TestOptionalOptimizedForSize message =
+        TestOptionalOptimizedForSize.getDefaultInstance();
+    assertTrue(message.isInitialized());
+
+    message = TestOptionalOptimizedForSize.newBuilder().setO(
+        TestRequiredOptimizedForSize.newBuilder().buildPartial()
+        ).buildPartial();
+    assertFalse(message.isInitialized());
+
+    message = TestOptionalOptimizedForSize.newBuilder().setO(
+        TestRequiredOptimizedForSize.newBuilder().setX(5).buildPartial()
+        ).buildPartial();
+    assertTrue(message.isInitialized());
+  }
+
+  public void testUninitializedExtensionInOptimizedForSize()
+      throws Exception {
+    TestOptimizedForSize.Builder builder = TestOptimizedForSize.newBuilder();
+    builder.setExtension(TestOptimizedForSize.testExtension2,
+        TestRequiredOptimizedForSize.newBuilder().buildPartial());
+    assertFalse(builder.isInitialized());
+    assertFalse(builder.buildPartial().isInitialized());
+
+    builder = TestOptimizedForSize.newBuilder();
+    builder.setExtension(TestOptimizedForSize.testExtension2,
+        TestRequiredOptimizedForSize.newBuilder().setX(10).buildPartial());
+    assertTrue(builder.isInitialized());
+    assertTrue(builder.buildPartial().isInitialized());
+  }
+
+  public void testToBuilder() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TestUtil.setAllFields(builder);
+    TestAllTypes message = builder.build();
+    TestUtil.assertAllFieldsSet(message.toBuilder().build());
+  }
+
+  public void testFieldConstantValues() throws Exception {
+    assertEquals(TestAllTypes.NestedMessage.BB_FIELD_NUMBER, 1);
+    assertEquals(TestAllTypes.OPTIONAL_INT32_FIELD_NUMBER, 1);
+    assertEquals(TestAllTypes.OPTIONALGROUP_FIELD_NUMBER, 16);
+    assertEquals(TestAllTypes.OPTIONAL_NESTED_MESSAGE_FIELD_NUMBER, 18);
+    assertEquals(TestAllTypes.OPTIONAL_NESTED_ENUM_FIELD_NUMBER, 21);
+    assertEquals(TestAllTypes.REPEATED_INT32_FIELD_NUMBER, 31);
+    assertEquals(TestAllTypes.REPEATEDGROUP_FIELD_NUMBER, 46);
+    assertEquals(TestAllTypes.REPEATED_NESTED_MESSAGE_FIELD_NUMBER, 48);
+    assertEquals(TestAllTypes.REPEATED_NESTED_ENUM_FIELD_NUMBER, 51);
+  }
+
+  public void testExtensionConstantValues() throws Exception {
+    assertEquals(UnittestProto.TestRequired.SINGLE_FIELD_NUMBER, 1000);
+    assertEquals(UnittestProto.TestRequired.MULTI_FIELD_NUMBER, 1001);
+    assertEquals(UnittestProto.OPTIONAL_INT32_EXTENSION_FIELD_NUMBER, 1);
+    assertEquals(UnittestProto.OPTIONALGROUP_EXTENSION_FIELD_NUMBER, 16);
+    assertEquals(
+      UnittestProto.OPTIONAL_NESTED_MESSAGE_EXTENSION_FIELD_NUMBER, 18);
+    assertEquals(UnittestProto.OPTIONAL_NESTED_ENUM_EXTENSION_FIELD_NUMBER, 21);
+    assertEquals(UnittestProto.REPEATED_INT32_EXTENSION_FIELD_NUMBER, 31);
+    assertEquals(UnittestProto.REPEATEDGROUP_EXTENSION_FIELD_NUMBER, 46);
+    assertEquals(
+      UnittestProto.REPEATED_NESTED_MESSAGE_EXTENSION_FIELD_NUMBER, 48);
+    assertEquals(UnittestProto.REPEATED_NESTED_ENUM_EXTENSION_FIELD_NUMBER, 51);
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/LiteTest.java b/java/src/test/java/com/google/protobuf/LiteTest.java
new file mode 100644
index 0000000..9dd730c
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/LiteTest.java
@@ -0,0 +1,114 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import com.google.protobuf.UnittestLite;
+import com.google.protobuf.UnittestLite.TestAllTypesLite;
+import com.google.protobuf.UnittestLite.TestAllExtensionsLite;
+import com.google.protobuf.UnittestLite.TestNestedExtensionLite;
+
+import junit.framework.TestCase;
+
+/**
+ * Test lite runtime.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+public class LiteTest extends TestCase {
+  public void setUp() throws Exception {
+    // Test that nested extensions are initialized correctly even if the outer
+    // class has not been accessed directly.  This was once a bug with lite
+    // messages.
+    //
+    // We put this in setUp() rather than in its own test method because we
+    // need to make sure it runs before any actual tests.
+    assertTrue(TestNestedExtensionLite.nestedExtension != null);
+  }
+
+  public void testLite() throws Exception {
+    // Since lite messages are a subset of regular messages, we can mostly
+    // assume that the functionality of lite messages is already thoroughly
+    // tested by the regular tests.  All this test really verifies is that
+    // a proto with optimize_for = LITE_RUNTIME compiles correctly when
+    // linked only against the lite library.  That is all tested at compile
+    // time, leaving not much to do in this method.  Let's just do some random
+    // stuff to make sure the lite message is actually here and usable.
+
+    TestAllTypesLite message =
+      TestAllTypesLite.newBuilder()
+                      .setOptionalInt32(123)
+                      .addRepeatedString("hello")
+                      .setOptionalNestedMessage(
+                          TestAllTypesLite.NestedMessage.newBuilder().setBb(7))
+                      .build();
+
+    ByteString data = message.toByteString();
+
+    TestAllTypesLite message2 = TestAllTypesLite.parseFrom(data);
+
+    assertEquals(123, message2.getOptionalInt32());
+    assertEquals(1, message2.getRepeatedStringCount());
+    assertEquals("hello", message2.getRepeatedString(0));
+    assertEquals(7, message2.getOptionalNestedMessage().getBb());
+  }
+
+  public void testLiteExtensions() throws Exception {
+    // TODO(kenton):  Unlike other features of the lite library, extensions are
+    //   implemented completely differently from the regular library.  We
+    //   need to test them more thoroughly, once they are fully-implemented.
+
+    TestAllExtensionsLite message =
+      TestAllExtensionsLite.newBuilder()
+        .setExtension(UnittestLite.optionalInt32ExtensionLite, 123)
+        .addExtension(UnittestLite.repeatedStringExtensionLite, "hello")
+        .setExtension(UnittestLite.optionalNestedEnumExtensionLite,
+            TestAllTypesLite.NestedEnum.BAZ)
+        .setExtension(UnittestLite.optionalNestedMessageExtensionLite,
+            TestAllTypesLite.NestedMessage.newBuilder().setBb(7).build())
+        .build();
+
+    // Test copying a message, since coping extensions actually does use a
+    // different code path between lite and regular libraries, and as of this
+    // writing, parsing hasn't been implemented yet.
+    TestAllExtensionsLite message2 = message.toBuilder().build();
+
+    assertEquals(123, (int) message2.getExtension(
+        UnittestLite.optionalInt32ExtensionLite));
+    assertEquals(1, message2.getExtensionCount(
+        UnittestLite.repeatedStringExtensionLite));
+    assertEquals("hello", message2.getExtension(
+        UnittestLite.repeatedStringExtensionLite, 0));
+    assertEquals(TestAllTypesLite.NestedEnum.BAZ, message2.getExtension(
+        UnittestLite.optionalNestedEnumExtensionLite));
+    assertEquals(7, message2.getExtension(
+        UnittestLite.optionalNestedMessageExtensionLite).getBb());
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/MessageTest.java b/java/src/test/java/com/google/protobuf/MessageTest.java
new file mode 100644
index 0000000..c2f47eb
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/MessageTest.java
@@ -0,0 +1,313 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestAllExtensions;
+import protobuf_unittest.UnittestProto.TestRequired;
+import protobuf_unittest.UnittestProto.TestRequiredForeign;
+import protobuf_unittest.UnittestProto.ForeignMessage;
+
+import junit.framework.TestCase;
+
+/**
+ * Misc. unit tests for message operations that apply to both generated
+ * and dynamic messages.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+public class MessageTest extends TestCase {
+  // =================================================================
+  // Message-merging tests.
+
+  static final TestAllTypes MERGE_SOURCE =
+    TestAllTypes.newBuilder()
+      .setOptionalInt32(1)
+      .setOptionalString("foo")
+      .setOptionalForeignMessage(ForeignMessage.getDefaultInstance())
+      .addRepeatedString("bar")
+      .build();
+
+  static final TestAllTypes MERGE_DEST =
+    TestAllTypes.newBuilder()
+      .setOptionalInt64(2)
+      .setOptionalString("baz")
+      .setOptionalForeignMessage(ForeignMessage.newBuilder().setC(3).build())
+      .addRepeatedString("qux")
+      .build();
+
+  static final String MERGE_RESULT_TEXT =
+      "optional_int32: 1\n" +
+      "optional_int64: 2\n" +
+      "optional_string: \"foo\"\n" +
+      "optional_foreign_message {\n" +
+      "  c: 3\n" +
+      "}\n" +
+      "repeated_string: \"qux\"\n" +
+      "repeated_string: \"bar\"\n";
+
+  public void testMergeFrom() throws Exception {
+    TestAllTypes result =
+      TestAllTypes.newBuilder(MERGE_DEST)
+        .mergeFrom(MERGE_SOURCE).build();
+
+    assertEquals(MERGE_RESULT_TEXT, result.toString());
+  }
+
+  /**
+   * Test merging a DynamicMessage into a GeneratedMessage.  As long as they
+   * have the same descriptor, this should work, but it is an entirely different
+   * code path.
+   */
+  public void testMergeFromDynamic() throws Exception {
+    TestAllTypes result =
+      TestAllTypes.newBuilder(MERGE_DEST)
+        .mergeFrom(DynamicMessage.newBuilder(MERGE_SOURCE).build())
+        .build();
+
+    assertEquals(MERGE_RESULT_TEXT, result.toString());
+  }
+
+  /** Test merging two DynamicMessages. */
+  public void testDynamicMergeFrom() throws Exception {
+    DynamicMessage result =
+      DynamicMessage.newBuilder(MERGE_DEST)
+        .mergeFrom(DynamicMessage.newBuilder(MERGE_SOURCE).build())
+        .build();
+
+    assertEquals(MERGE_RESULT_TEXT, result.toString());
+  }
+
+  // =================================================================
+  // Required-field-related tests.
+
+  private static final TestRequired TEST_REQUIRED_UNINITIALIZED =
+    TestRequired.getDefaultInstance();
+  private static final TestRequired TEST_REQUIRED_INITIALIZED =
+    TestRequired.newBuilder().setA(1).setB(2).setC(3).build();
+
+  public void testRequired() throws Exception {
+    TestRequired.Builder builder = TestRequired.newBuilder();
+
+    assertFalse(builder.isInitialized());
+    builder.setA(1);
+    assertFalse(builder.isInitialized());
+    builder.setB(1);
+    assertFalse(builder.isInitialized());
+    builder.setC(1);
+    assertTrue(builder.isInitialized());
+  }
+
+  public void testRequiredForeign() throws Exception {
+    TestRequiredForeign.Builder builder = TestRequiredForeign.newBuilder();
+
+    assertTrue(builder.isInitialized());
+
+    builder.setOptionalMessage(TEST_REQUIRED_UNINITIALIZED);
+    assertFalse(builder.isInitialized());
+
+    builder.setOptionalMessage(TEST_REQUIRED_INITIALIZED);
+    assertTrue(builder.isInitialized());
+
+    builder.addRepeatedMessage(TEST_REQUIRED_UNINITIALIZED);
+    assertFalse(builder.isInitialized());
+
+    builder.setRepeatedMessage(0, TEST_REQUIRED_INITIALIZED);
+    assertTrue(builder.isInitialized());
+  }
+
+  public void testRequiredExtension() throws Exception {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+
+    assertTrue(builder.isInitialized());
+
+    builder.setExtension(TestRequired.single, TEST_REQUIRED_UNINITIALIZED);
+    assertFalse(builder.isInitialized());
+
+    builder.setExtension(TestRequired.single, TEST_REQUIRED_INITIALIZED);
+    assertTrue(builder.isInitialized());
+
+    builder.addExtension(TestRequired.multi, TEST_REQUIRED_UNINITIALIZED);
+    assertFalse(builder.isInitialized());
+
+    builder.setExtension(TestRequired.multi, 0, TEST_REQUIRED_INITIALIZED);
+    assertTrue(builder.isInitialized());
+  }
+
+  public void testRequiredDynamic() throws Exception {
+    Descriptors.Descriptor descriptor = TestRequired.getDescriptor();
+    DynamicMessage.Builder builder = DynamicMessage.newBuilder(descriptor);
+
+    assertFalse(builder.isInitialized());
+    builder.setField(descriptor.findFieldByName("a"), 1);
+    assertFalse(builder.isInitialized());
+    builder.setField(descriptor.findFieldByName("b"), 1);
+    assertFalse(builder.isInitialized());
+    builder.setField(descriptor.findFieldByName("c"), 1);
+    assertTrue(builder.isInitialized());
+  }
+
+  public void testRequiredDynamicForeign() throws Exception {
+    Descriptors.Descriptor descriptor = TestRequiredForeign.getDescriptor();
+    DynamicMessage.Builder builder = DynamicMessage.newBuilder(descriptor);
+
+    assertTrue(builder.isInitialized());
+
+    builder.setField(descriptor.findFieldByName("optional_message"),
+                     TEST_REQUIRED_UNINITIALIZED);
+    assertFalse(builder.isInitialized());
+
+    builder.setField(descriptor.findFieldByName("optional_message"),
+                     TEST_REQUIRED_INITIALIZED);
+    assertTrue(builder.isInitialized());
+
+    builder.addRepeatedField(descriptor.findFieldByName("repeated_message"),
+                             TEST_REQUIRED_UNINITIALIZED);
+    assertFalse(builder.isInitialized());
+
+    builder.setRepeatedField(descriptor.findFieldByName("repeated_message"), 0,
+                             TEST_REQUIRED_INITIALIZED);
+    assertTrue(builder.isInitialized());
+  }
+
+  public void testUninitializedException() throws Exception {
+    try {
+      TestRequired.newBuilder().build();
+      fail("Should have thrown an exception.");
+    } catch (UninitializedMessageException e) {
+      assertEquals("Message missing required fields: a, b, c", e.getMessage());
+    }
+  }
+
+  public void testBuildPartial() throws Exception {
+    // We're mostly testing that no exception is thrown.
+    TestRequired message = TestRequired.newBuilder().buildPartial();
+    assertFalse(message.isInitialized());
+  }
+
+  public void testNestedUninitializedException() throws Exception {
+    try {
+      TestRequiredForeign.newBuilder()
+        .setOptionalMessage(TEST_REQUIRED_UNINITIALIZED)
+        .addRepeatedMessage(TEST_REQUIRED_UNINITIALIZED)
+        .addRepeatedMessage(TEST_REQUIRED_UNINITIALIZED)
+        .build();
+      fail("Should have thrown an exception.");
+    } catch (UninitializedMessageException e) {
+      assertEquals(
+        "Message missing required fields: " +
+        "optional_message.a, " +
+        "optional_message.b, " +
+        "optional_message.c, " +
+        "repeated_message[0].a, " +
+        "repeated_message[0].b, " +
+        "repeated_message[0].c, " +
+        "repeated_message[1].a, " +
+        "repeated_message[1].b, " +
+        "repeated_message[1].c",
+        e.getMessage());
+    }
+  }
+
+  public void testBuildNestedPartial() throws Exception {
+    // We're mostly testing that no exception is thrown.
+    TestRequiredForeign message =
+      TestRequiredForeign.newBuilder()
+        .setOptionalMessage(TEST_REQUIRED_UNINITIALIZED)
+        .addRepeatedMessage(TEST_REQUIRED_UNINITIALIZED)
+        .addRepeatedMessage(TEST_REQUIRED_UNINITIALIZED)
+        .buildPartial();
+    assertFalse(message.isInitialized());
+  }
+
+  public void testParseUnititialized() throws Exception {
+    try {
+      TestRequired.parseFrom(ByteString.EMPTY);
+      fail("Should have thrown an exception.");
+    } catch (InvalidProtocolBufferException e) {
+      assertEquals("Message missing required fields: a, b, c", e.getMessage());
+    }
+  }
+
+  public void testParseNestedUnititialized() throws Exception {
+    ByteString data =
+      TestRequiredForeign.newBuilder()
+        .setOptionalMessage(TEST_REQUIRED_UNINITIALIZED)
+        .addRepeatedMessage(TEST_REQUIRED_UNINITIALIZED)
+        .addRepeatedMessage(TEST_REQUIRED_UNINITIALIZED)
+        .buildPartial().toByteString();
+
+    try {
+      TestRequiredForeign.parseFrom(data);
+      fail("Should have thrown an exception.");
+    } catch (InvalidProtocolBufferException e) {
+      assertEquals(
+        "Message missing required fields: " +
+        "optional_message.a, " +
+        "optional_message.b, " +
+        "optional_message.c, " +
+        "repeated_message[0].a, " +
+        "repeated_message[0].b, " +
+        "repeated_message[0].c, " +
+        "repeated_message[1].a, " +
+        "repeated_message[1].b, " +
+        "repeated_message[1].c",
+        e.getMessage());
+    }
+  }
+
+  public void testDynamicUninitializedException() throws Exception {
+    try {
+      DynamicMessage.newBuilder(TestRequired.getDescriptor()).build();
+      fail("Should have thrown an exception.");
+    } catch (UninitializedMessageException e) {
+      assertEquals("Message missing required fields: a, b, c", e.getMessage());
+    }
+  }
+
+  public void testDynamicBuildPartial() throws Exception {
+    // We're mostly testing that no exception is thrown.
+    DynamicMessage message =
+      DynamicMessage.newBuilder(TestRequired.getDescriptor())
+        .buildPartial();
+    assertFalse(message.isInitialized());
+  }
+
+  public void testDynamicParseUnititialized() throws Exception {
+    try {
+      Descriptors.Descriptor descriptor = TestRequired.getDescriptor();
+      DynamicMessage.parseFrom(descriptor, ByteString.EMPTY);
+      fail("Should have thrown an exception.");
+    } catch (InvalidProtocolBufferException e) {
+      assertEquals("Message missing required fields: a, b, c", e.getMessage());
+    }
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/ServiceTest.java b/java/src/test/java/com/google/protobuf/ServiceTest.java
new file mode 100644
index 0000000..d8523ea
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/ServiceTest.java
@@ -0,0 +1,271 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import com.google.protobuf.Descriptors.MethodDescriptor;
+import protobuf_unittest.MessageWithNoOuter;
+import protobuf_unittest.ServiceWithNoOuter;
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestService;
+import protobuf_unittest.UnittestProto.FooRequest;
+import protobuf_unittest.UnittestProto.FooResponse;
+import protobuf_unittest.UnittestProto.BarRequest;
+import protobuf_unittest.UnittestProto.BarResponse;
+
+import org.easymock.classextension.EasyMock;
+import org.easymock.classextension.IMocksControl;
+import org.easymock.IArgumentMatcher;
+
+import junit.framework.TestCase;
+
+/**
+ * Tests services and stubs.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+public class ServiceTest extends TestCase {
+  private IMocksControl control;
+  private RpcController mockController;
+
+  private final Descriptors.MethodDescriptor fooDescriptor =
+    TestService.getDescriptor().getMethods().get(0);
+  private final Descriptors.MethodDescriptor barDescriptor =
+    TestService.getDescriptor().getMethods().get(1);
+
+  @Override
+  protected void setUp() throws Exception {
+    super.setUp();
+    control = EasyMock.createStrictControl();
+    mockController = control.createMock(RpcController.class);
+  }
+
+  // =================================================================
+
+  /** Tests Service.callMethod(). */
+  public void testCallMethod() throws Exception {
+    FooRequest fooRequest = FooRequest.newBuilder().build();
+    BarRequest barRequest = BarRequest.newBuilder().build();
+    MockCallback<Message> fooCallback = new MockCallback<Message>();
+    MockCallback<Message> barCallback = new MockCallback<Message>();
+    TestService mockService = control.createMock(TestService.class);
+
+    mockService.foo(EasyMock.same(mockController), EasyMock.same(fooRequest),
+                    this.<FooResponse>wrapsCallback(fooCallback));
+    mockService.bar(EasyMock.same(mockController), EasyMock.same(barRequest),
+                    this.<BarResponse>wrapsCallback(barCallback));
+    control.replay();
+
+    mockService.callMethod(fooDescriptor, mockController,
+                           fooRequest, fooCallback);
+    mockService.callMethod(barDescriptor, mockController,
+                           barRequest, barCallback);
+    control.verify();
+  }
+
+  /** Tests Service.get{Request,Response}Prototype(). */
+  public void testGetPrototype() throws Exception {
+    TestService mockService = control.createMock(TestService.class);
+
+    assertSame(mockService.getRequestPrototype(fooDescriptor),
+               FooRequest.getDefaultInstance());
+    assertSame(mockService.getResponsePrototype(fooDescriptor),
+               FooResponse.getDefaultInstance());
+    assertSame(mockService.getRequestPrototype(barDescriptor),
+               BarRequest.getDefaultInstance());
+    assertSame(mockService.getResponsePrototype(barDescriptor),
+               BarResponse.getDefaultInstance());
+  }
+
+  /** Tests generated stubs. */
+  public void testStub() throws Exception {
+    FooRequest fooRequest = FooRequest.newBuilder().build();
+    BarRequest barRequest = BarRequest.newBuilder().build();
+    MockCallback<FooResponse> fooCallback = new MockCallback<FooResponse>();
+    MockCallback<BarResponse> barCallback = new MockCallback<BarResponse>();
+    RpcChannel mockChannel = control.createMock(RpcChannel.class);
+    TestService stub = TestService.newStub(mockChannel);
+
+    mockChannel.callMethod(
+      EasyMock.same(fooDescriptor),
+      EasyMock.same(mockController),
+      EasyMock.same(fooRequest),
+      EasyMock.same(FooResponse.getDefaultInstance()),
+      this.<Message>wrapsCallback(fooCallback));
+    mockChannel.callMethod(
+      EasyMock.same(barDescriptor),
+      EasyMock.same(mockController),
+      EasyMock.same(barRequest),
+      EasyMock.same(BarResponse.getDefaultInstance()),
+      this.<Message>wrapsCallback(barCallback));
+    control.replay();
+
+    stub.foo(mockController, fooRequest, fooCallback);
+    stub.bar(mockController, barRequest, barCallback);
+    control.verify();
+  }
+
+  /** Tests generated blocking stubs. */
+  public void testBlockingStub() throws Exception {
+    FooRequest fooRequest = FooRequest.newBuilder().build();
+    BarRequest barRequest = BarRequest.newBuilder().build();
+    BlockingRpcChannel mockChannel =
+        control.createMock(BlockingRpcChannel.class);
+    TestService.BlockingInterface stub =
+        TestService.newBlockingStub(mockChannel);
+
+    FooResponse fooResponse = FooResponse.newBuilder().build();
+    BarResponse barResponse = BarResponse.newBuilder().build();
+
+    EasyMock.expect(mockChannel.callBlockingMethod(
+      EasyMock.same(fooDescriptor),
+      EasyMock.same(mockController),
+      EasyMock.same(fooRequest),
+      EasyMock.same(FooResponse.getDefaultInstance()))).andReturn(fooResponse);
+    EasyMock.expect(mockChannel.callBlockingMethod(
+      EasyMock.same(barDescriptor),
+      EasyMock.same(mockController),
+      EasyMock.same(barRequest),
+      EasyMock.same(BarResponse.getDefaultInstance()))).andReturn(barResponse);
+    control.replay();
+
+    assertSame(fooResponse, stub.foo(mockController, fooRequest));
+    assertSame(barResponse, stub.bar(mockController, barRequest));
+    control.verify();
+  }
+
+  public void testNewReflectiveService() {
+    ServiceWithNoOuter.Interface impl =
+        control.createMock(ServiceWithNoOuter.Interface.class);
+    RpcController controller = control.createMock(RpcController.class);
+    Service service = ServiceWithNoOuter.newReflectiveService(impl);
+
+    MethodDescriptor fooMethod =
+        ServiceWithNoOuter.getDescriptor().findMethodByName("Foo");
+    MessageWithNoOuter request = MessageWithNoOuter.getDefaultInstance();
+    RpcCallback<Message> callback = new RpcCallback<Message>() {
+      public void run(Message parameter) {
+        // No reason this should be run.
+        fail();
+      }
+    };
+    RpcCallback<TestAllTypes> specializedCallback =
+        RpcUtil.specializeCallback(callback);
+
+    impl.foo(EasyMock.same(controller), EasyMock.same(request),
+        EasyMock.same(specializedCallback));
+    EasyMock.expectLastCall();
+
+    control.replay();
+
+    service.callMethod(fooMethod, controller, request, callback);
+
+    control.verify();
+  }
+
+  public void testNewReflectiveBlockingService() throws ServiceException {
+    ServiceWithNoOuter.BlockingInterface impl =
+        control.createMock(ServiceWithNoOuter.BlockingInterface.class);
+    RpcController controller = control.createMock(RpcController.class);
+    BlockingService service =
+        ServiceWithNoOuter.newReflectiveBlockingService(impl);
+
+    MethodDescriptor fooMethod =
+        ServiceWithNoOuter.getDescriptor().findMethodByName("Foo");
+    MessageWithNoOuter request = MessageWithNoOuter.getDefaultInstance();
+    RpcCallback<Message> callback = new RpcCallback<Message>() {
+      public void run(Message parameter) {
+        // No reason this should be run.
+        fail();
+      }
+    };
+
+    TestAllTypes expectedResponse = TestAllTypes.getDefaultInstance();
+    EasyMock.expect(impl.foo(EasyMock.same(controller), EasyMock.same(request)))
+        .andReturn(expectedResponse);
+
+    control.replay();
+
+    Message response =
+        service.callBlockingMethod(fooMethod, controller, request);
+    assertEquals(expectedResponse, response);
+
+    control.verify();
+  }
+
+  // =================================================================
+
+  /**
+   * wrapsCallback() is an EasyMock argument predicate.  wrapsCallback(c)
+   * matches a callback if calling that callback causes c to be called.
+   * In other words, c wraps the given callback.
+   */
+  private <Type extends Message> RpcCallback<Type> wrapsCallback(
+      MockCallback<?> callback) {
+    EasyMock.reportMatcher(new WrapsCallback(callback));
+    return null;
+  }
+
+  /** The parameter to wrapsCallback() must be a MockCallback. */
+  private static class MockCallback<Type extends Message>
+      implements RpcCallback<Type> {
+    private boolean called = false;
+
+    public boolean isCalled() { return called; }
+
+    public void reset() { called = false; }
+    public void run(Type message) { called = true; }
+  }
+
+  /** Implementation of the wrapsCallback() argument matcher. */
+  private static class WrapsCallback implements IArgumentMatcher {
+    private MockCallback<?> callback;
+
+    public WrapsCallback(MockCallback<?> callback) {
+      this.callback = callback;
+    }
+
+    @SuppressWarnings("unchecked")
+    public boolean matches(Object actual) {
+      if (!(actual instanceof RpcCallback)) {
+        return false;
+      }
+      RpcCallback actualCallback = (RpcCallback)actual;
+
+      callback.reset();
+      actualCallback.run(null);
+      return callback.isCalled();
+    }
+
+    public void appendTo(StringBuffer buffer) {
+      buffer.append("wrapsCallback(mockCallback)");
+    }
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/TestUtil.java b/java/src/test/java/com/google/protobuf/TestUtil.java
new file mode 100644
index 0000000..805c42a
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/TestUtil.java
@@ -0,0 +1,3660 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import protobuf_unittest.UnittestProto;
+import com.google.protobuf.UnittestLite;
+
+// The static imports are to avoid 100+ char lines.  The following is roughly equivalent to
+// import static protobuf_unittest.UnittestProto.*;
+import static protobuf_unittest.UnittestProto.defaultInt32Extension;
+import static protobuf_unittest.UnittestProto.defaultInt64Extension;
+import static protobuf_unittest.UnittestProto.defaultUint32Extension;
+import static protobuf_unittest.UnittestProto.defaultUint64Extension;
+import static protobuf_unittest.UnittestProto.defaultSint32Extension;
+import static protobuf_unittest.UnittestProto.defaultSint64Extension;
+import static protobuf_unittest.UnittestProto.defaultFixed32Extension;
+import static protobuf_unittest.UnittestProto.defaultFixed64Extension;
+import static protobuf_unittest.UnittestProto.defaultSfixed32Extension;
+import static protobuf_unittest.UnittestProto.defaultSfixed64Extension;
+import static protobuf_unittest.UnittestProto.defaultFloatExtension;
+import static protobuf_unittest.UnittestProto.defaultDoubleExtension;
+import static protobuf_unittest.UnittestProto.defaultBoolExtension;
+import static protobuf_unittest.UnittestProto.defaultStringExtension;
+import static protobuf_unittest.UnittestProto.defaultBytesExtension;
+import static protobuf_unittest.UnittestProto.defaultNestedEnumExtension;
+import static protobuf_unittest.UnittestProto.defaultForeignEnumExtension;
+import static protobuf_unittest.UnittestProto.defaultImportEnumExtension;
+import static protobuf_unittest.UnittestProto.defaultStringPieceExtension;
+import static protobuf_unittest.UnittestProto.defaultCordExtension;
+
+import static protobuf_unittest.UnittestProto.optionalInt32Extension;
+import static protobuf_unittest.UnittestProto.optionalInt64Extension;
+import static protobuf_unittest.UnittestProto.optionalUint32Extension;
+import static protobuf_unittest.UnittestProto.optionalUint64Extension;
+import static protobuf_unittest.UnittestProto.optionalSint32Extension;
+import static protobuf_unittest.UnittestProto.optionalSint64Extension;
+import static protobuf_unittest.UnittestProto.optionalFixed32Extension;
+import static protobuf_unittest.UnittestProto.optionalFixed64Extension;
+import static protobuf_unittest.UnittestProto.optionalSfixed32Extension;
+import static protobuf_unittest.UnittestProto.optionalSfixed64Extension;
+import static protobuf_unittest.UnittestProto.optionalFloatExtension;
+import static protobuf_unittest.UnittestProto.optionalDoubleExtension;
+import static protobuf_unittest.UnittestProto.optionalBoolExtension;
+import static protobuf_unittest.UnittestProto.optionalStringExtension;
+import static protobuf_unittest.UnittestProto.optionalBytesExtension;
+import static protobuf_unittest.UnittestProto.optionalGroupExtension;
+import static protobuf_unittest.UnittestProto.optionalNestedMessageExtension;
+import static protobuf_unittest.UnittestProto.optionalForeignMessageExtension;
+import static protobuf_unittest.UnittestProto.optionalImportMessageExtension;
+import static protobuf_unittest.UnittestProto.optionalNestedEnumExtension;
+import static protobuf_unittest.UnittestProto.optionalForeignEnumExtension;
+import static protobuf_unittest.UnittestProto.optionalImportEnumExtension;
+import static protobuf_unittest.UnittestProto.optionalStringPieceExtension;
+import static protobuf_unittest.UnittestProto.optionalCordExtension;
+
+import static protobuf_unittest.UnittestProto.repeatedInt32Extension;
+import static protobuf_unittest.UnittestProto.repeatedInt64Extension;
+import static protobuf_unittest.UnittestProto.repeatedUint32Extension;
+import static protobuf_unittest.UnittestProto.repeatedUint64Extension;
+import static protobuf_unittest.UnittestProto.repeatedSint32Extension;
+import static protobuf_unittest.UnittestProto.repeatedSint64Extension;
+import static protobuf_unittest.UnittestProto.repeatedFixed32Extension;
+import static protobuf_unittest.UnittestProto.repeatedFixed64Extension;
+import static protobuf_unittest.UnittestProto.repeatedSfixed32Extension;
+import static protobuf_unittest.UnittestProto.repeatedSfixed64Extension;
+import static protobuf_unittest.UnittestProto.repeatedFloatExtension;
+import static protobuf_unittest.UnittestProto.repeatedDoubleExtension;
+import static protobuf_unittest.UnittestProto.repeatedBoolExtension;
+import static protobuf_unittest.UnittestProto.repeatedStringExtension;
+import static protobuf_unittest.UnittestProto.repeatedBytesExtension;
+import static protobuf_unittest.UnittestProto.repeatedGroupExtension;
+import static protobuf_unittest.UnittestProto.repeatedNestedMessageExtension;
+import static protobuf_unittest.UnittestProto.repeatedForeignMessageExtension;
+import static protobuf_unittest.UnittestProto.repeatedImportMessageExtension;
+import static protobuf_unittest.UnittestProto.repeatedNestedEnumExtension;
+import static protobuf_unittest.UnittestProto.repeatedForeignEnumExtension;
+import static protobuf_unittest.UnittestProto.repeatedImportEnumExtension;
+import static protobuf_unittest.UnittestProto.repeatedStringPieceExtension;
+import static protobuf_unittest.UnittestProto.repeatedCordExtension;
+
+import static protobuf_unittest.UnittestProto.OptionalGroup_extension;
+import static protobuf_unittest.UnittestProto.RepeatedGroup_extension;
+
+import static protobuf_unittest.UnittestProto.packedInt32Extension;
+import static protobuf_unittest.UnittestProto.packedInt64Extension;
+import static protobuf_unittest.UnittestProto.packedUint32Extension;
+import static protobuf_unittest.UnittestProto.packedUint64Extension;
+import static protobuf_unittest.UnittestProto.packedSint32Extension;
+import static protobuf_unittest.UnittestProto.packedSint64Extension;
+import static protobuf_unittest.UnittestProto.packedFixed32Extension;
+import static protobuf_unittest.UnittestProto.packedFixed64Extension;
+import static protobuf_unittest.UnittestProto.packedSfixed32Extension;
+import static protobuf_unittest.UnittestProto.packedSfixed64Extension;
+import static protobuf_unittest.UnittestProto.packedFloatExtension;
+import static protobuf_unittest.UnittestProto.packedDoubleExtension;
+import static protobuf_unittest.UnittestProto.packedBoolExtension;
+import static protobuf_unittest.UnittestProto.packedEnumExtension;
+
+import static com.google.protobuf.UnittestLite.defaultInt32ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultInt64ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultUint32ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultUint64ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultSint32ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultSint64ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultFixed32ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultFixed64ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultSfixed32ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultSfixed64ExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultFloatExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultDoubleExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultBoolExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultStringExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultBytesExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultNestedEnumExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultForeignEnumExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultImportEnumExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultStringPieceExtensionLite;
+import static com.google.protobuf.UnittestLite.defaultCordExtensionLite;
+
+import static com.google.protobuf.UnittestLite.optionalInt32ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalInt64ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalUint32ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalUint64ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalSint32ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalSint64ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalFixed32ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalFixed64ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalSfixed32ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalSfixed64ExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalFloatExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalDoubleExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalBoolExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalStringExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalBytesExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalGroupExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalNestedMessageExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalForeignMessageExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalImportMessageExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalNestedEnumExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalForeignEnumExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalImportEnumExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalStringPieceExtensionLite;
+import static com.google.protobuf.UnittestLite.optionalCordExtensionLite;
+
+import static com.google.protobuf.UnittestLite.repeatedInt32ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedInt64ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedUint32ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedUint64ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedSint32ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedSint64ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedFixed32ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedFixed64ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedSfixed32ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedSfixed64ExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedFloatExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedDoubleExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedBoolExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedStringExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedBytesExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedGroupExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedNestedMessageExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedForeignMessageExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedImportMessageExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedNestedEnumExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedForeignEnumExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedImportEnumExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedStringPieceExtensionLite;
+import static com.google.protobuf.UnittestLite.repeatedCordExtensionLite;
+
+import static com.google.protobuf.UnittestLite.OptionalGroup_extension_lite;
+import static com.google.protobuf.UnittestLite.RepeatedGroup_extension_lite;
+
+import static com.google.protobuf.UnittestLite.packedInt32ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedInt64ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedUint32ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedUint64ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedSint32ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedSint64ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedFixed32ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedFixed64ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedSfixed32ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedSfixed64ExtensionLite;
+import static com.google.protobuf.UnittestLite.packedFloatExtensionLite;
+import static com.google.protobuf.UnittestLite.packedDoubleExtensionLite;
+import static com.google.protobuf.UnittestLite.packedBoolExtensionLite;
+import static com.google.protobuf.UnittestLite.packedEnumExtensionLite;
+
+import protobuf_unittest.UnittestProto.TestAllExtensions;
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestPackedExtensions;
+import protobuf_unittest.UnittestProto.TestPackedTypes;
+import protobuf_unittest.UnittestProto.ForeignMessage;
+import protobuf_unittest.UnittestProto.ForeignEnum;
+import com.google.protobuf.test.UnittestImport.ImportMessage;
+import com.google.protobuf.test.UnittestImport.ImportEnum;
+
+import com.google.protobuf.UnittestLite.TestAllTypesLite;
+import com.google.protobuf.UnittestLite.TestAllExtensionsLite;
+import com.google.protobuf.UnittestLite.TestPackedExtensionsLite;
+import com.google.protobuf.UnittestLite.ForeignMessageLite;
+import com.google.protobuf.UnittestLite.ForeignEnumLite;
+import com.google.protobuf.UnittestImportLite.ImportMessageLite;
+import com.google.protobuf.UnittestImportLite.ImportEnumLite;
+
+import junit.framework.Assert;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+
+/**
+ * Contains methods for setting all fields of {@code TestAllTypes} to
+ * some vaules as well as checking that all the fields are set to those values.
+ * These are useful for testing various protocol message features, e.g.
+ * set all fields of a message, serialize it, parse it, and check that all
+ * fields are set.
+ *
+ * @author kenton@google.com Kenton Varda
+ */
+class TestUtil {
+  private TestUtil() {}
+
+  /** Helper to convert a String to ByteString. */
+  static ByteString toBytes(String str) {
+    try {
+      return ByteString.copyFrom(str.getBytes("UTF-8"));
+    } catch(java.io.UnsupportedEncodingException e) {
+      throw new RuntimeException("UTF-8 not supported.", e);
+    }
+  }
+
+  /**
+   * Get a {@code TestAllTypes} with all fields set as they would be by
+   * {@link #setAllFields(TestAllTypes.Builder)}.
+   */
+  public static TestAllTypes getAllSet() {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    setAllFields(builder);
+    return builder.build();
+  }
+
+  /**
+   * Get a {@code TestAllExtensions} with all fields set as they would be by
+   * {@link #setAllExtensions(TestAllExtensions.Builder)}.
+   */
+  public static TestAllExtensions getAllExtensionsSet() {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+    setAllExtensions(builder);
+    return builder.build();
+  }
+
+  public static TestAllExtensionsLite getAllLiteExtensionsSet() {
+    TestAllExtensionsLite.Builder builder = TestAllExtensionsLite.newBuilder();
+    setAllExtensions(builder);
+    return builder.build();
+  }
+
+  public static TestPackedTypes getPackedSet() {
+    TestPackedTypes.Builder builder = TestPackedTypes.newBuilder();
+    setPackedFields(builder);
+    return builder.build();
+  }
+
+  public static TestPackedExtensions getPackedExtensionsSet() {
+    TestPackedExtensions.Builder builder = TestPackedExtensions.newBuilder();
+    setPackedExtensions(builder);
+    return builder.build();
+  }
+
+  public static TestPackedExtensionsLite getLitePackedExtensionsSet() {
+    TestPackedExtensionsLite.Builder builder =
+        TestPackedExtensionsLite.newBuilder();
+    setPackedExtensions(builder);
+    return builder.build();
+  }
+
+  /**
+   * Set every field of {@code message} to the values expected by
+   * {@code assertAllFieldsSet()}.
+   */
+  public static void setAllFields(TestAllTypes.Builder message) {
+    message.setOptionalInt32   (101);
+    message.setOptionalInt64   (102);
+    message.setOptionalUint32  (103);
+    message.setOptionalUint64  (104);
+    message.setOptionalSint32  (105);
+    message.setOptionalSint64  (106);
+    message.setOptionalFixed32 (107);
+    message.setOptionalFixed64 (108);
+    message.setOptionalSfixed32(109);
+    message.setOptionalSfixed64(110);
+    message.setOptionalFloat   (111);
+    message.setOptionalDouble  (112);
+    message.setOptionalBool    (true);
+    message.setOptionalString  ("115");
+    message.setOptionalBytes   (toBytes("116"));
+
+    message.setOptionalGroup(
+      TestAllTypes.OptionalGroup.newBuilder().setA(117).build());
+    message.setOptionalNestedMessage(
+      TestAllTypes.NestedMessage.newBuilder().setBb(118).build());
+    message.setOptionalForeignMessage(
+      ForeignMessage.newBuilder().setC(119).build());
+    message.setOptionalImportMessage(
+      ImportMessage.newBuilder().setD(120).build());
+
+    message.setOptionalNestedEnum (TestAllTypes.NestedEnum.BAZ);
+    message.setOptionalForeignEnum(ForeignEnum.FOREIGN_BAZ);
+    message.setOptionalImportEnum (ImportEnum.IMPORT_BAZ);
+
+    message.setOptionalStringPiece("124");
+    message.setOptionalCord("125");
+
+    // -----------------------------------------------------------------
+
+    message.addRepeatedInt32   (201);
+    message.addRepeatedInt64   (202);
+    message.addRepeatedUint32  (203);
+    message.addRepeatedUint64  (204);
+    message.addRepeatedSint32  (205);
+    message.addRepeatedSint64  (206);
+    message.addRepeatedFixed32 (207);
+    message.addRepeatedFixed64 (208);
+    message.addRepeatedSfixed32(209);
+    message.addRepeatedSfixed64(210);
+    message.addRepeatedFloat   (211);
+    message.addRepeatedDouble  (212);
+    message.addRepeatedBool    (true);
+    message.addRepeatedString  ("215");
+    message.addRepeatedBytes   (toBytes("216"));
+
+    message.addRepeatedGroup(
+      TestAllTypes.RepeatedGroup.newBuilder().setA(217).build());
+    message.addRepeatedNestedMessage(
+      TestAllTypes.NestedMessage.newBuilder().setBb(218).build());
+    message.addRepeatedForeignMessage(
+      ForeignMessage.newBuilder().setC(219).build());
+    message.addRepeatedImportMessage(
+      ImportMessage.newBuilder().setD(220).build());
+
+    message.addRepeatedNestedEnum (TestAllTypes.NestedEnum.BAR);
+    message.addRepeatedForeignEnum(ForeignEnum.FOREIGN_BAR);
+    message.addRepeatedImportEnum (ImportEnum.IMPORT_BAR);
+
+    message.addRepeatedStringPiece("224");
+    message.addRepeatedCord("225");
+
+    // Add a second one of each field.
+    message.addRepeatedInt32   (301);
+    message.addRepeatedInt64   (302);
+    message.addRepeatedUint32  (303);
+    message.addRepeatedUint64  (304);
+    message.addRepeatedSint32  (305);
+    message.addRepeatedSint64  (306);
+    message.addRepeatedFixed32 (307);
+    message.addRepeatedFixed64 (308);
+    message.addRepeatedSfixed32(309);
+    message.addRepeatedSfixed64(310);
+    message.addRepeatedFloat   (311);
+    message.addRepeatedDouble  (312);
+    message.addRepeatedBool    (false);
+    message.addRepeatedString  ("315");
+    message.addRepeatedBytes   (toBytes("316"));
+
+    message.addRepeatedGroup(
+      TestAllTypes.RepeatedGroup.newBuilder().setA(317).build());
+    message.addRepeatedNestedMessage(
+      TestAllTypes.NestedMessage.newBuilder().setBb(318).build());
+    message.addRepeatedForeignMessage(
+      ForeignMessage.newBuilder().setC(319).build());
+    message.addRepeatedImportMessage(
+      ImportMessage.newBuilder().setD(320).build());
+
+    message.addRepeatedNestedEnum (TestAllTypes.NestedEnum.BAZ);
+    message.addRepeatedForeignEnum(ForeignEnum.FOREIGN_BAZ);
+    message.addRepeatedImportEnum (ImportEnum.IMPORT_BAZ);
+
+    message.addRepeatedStringPiece("324");
+    message.addRepeatedCord("325");
+
+    // -----------------------------------------------------------------
+
+    message.setDefaultInt32   (401);
+    message.setDefaultInt64   (402);
+    message.setDefaultUint32  (403);
+    message.setDefaultUint64  (404);
+    message.setDefaultSint32  (405);
+    message.setDefaultSint64  (406);
+    message.setDefaultFixed32 (407);
+    message.setDefaultFixed64 (408);
+    message.setDefaultSfixed32(409);
+    message.setDefaultSfixed64(410);
+    message.setDefaultFloat   (411);
+    message.setDefaultDouble  (412);
+    message.setDefaultBool    (false);
+    message.setDefaultString  ("415");
+    message.setDefaultBytes   (toBytes("416"));
+
+    message.setDefaultNestedEnum (TestAllTypes.NestedEnum.FOO);
+    message.setDefaultForeignEnum(ForeignEnum.FOREIGN_FOO);
+    message.setDefaultImportEnum (ImportEnum.IMPORT_FOO);
+
+    message.setDefaultStringPiece("424");
+    message.setDefaultCord("425");
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Modify the repeated fields of {@code message} to contain the values
+   * expected by {@code assertRepeatedFieldsModified()}.
+   */
+  public static void modifyRepeatedFields(TestAllTypes.Builder message) {
+    message.setRepeatedInt32   (1, 501);
+    message.setRepeatedInt64   (1, 502);
+    message.setRepeatedUint32  (1, 503);
+    message.setRepeatedUint64  (1, 504);
+    message.setRepeatedSint32  (1, 505);
+    message.setRepeatedSint64  (1, 506);
+    message.setRepeatedFixed32 (1, 507);
+    message.setRepeatedFixed64 (1, 508);
+    message.setRepeatedSfixed32(1, 509);
+    message.setRepeatedSfixed64(1, 510);
+    message.setRepeatedFloat   (1, 511);
+    message.setRepeatedDouble  (1, 512);
+    message.setRepeatedBool    (1, true);
+    message.setRepeatedString  (1, "515");
+    message.setRepeatedBytes   (1, toBytes("516"));
+
+    message.setRepeatedGroup(1,
+      TestAllTypes.RepeatedGroup.newBuilder().setA(517).build());
+    message.setRepeatedNestedMessage(1,
+      TestAllTypes.NestedMessage.newBuilder().setBb(518).build());
+    message.setRepeatedForeignMessage(1,
+      ForeignMessage.newBuilder().setC(519).build());
+    message.setRepeatedImportMessage(1,
+      ImportMessage.newBuilder().setD(520).build());
+
+    message.setRepeatedNestedEnum (1, TestAllTypes.NestedEnum.FOO);
+    message.setRepeatedForeignEnum(1, ForeignEnum.FOREIGN_FOO);
+    message.setRepeatedImportEnum (1, ImportEnum.IMPORT_FOO);
+
+    message.setRepeatedStringPiece(1, "524");
+    message.setRepeatedCord(1, "525");
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all fields of
+   * {@code message} are set to the values assigned by {@code setAllFields}.
+   */
+  public static void assertAllFieldsSet(TestAllTypes message) {
+    Assert.assertTrue(message.hasOptionalInt32   ());
+    Assert.assertTrue(message.hasOptionalInt64   ());
+    Assert.assertTrue(message.hasOptionalUint32  ());
+    Assert.assertTrue(message.hasOptionalUint64  ());
+    Assert.assertTrue(message.hasOptionalSint32  ());
+    Assert.assertTrue(message.hasOptionalSint64  ());
+    Assert.assertTrue(message.hasOptionalFixed32 ());
+    Assert.assertTrue(message.hasOptionalFixed64 ());
+    Assert.assertTrue(message.hasOptionalSfixed32());
+    Assert.assertTrue(message.hasOptionalSfixed64());
+    Assert.assertTrue(message.hasOptionalFloat   ());
+    Assert.assertTrue(message.hasOptionalDouble  ());
+    Assert.assertTrue(message.hasOptionalBool    ());
+    Assert.assertTrue(message.hasOptionalString  ());
+    Assert.assertTrue(message.hasOptionalBytes   ());
+
+    Assert.assertTrue(message.hasOptionalGroup         ());
+    Assert.assertTrue(message.hasOptionalNestedMessage ());
+    Assert.assertTrue(message.hasOptionalForeignMessage());
+    Assert.assertTrue(message.hasOptionalImportMessage ());
+
+    Assert.assertTrue(message.getOptionalGroup         ().hasA());
+    Assert.assertTrue(message.getOptionalNestedMessage ().hasBb());
+    Assert.assertTrue(message.getOptionalForeignMessage().hasC());
+    Assert.assertTrue(message.getOptionalImportMessage ().hasD());
+
+    Assert.assertTrue(message.hasOptionalNestedEnum ());
+    Assert.assertTrue(message.hasOptionalForeignEnum());
+    Assert.assertTrue(message.hasOptionalImportEnum ());
+
+    Assert.assertTrue(message.hasOptionalStringPiece());
+    Assert.assertTrue(message.hasOptionalCord());
+
+    Assert.assertEquals(101  , message.getOptionalInt32   ());
+    Assert.assertEquals(102  , message.getOptionalInt64   ());
+    Assert.assertEquals(103  , message.getOptionalUint32  ());
+    Assert.assertEquals(104  , message.getOptionalUint64  ());
+    Assert.assertEquals(105  , message.getOptionalSint32  ());
+    Assert.assertEquals(106  , message.getOptionalSint64  ());
+    Assert.assertEquals(107  , message.getOptionalFixed32 ());
+    Assert.assertEquals(108  , message.getOptionalFixed64 ());
+    Assert.assertEquals(109  , message.getOptionalSfixed32());
+    Assert.assertEquals(110  , message.getOptionalSfixed64());
+    Assert.assertEquals(111  , message.getOptionalFloat   (), 0.0);
+    Assert.assertEquals(112  , message.getOptionalDouble  (), 0.0);
+    Assert.assertEquals(true , message.getOptionalBool    ());
+    Assert.assertEquals("115", message.getOptionalString  ());
+    Assert.assertEquals(toBytes("116"), message.getOptionalBytes());
+
+    Assert.assertEquals(117, message.getOptionalGroup         ().getA());
+    Assert.assertEquals(118, message.getOptionalNestedMessage ().getBb());
+    Assert.assertEquals(119, message.getOptionalForeignMessage().getC());
+    Assert.assertEquals(120, message.getOptionalImportMessage ().getD());
+
+    Assert.assertEquals(TestAllTypes.NestedEnum.BAZ, message.getOptionalNestedEnum());
+    Assert.assertEquals(ForeignEnum.FOREIGN_BAZ, message.getOptionalForeignEnum());
+    Assert.assertEquals(ImportEnum.IMPORT_BAZ, message.getOptionalImportEnum());
+
+    Assert.assertEquals("124", message.getOptionalStringPiece());
+    Assert.assertEquals("125", message.getOptionalCord());
+
+    // -----------------------------------------------------------------
+
+    Assert.assertEquals(2, message.getRepeatedInt32Count   ());
+    Assert.assertEquals(2, message.getRepeatedInt64Count   ());
+    Assert.assertEquals(2, message.getRepeatedUint32Count  ());
+    Assert.assertEquals(2, message.getRepeatedUint64Count  ());
+    Assert.assertEquals(2, message.getRepeatedSint32Count  ());
+    Assert.assertEquals(2, message.getRepeatedSint64Count  ());
+    Assert.assertEquals(2, message.getRepeatedFixed32Count ());
+    Assert.assertEquals(2, message.getRepeatedFixed64Count ());
+    Assert.assertEquals(2, message.getRepeatedSfixed32Count());
+    Assert.assertEquals(2, message.getRepeatedSfixed64Count());
+    Assert.assertEquals(2, message.getRepeatedFloatCount   ());
+    Assert.assertEquals(2, message.getRepeatedDoubleCount  ());
+    Assert.assertEquals(2, message.getRepeatedBoolCount    ());
+    Assert.assertEquals(2, message.getRepeatedStringCount  ());
+    Assert.assertEquals(2, message.getRepeatedBytesCount   ());
+
+    Assert.assertEquals(2, message.getRepeatedGroupCount         ());
+    Assert.assertEquals(2, message.getRepeatedNestedMessageCount ());
+    Assert.assertEquals(2, message.getRepeatedForeignMessageCount());
+    Assert.assertEquals(2, message.getRepeatedImportMessageCount ());
+    Assert.assertEquals(2, message.getRepeatedNestedEnumCount    ());
+    Assert.assertEquals(2, message.getRepeatedForeignEnumCount   ());
+    Assert.assertEquals(2, message.getRepeatedImportEnumCount    ());
+
+    Assert.assertEquals(2, message.getRepeatedStringPieceCount());
+    Assert.assertEquals(2, message.getRepeatedCordCount());
+
+    Assert.assertEquals(201  , message.getRepeatedInt32   (0));
+    Assert.assertEquals(202  , message.getRepeatedInt64   (0));
+    Assert.assertEquals(203  , message.getRepeatedUint32  (0));
+    Assert.assertEquals(204  , message.getRepeatedUint64  (0));
+    Assert.assertEquals(205  , message.getRepeatedSint32  (0));
+    Assert.assertEquals(206  , message.getRepeatedSint64  (0));
+    Assert.assertEquals(207  , message.getRepeatedFixed32 (0));
+    Assert.assertEquals(208  , message.getRepeatedFixed64 (0));
+    Assert.assertEquals(209  , message.getRepeatedSfixed32(0));
+    Assert.assertEquals(210  , message.getRepeatedSfixed64(0));
+    Assert.assertEquals(211  , message.getRepeatedFloat   (0), 0.0);
+    Assert.assertEquals(212  , message.getRepeatedDouble  (0), 0.0);
+    Assert.assertEquals(true , message.getRepeatedBool    (0));
+    Assert.assertEquals("215", message.getRepeatedString  (0));
+    Assert.assertEquals(toBytes("216"), message.getRepeatedBytes(0));
+
+    Assert.assertEquals(217, message.getRepeatedGroup         (0).getA());
+    Assert.assertEquals(218, message.getRepeatedNestedMessage (0).getBb());
+    Assert.assertEquals(219, message.getRepeatedForeignMessage(0).getC());
+    Assert.assertEquals(220, message.getRepeatedImportMessage (0).getD());
+
+    Assert.assertEquals(TestAllTypes.NestedEnum.BAR, message.getRepeatedNestedEnum (0));
+    Assert.assertEquals(ForeignEnum.FOREIGN_BAR, message.getRepeatedForeignEnum(0));
+    Assert.assertEquals(ImportEnum.IMPORT_BAR, message.getRepeatedImportEnum(0));
+
+    Assert.assertEquals("224", message.getRepeatedStringPiece(0));
+    Assert.assertEquals("225", message.getRepeatedCord(0));
+
+    Assert.assertEquals(301  , message.getRepeatedInt32   (1));
+    Assert.assertEquals(302  , message.getRepeatedInt64   (1));
+    Assert.assertEquals(303  , message.getRepeatedUint32  (1));
+    Assert.assertEquals(304  , message.getRepeatedUint64  (1));
+    Assert.assertEquals(305  , message.getRepeatedSint32  (1));
+    Assert.assertEquals(306  , message.getRepeatedSint64  (1));
+    Assert.assertEquals(307  , message.getRepeatedFixed32 (1));
+    Assert.assertEquals(308  , message.getRepeatedFixed64 (1));
+    Assert.assertEquals(309  , message.getRepeatedSfixed32(1));
+    Assert.assertEquals(310  , message.getRepeatedSfixed64(1));
+    Assert.assertEquals(311  , message.getRepeatedFloat   (1), 0.0);
+    Assert.assertEquals(312  , message.getRepeatedDouble  (1), 0.0);
+    Assert.assertEquals(false, message.getRepeatedBool    (1));
+    Assert.assertEquals("315", message.getRepeatedString  (1));
+    Assert.assertEquals(toBytes("316"), message.getRepeatedBytes(1));
+
+    Assert.assertEquals(317, message.getRepeatedGroup         (1).getA());
+    Assert.assertEquals(318, message.getRepeatedNestedMessage (1).getBb());
+    Assert.assertEquals(319, message.getRepeatedForeignMessage(1).getC());
+    Assert.assertEquals(320, message.getRepeatedImportMessage (1).getD());
+
+    Assert.assertEquals(TestAllTypes.NestedEnum.BAZ, message.getRepeatedNestedEnum (1));
+    Assert.assertEquals(ForeignEnum.FOREIGN_BAZ, message.getRepeatedForeignEnum(1));
+    Assert.assertEquals(ImportEnum.IMPORT_BAZ, message.getRepeatedImportEnum(1));
+
+    Assert.assertEquals("324", message.getRepeatedStringPiece(1));
+    Assert.assertEquals("325", message.getRepeatedCord(1));
+
+    // -----------------------------------------------------------------
+
+    Assert.assertTrue(message.hasDefaultInt32   ());
+    Assert.assertTrue(message.hasDefaultInt64   ());
+    Assert.assertTrue(message.hasDefaultUint32  ());
+    Assert.assertTrue(message.hasDefaultUint64  ());
+    Assert.assertTrue(message.hasDefaultSint32  ());
+    Assert.assertTrue(message.hasDefaultSint64  ());
+    Assert.assertTrue(message.hasDefaultFixed32 ());
+    Assert.assertTrue(message.hasDefaultFixed64 ());
+    Assert.assertTrue(message.hasDefaultSfixed32());
+    Assert.assertTrue(message.hasDefaultSfixed64());
+    Assert.assertTrue(message.hasDefaultFloat   ());
+    Assert.assertTrue(message.hasDefaultDouble  ());
+    Assert.assertTrue(message.hasDefaultBool    ());
+    Assert.assertTrue(message.hasDefaultString  ());
+    Assert.assertTrue(message.hasDefaultBytes   ());
+
+    Assert.assertTrue(message.hasDefaultNestedEnum ());
+    Assert.assertTrue(message.hasDefaultForeignEnum());
+    Assert.assertTrue(message.hasDefaultImportEnum ());
+
+    Assert.assertTrue(message.hasDefaultStringPiece());
+    Assert.assertTrue(message.hasDefaultCord());
+
+    Assert.assertEquals(401  , message.getDefaultInt32   ());
+    Assert.assertEquals(402  , message.getDefaultInt64   ());
+    Assert.assertEquals(403  , message.getDefaultUint32  ());
+    Assert.assertEquals(404  , message.getDefaultUint64  ());
+    Assert.assertEquals(405  , message.getDefaultSint32  ());
+    Assert.assertEquals(406  , message.getDefaultSint64  ());
+    Assert.assertEquals(407  , message.getDefaultFixed32 ());
+    Assert.assertEquals(408  , message.getDefaultFixed64 ());
+    Assert.assertEquals(409  , message.getDefaultSfixed32());
+    Assert.assertEquals(410  , message.getDefaultSfixed64());
+    Assert.assertEquals(411  , message.getDefaultFloat   (), 0.0);
+    Assert.assertEquals(412  , message.getDefaultDouble  (), 0.0);
+    Assert.assertEquals(false, message.getDefaultBool    ());
+    Assert.assertEquals("415", message.getDefaultString  ());
+    Assert.assertEquals(toBytes("416"), message.getDefaultBytes());
+
+    Assert.assertEquals(TestAllTypes.NestedEnum.FOO, message.getDefaultNestedEnum ());
+    Assert.assertEquals(ForeignEnum.FOREIGN_FOO, message.getDefaultForeignEnum());
+    Assert.assertEquals(ImportEnum.IMPORT_FOO, message.getDefaultImportEnum());
+
+    Assert.assertEquals("424", message.getDefaultStringPiece());
+    Assert.assertEquals("425", message.getDefaultCord());
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all fields of
+   * {@code message} are cleared, and that getting the fields returns their
+   * default values.
+   */
+  public static void assertClear(TestAllTypes message) {
+    // hasBlah() should initially be false for all optional fields.
+    Assert.assertFalse(message.hasOptionalInt32   ());
+    Assert.assertFalse(message.hasOptionalInt64   ());
+    Assert.assertFalse(message.hasOptionalUint32  ());
+    Assert.assertFalse(message.hasOptionalUint64  ());
+    Assert.assertFalse(message.hasOptionalSint32  ());
+    Assert.assertFalse(message.hasOptionalSint64  ());
+    Assert.assertFalse(message.hasOptionalFixed32 ());
+    Assert.assertFalse(message.hasOptionalFixed64 ());
+    Assert.assertFalse(message.hasOptionalSfixed32());
+    Assert.assertFalse(message.hasOptionalSfixed64());
+    Assert.assertFalse(message.hasOptionalFloat   ());
+    Assert.assertFalse(message.hasOptionalDouble  ());
+    Assert.assertFalse(message.hasOptionalBool    ());
+    Assert.assertFalse(message.hasOptionalString  ());
+    Assert.assertFalse(message.hasOptionalBytes   ());
+
+    Assert.assertFalse(message.hasOptionalGroup         ());
+    Assert.assertFalse(message.hasOptionalNestedMessage ());
+    Assert.assertFalse(message.hasOptionalForeignMessage());
+    Assert.assertFalse(message.hasOptionalImportMessage ());
+
+    Assert.assertFalse(message.hasOptionalNestedEnum ());
+    Assert.assertFalse(message.hasOptionalForeignEnum());
+    Assert.assertFalse(message.hasOptionalImportEnum ());
+
+    Assert.assertFalse(message.hasOptionalStringPiece());
+    Assert.assertFalse(message.hasOptionalCord());
+
+    // Optional fields without defaults are set to zero or something like it.
+    Assert.assertEquals(0    , message.getOptionalInt32   ());
+    Assert.assertEquals(0    , message.getOptionalInt64   ());
+    Assert.assertEquals(0    , message.getOptionalUint32  ());
+    Assert.assertEquals(0    , message.getOptionalUint64  ());
+    Assert.assertEquals(0    , message.getOptionalSint32  ());
+    Assert.assertEquals(0    , message.getOptionalSint64  ());
+    Assert.assertEquals(0    , message.getOptionalFixed32 ());
+    Assert.assertEquals(0    , message.getOptionalFixed64 ());
+    Assert.assertEquals(0    , message.getOptionalSfixed32());
+    Assert.assertEquals(0    , message.getOptionalSfixed64());
+    Assert.assertEquals(0    , message.getOptionalFloat   (), 0.0);
+    Assert.assertEquals(0    , message.getOptionalDouble  (), 0.0);
+    Assert.assertEquals(false, message.getOptionalBool    ());
+    Assert.assertEquals(""   , message.getOptionalString  ());
+    Assert.assertEquals(ByteString.EMPTY, message.getOptionalBytes());
+
+    // Embedded messages should also be clear.
+    Assert.assertFalse(message.getOptionalGroup         ().hasA());
+    Assert.assertFalse(message.getOptionalNestedMessage ().hasBb());
+    Assert.assertFalse(message.getOptionalForeignMessage().hasC());
+    Assert.assertFalse(message.getOptionalImportMessage ().hasD());
+
+    Assert.assertEquals(0, message.getOptionalGroup         ().getA());
+    Assert.assertEquals(0, message.getOptionalNestedMessage ().getBb());
+    Assert.assertEquals(0, message.getOptionalForeignMessage().getC());
+    Assert.assertEquals(0, message.getOptionalImportMessage ().getD());
+
+    // Enums without defaults are set to the first value in the enum.
+    Assert.assertEquals(TestAllTypes.NestedEnum.FOO, message.getOptionalNestedEnum ());
+    Assert.assertEquals(ForeignEnum.FOREIGN_FOO, message.getOptionalForeignEnum());
+    Assert.assertEquals(ImportEnum.IMPORT_FOO, message.getOptionalImportEnum());
+
+    Assert.assertEquals("", message.getOptionalStringPiece());
+    Assert.assertEquals("", message.getOptionalCord());
+
+    // Repeated fields are empty.
+    Assert.assertEquals(0, message.getRepeatedInt32Count   ());
+    Assert.assertEquals(0, message.getRepeatedInt64Count   ());
+    Assert.assertEquals(0, message.getRepeatedUint32Count  ());
+    Assert.assertEquals(0, message.getRepeatedUint64Count  ());
+    Assert.assertEquals(0, message.getRepeatedSint32Count  ());
+    Assert.assertEquals(0, message.getRepeatedSint64Count  ());
+    Assert.assertEquals(0, message.getRepeatedFixed32Count ());
+    Assert.assertEquals(0, message.getRepeatedFixed64Count ());
+    Assert.assertEquals(0, message.getRepeatedSfixed32Count());
+    Assert.assertEquals(0, message.getRepeatedSfixed64Count());
+    Assert.assertEquals(0, message.getRepeatedFloatCount   ());
+    Assert.assertEquals(0, message.getRepeatedDoubleCount  ());
+    Assert.assertEquals(0, message.getRepeatedBoolCount    ());
+    Assert.assertEquals(0, message.getRepeatedStringCount  ());
+    Assert.assertEquals(0, message.getRepeatedBytesCount   ());
+
+    Assert.assertEquals(0, message.getRepeatedGroupCount         ());
+    Assert.assertEquals(0, message.getRepeatedNestedMessageCount ());
+    Assert.assertEquals(0, message.getRepeatedForeignMessageCount());
+    Assert.assertEquals(0, message.getRepeatedImportMessageCount ());
+    Assert.assertEquals(0, message.getRepeatedNestedEnumCount    ());
+    Assert.assertEquals(0, message.getRepeatedForeignEnumCount   ());
+    Assert.assertEquals(0, message.getRepeatedImportEnumCount    ());
+
+    Assert.assertEquals(0, message.getRepeatedStringPieceCount());
+    Assert.assertEquals(0, message.getRepeatedCordCount());
+
+    // hasBlah() should also be false for all default fields.
+    Assert.assertFalse(message.hasDefaultInt32   ());
+    Assert.assertFalse(message.hasDefaultInt64   ());
+    Assert.assertFalse(message.hasDefaultUint32  ());
+    Assert.assertFalse(message.hasDefaultUint64  ());
+    Assert.assertFalse(message.hasDefaultSint32  ());
+    Assert.assertFalse(message.hasDefaultSint64  ());
+    Assert.assertFalse(message.hasDefaultFixed32 ());
+    Assert.assertFalse(message.hasDefaultFixed64 ());
+    Assert.assertFalse(message.hasDefaultSfixed32());
+    Assert.assertFalse(message.hasDefaultSfixed64());
+    Assert.assertFalse(message.hasDefaultFloat   ());
+    Assert.assertFalse(message.hasDefaultDouble  ());
+    Assert.assertFalse(message.hasDefaultBool    ());
+    Assert.assertFalse(message.hasDefaultString  ());
+    Assert.assertFalse(message.hasDefaultBytes   ());
+
+    Assert.assertFalse(message.hasDefaultNestedEnum ());
+    Assert.assertFalse(message.hasDefaultForeignEnum());
+    Assert.assertFalse(message.hasDefaultImportEnum ());
+
+    Assert.assertFalse(message.hasDefaultStringPiece());
+    Assert.assertFalse(message.hasDefaultCord());
+
+    // Fields with defaults have their default values (duh).
+    Assert.assertEquals( 41    , message.getDefaultInt32   ());
+    Assert.assertEquals( 42    , message.getDefaultInt64   ());
+    Assert.assertEquals( 43    , message.getDefaultUint32  ());
+    Assert.assertEquals( 44    , message.getDefaultUint64  ());
+    Assert.assertEquals(-45    , message.getDefaultSint32  ());
+    Assert.assertEquals( 46    , message.getDefaultSint64  ());
+    Assert.assertEquals( 47    , message.getDefaultFixed32 ());
+    Assert.assertEquals( 48    , message.getDefaultFixed64 ());
+    Assert.assertEquals( 49    , message.getDefaultSfixed32());
+    Assert.assertEquals(-50    , message.getDefaultSfixed64());
+    Assert.assertEquals( 51.5  , message.getDefaultFloat   (), 0.0);
+    Assert.assertEquals( 52e3  , message.getDefaultDouble  (), 0.0);
+    Assert.assertEquals(true   , message.getDefaultBool    ());
+    Assert.assertEquals("hello", message.getDefaultString  ());
+    Assert.assertEquals(toBytes("world"), message.getDefaultBytes());
+
+    Assert.assertEquals(TestAllTypes.NestedEnum.BAR, message.getDefaultNestedEnum ());
+    Assert.assertEquals(ForeignEnum.FOREIGN_BAR, message.getDefaultForeignEnum());
+    Assert.assertEquals(ImportEnum.IMPORT_BAR, message.getDefaultImportEnum());
+
+    Assert.assertEquals("abc", message.getDefaultStringPiece());
+    Assert.assertEquals("123", message.getDefaultCord());
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all fields of
+   * {@code message} are set to the values assigned by {@code setAllFields}
+   * followed by {@code modifyRepeatedFields}.
+   */
+  public static void assertRepeatedFieldsModified(TestAllTypes message) {
+    // ModifyRepeatedFields only sets the second repeated element of each
+    // field.  In addition to verifying this, we also verify that the first
+    // element and size were *not* modified.
+    Assert.assertEquals(2, message.getRepeatedInt32Count   ());
+    Assert.assertEquals(2, message.getRepeatedInt64Count   ());
+    Assert.assertEquals(2, message.getRepeatedUint32Count  ());
+    Assert.assertEquals(2, message.getRepeatedUint64Count  ());
+    Assert.assertEquals(2, message.getRepeatedSint32Count  ());
+    Assert.assertEquals(2, message.getRepeatedSint64Count  ());
+    Assert.assertEquals(2, message.getRepeatedFixed32Count ());
+    Assert.assertEquals(2, message.getRepeatedFixed64Count ());
+    Assert.assertEquals(2, message.getRepeatedSfixed32Count());
+    Assert.assertEquals(2, message.getRepeatedSfixed64Count());
+    Assert.assertEquals(2, message.getRepeatedFloatCount   ());
+    Assert.assertEquals(2, message.getRepeatedDoubleCount  ());
+    Assert.assertEquals(2, message.getRepeatedBoolCount    ());
+    Assert.assertEquals(2, message.getRepeatedStringCount  ());
+    Assert.assertEquals(2, message.getRepeatedBytesCount   ());
+
+    Assert.assertEquals(2, message.getRepeatedGroupCount         ());
+    Assert.assertEquals(2, message.getRepeatedNestedMessageCount ());
+    Assert.assertEquals(2, message.getRepeatedForeignMessageCount());
+    Assert.assertEquals(2, message.getRepeatedImportMessageCount ());
+    Assert.assertEquals(2, message.getRepeatedNestedEnumCount    ());
+    Assert.assertEquals(2, message.getRepeatedForeignEnumCount   ());
+    Assert.assertEquals(2, message.getRepeatedImportEnumCount    ());
+
+    Assert.assertEquals(2, message.getRepeatedStringPieceCount());
+    Assert.assertEquals(2, message.getRepeatedCordCount());
+
+    Assert.assertEquals(201  , message.getRepeatedInt32   (0));
+    Assert.assertEquals(202L , message.getRepeatedInt64   (0));
+    Assert.assertEquals(203  , message.getRepeatedUint32  (0));
+    Assert.assertEquals(204L , message.getRepeatedUint64  (0));
+    Assert.assertEquals(205  , message.getRepeatedSint32  (0));
+    Assert.assertEquals(206L , message.getRepeatedSint64  (0));
+    Assert.assertEquals(207  , message.getRepeatedFixed32 (0));
+    Assert.assertEquals(208L , message.getRepeatedFixed64 (0));
+    Assert.assertEquals(209  , message.getRepeatedSfixed32(0));
+    Assert.assertEquals(210L , message.getRepeatedSfixed64(0));
+    Assert.assertEquals(211F , message.getRepeatedFloat   (0));
+    Assert.assertEquals(212D , message.getRepeatedDouble  (0));
+    Assert.assertEquals(true , message.getRepeatedBool    (0));
+    Assert.assertEquals("215", message.getRepeatedString  (0));
+    Assert.assertEquals(toBytes("216"), message.getRepeatedBytes(0));
+
+    Assert.assertEquals(217, message.getRepeatedGroup         (0).getA());
+    Assert.assertEquals(218, message.getRepeatedNestedMessage (0).getBb());
+    Assert.assertEquals(219, message.getRepeatedForeignMessage(0).getC());
+    Assert.assertEquals(220, message.getRepeatedImportMessage (0).getD());
+
+    Assert.assertEquals(TestAllTypes.NestedEnum.BAR, message.getRepeatedNestedEnum (0));
+    Assert.assertEquals(ForeignEnum.FOREIGN_BAR, message.getRepeatedForeignEnum(0));
+    Assert.assertEquals(ImportEnum.IMPORT_BAR, message.getRepeatedImportEnum(0));
+
+    Assert.assertEquals("224", message.getRepeatedStringPiece(0));
+    Assert.assertEquals("225", message.getRepeatedCord(0));
+
+    // Actually verify the second (modified) elements now.
+    Assert.assertEquals(501  , message.getRepeatedInt32   (1));
+    Assert.assertEquals(502L , message.getRepeatedInt64   (1));
+    Assert.assertEquals(503  , message.getRepeatedUint32  (1));
+    Assert.assertEquals(504L , message.getRepeatedUint64  (1));
+    Assert.assertEquals(505  , message.getRepeatedSint32  (1));
+    Assert.assertEquals(506L , message.getRepeatedSint64  (1));
+    Assert.assertEquals(507  , message.getRepeatedFixed32 (1));
+    Assert.assertEquals(508L , message.getRepeatedFixed64 (1));
+    Assert.assertEquals(509  , message.getRepeatedSfixed32(1));
+    Assert.assertEquals(510L , message.getRepeatedSfixed64(1));
+    Assert.assertEquals(511F , message.getRepeatedFloat   (1));
+    Assert.assertEquals(512D , message.getRepeatedDouble  (1));
+    Assert.assertEquals(true , message.getRepeatedBool    (1));
+    Assert.assertEquals("515", message.getRepeatedString  (1));
+    Assert.assertEquals(toBytes("516"), message.getRepeatedBytes(1));
+
+    Assert.assertEquals(517, message.getRepeatedGroup         (1).getA());
+    Assert.assertEquals(518, message.getRepeatedNestedMessage (1).getBb());
+    Assert.assertEquals(519, message.getRepeatedForeignMessage(1).getC());
+    Assert.assertEquals(520, message.getRepeatedImportMessage (1).getD());
+
+    Assert.assertEquals(TestAllTypes.NestedEnum.FOO, message.getRepeatedNestedEnum (1));
+    Assert.assertEquals(ForeignEnum.FOREIGN_FOO, message.getRepeatedForeignEnum(1));
+    Assert.assertEquals(ImportEnum.IMPORT_FOO, message.getRepeatedImportEnum(1));
+
+    Assert.assertEquals("524", message.getRepeatedStringPiece(1));
+    Assert.assertEquals("525", message.getRepeatedCord(1));
+  }
+
+  /**
+   * Set every field of {@code message} to a unique value.
+   */
+  public static void setPackedFields(TestPackedTypes.Builder message) {
+    message.addPackedInt32   (601);
+    message.addPackedInt64   (602);
+    message.addPackedUint32  (603);
+    message.addPackedUint64  (604);
+    message.addPackedSint32  (605);
+    message.addPackedSint64  (606);
+    message.addPackedFixed32 (607);
+    message.addPackedFixed64 (608);
+    message.addPackedSfixed32(609);
+    message.addPackedSfixed64(610);
+    message.addPackedFloat   (611);
+    message.addPackedDouble  (612);
+    message.addPackedBool    (true);
+    message.addPackedEnum    (ForeignEnum.FOREIGN_BAR);
+    // Add a second one of each field.
+    message.addPackedInt32   (701);
+    message.addPackedInt64   (702);
+    message.addPackedUint32  (703);
+    message.addPackedUint64  (704);
+    message.addPackedSint32  (705);
+    message.addPackedSint64  (706);
+    message.addPackedFixed32 (707);
+    message.addPackedFixed64 (708);
+    message.addPackedSfixed32(709);
+    message.addPackedSfixed64(710);
+    message.addPackedFloat   (711);
+    message.addPackedDouble  (712);
+    message.addPackedBool    (false);
+    message.addPackedEnum    (ForeignEnum.FOREIGN_BAZ);
+  }
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all fields of
+   * {@code message} are set to the values assigned by {@code setPackedFields}.
+   */
+  public static void assertPackedFieldsSet(TestPackedTypes message) {
+    Assert.assertEquals(2, message.getPackedInt32Count   ());
+    Assert.assertEquals(2, message.getPackedInt64Count   ());
+    Assert.assertEquals(2, message.getPackedUint32Count  ());
+    Assert.assertEquals(2, message.getPackedUint64Count  ());
+    Assert.assertEquals(2, message.getPackedSint32Count  ());
+    Assert.assertEquals(2, message.getPackedSint64Count  ());
+    Assert.assertEquals(2, message.getPackedFixed32Count ());
+    Assert.assertEquals(2, message.getPackedFixed64Count ());
+    Assert.assertEquals(2, message.getPackedSfixed32Count());
+    Assert.assertEquals(2, message.getPackedSfixed64Count());
+    Assert.assertEquals(2, message.getPackedFloatCount   ());
+    Assert.assertEquals(2, message.getPackedDoubleCount  ());
+    Assert.assertEquals(2, message.getPackedBoolCount    ());
+    Assert.assertEquals(2, message.getPackedEnumCount   ());
+    Assert.assertEquals(601  , message.getPackedInt32   (0));
+    Assert.assertEquals(602  , message.getPackedInt64   (0));
+    Assert.assertEquals(603  , message.getPackedUint32  (0));
+    Assert.assertEquals(604  , message.getPackedUint64  (0));
+    Assert.assertEquals(605  , message.getPackedSint32  (0));
+    Assert.assertEquals(606  , message.getPackedSint64  (0));
+    Assert.assertEquals(607  , message.getPackedFixed32 (0));
+    Assert.assertEquals(608  , message.getPackedFixed64 (0));
+    Assert.assertEquals(609  , message.getPackedSfixed32(0));
+    Assert.assertEquals(610  , message.getPackedSfixed64(0));
+    Assert.assertEquals(611  , message.getPackedFloat   (0), 0.0);
+    Assert.assertEquals(612  , message.getPackedDouble  (0), 0.0);
+    Assert.assertEquals(true , message.getPackedBool    (0));
+    Assert.assertEquals(ForeignEnum.FOREIGN_BAR, message.getPackedEnum(0));
+    Assert.assertEquals(701  , message.getPackedInt32   (1));
+    Assert.assertEquals(702  , message.getPackedInt64   (1));
+    Assert.assertEquals(703  , message.getPackedUint32  (1));
+    Assert.assertEquals(704  , message.getPackedUint64  (1));
+    Assert.assertEquals(705  , message.getPackedSint32  (1));
+    Assert.assertEquals(706  , message.getPackedSint64  (1));
+    Assert.assertEquals(707  , message.getPackedFixed32 (1));
+    Assert.assertEquals(708  , message.getPackedFixed64 (1));
+    Assert.assertEquals(709  , message.getPackedSfixed32(1));
+    Assert.assertEquals(710  , message.getPackedSfixed64(1));
+    Assert.assertEquals(711  , message.getPackedFloat   (1), 0.0);
+    Assert.assertEquals(712  , message.getPackedDouble  (1), 0.0);
+    Assert.assertEquals(false, message.getPackedBool    (1));
+    Assert.assertEquals(ForeignEnum.FOREIGN_BAZ, message.getPackedEnum(1));
+  }
+
+  // ===================================================================
+  // Like above, but for extensions
+
+  // Java gets confused with things like assertEquals(int, Integer):  it can't
+  // decide whether to call assertEquals(int, int) or assertEquals(Object,
+  // Object).  So we define these methods to help it.
+  private static void assertEqualsExactType(int a, int b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(long a, long b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(float a, float b) {
+    Assert.assertEquals(a, b, 0.0);
+  }
+  private static void assertEqualsExactType(double a, double b) {
+    Assert.assertEquals(a, b, 0.0);
+  }
+  private static void assertEqualsExactType(boolean a, boolean b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(String a, String b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(ByteString a, ByteString b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(TestAllTypes.NestedEnum a,
+                                            TestAllTypes.NestedEnum b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(ForeignEnum a, ForeignEnum b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(ImportEnum a, ImportEnum b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(TestAllTypesLite.NestedEnum a,
+                                            TestAllTypesLite.NestedEnum b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(ForeignEnumLite a,
+                                            ForeignEnumLite b) {
+    Assert.assertEquals(a, b);
+  }
+  private static void assertEqualsExactType(ImportEnumLite a,
+                                            ImportEnumLite b) {
+    Assert.assertEquals(a, b);
+  }
+
+  /**
+   * Get an unmodifiable {@link ExtensionRegistry} containing all the
+   * extensions of {@code TestAllExtensions}.
+   */
+  public static ExtensionRegistry getExtensionRegistry() {
+    ExtensionRegistry registry = ExtensionRegistry.newInstance();
+    registerAllExtensions(registry);
+    return registry.getUnmodifiable();
+  }
+
+  public static ExtensionRegistryLite getExtensionRegistryLite() {
+    ExtensionRegistryLite registry = ExtensionRegistryLite.newInstance();
+    registerAllExtensionsLite(registry);
+    return registry.getUnmodifiable();
+  }
+
+  /**
+   * Register all of {@code TestAllExtensions}'s extensions with the
+   * given {@link ExtensionRegistry}.
+   */
+  public static void registerAllExtensions(ExtensionRegistry registry) {
+    UnittestProto.registerAllExtensions(registry);
+    registerAllExtensionsLite(registry);
+  }
+
+  public static void registerAllExtensionsLite(ExtensionRegistryLite registry) {
+    UnittestLite.registerAllExtensions(registry);
+  }
+
+  /**
+   * Set every field of {@code message} to the values expected by
+   * {@code assertAllExtensionsSet()}.
+   */
+  public static void setAllExtensions(TestAllExtensions.Builder message) {
+    message.setExtension(optionalInt32Extension   , 101);
+    message.setExtension(optionalInt64Extension   , 102L);
+    message.setExtension(optionalUint32Extension  , 103);
+    message.setExtension(optionalUint64Extension  , 104L);
+    message.setExtension(optionalSint32Extension  , 105);
+    message.setExtension(optionalSint64Extension  , 106L);
+    message.setExtension(optionalFixed32Extension , 107);
+    message.setExtension(optionalFixed64Extension , 108L);
+    message.setExtension(optionalSfixed32Extension, 109);
+    message.setExtension(optionalSfixed64Extension, 110L);
+    message.setExtension(optionalFloatExtension   , 111F);
+    message.setExtension(optionalDoubleExtension  , 112D);
+    message.setExtension(optionalBoolExtension    , true);
+    message.setExtension(optionalStringExtension  , "115");
+    message.setExtension(optionalBytesExtension   , toBytes("116"));
+
+    message.setExtension(optionalGroupExtension,
+      OptionalGroup_extension.newBuilder().setA(117).build());
+    message.setExtension(optionalNestedMessageExtension,
+      TestAllTypes.NestedMessage.newBuilder().setBb(118).build());
+    message.setExtension(optionalForeignMessageExtension,
+      ForeignMessage.newBuilder().setC(119).build());
+    message.setExtension(optionalImportMessageExtension,
+      ImportMessage.newBuilder().setD(120).build());
+
+    message.setExtension(optionalNestedEnumExtension, TestAllTypes.NestedEnum.BAZ);
+    message.setExtension(optionalForeignEnumExtension, ForeignEnum.FOREIGN_BAZ);
+    message.setExtension(optionalImportEnumExtension, ImportEnum.IMPORT_BAZ);
+
+    message.setExtension(optionalStringPieceExtension, "124");
+    message.setExtension(optionalCordExtension, "125");
+
+    // -----------------------------------------------------------------
+
+    message.addExtension(repeatedInt32Extension   , 201);
+    message.addExtension(repeatedInt64Extension   , 202L);
+    message.addExtension(repeatedUint32Extension  , 203);
+    message.addExtension(repeatedUint64Extension  , 204L);
+    message.addExtension(repeatedSint32Extension  , 205);
+    message.addExtension(repeatedSint64Extension  , 206L);
+    message.addExtension(repeatedFixed32Extension , 207);
+    message.addExtension(repeatedFixed64Extension , 208L);
+    message.addExtension(repeatedSfixed32Extension, 209);
+    message.addExtension(repeatedSfixed64Extension, 210L);
+    message.addExtension(repeatedFloatExtension   , 211F);
+    message.addExtension(repeatedDoubleExtension  , 212D);
+    message.addExtension(repeatedBoolExtension    , true);
+    message.addExtension(repeatedStringExtension  , "215");
+    message.addExtension(repeatedBytesExtension   , toBytes("216"));
+
+    message.addExtension(repeatedGroupExtension,
+      RepeatedGroup_extension.newBuilder().setA(217).build());
+    message.addExtension(repeatedNestedMessageExtension,
+      TestAllTypes.NestedMessage.newBuilder().setBb(218).build());
+    message.addExtension(repeatedForeignMessageExtension,
+      ForeignMessage.newBuilder().setC(219).build());
+    message.addExtension(repeatedImportMessageExtension,
+      ImportMessage.newBuilder().setD(220).build());
+
+    message.addExtension(repeatedNestedEnumExtension, TestAllTypes.NestedEnum.BAR);
+    message.addExtension(repeatedForeignEnumExtension, ForeignEnum.FOREIGN_BAR);
+    message.addExtension(repeatedImportEnumExtension, ImportEnum.IMPORT_BAR);
+
+    message.addExtension(repeatedStringPieceExtension, "224");
+    message.addExtension(repeatedCordExtension, "225");
+
+    // Add a second one of each field.
+    message.addExtension(repeatedInt32Extension   , 301);
+    message.addExtension(repeatedInt64Extension   , 302L);
+    message.addExtension(repeatedUint32Extension  , 303);
+    message.addExtension(repeatedUint64Extension  , 304L);
+    message.addExtension(repeatedSint32Extension  , 305);
+    message.addExtension(repeatedSint64Extension  , 306L);
+    message.addExtension(repeatedFixed32Extension , 307);
+    message.addExtension(repeatedFixed64Extension , 308L);
+    message.addExtension(repeatedSfixed32Extension, 309);
+    message.addExtension(repeatedSfixed64Extension, 310L);
+    message.addExtension(repeatedFloatExtension   , 311F);
+    message.addExtension(repeatedDoubleExtension  , 312D);
+    message.addExtension(repeatedBoolExtension    , false);
+    message.addExtension(repeatedStringExtension  , "315");
+    message.addExtension(repeatedBytesExtension   , toBytes("316"));
+
+    message.addExtension(repeatedGroupExtension,
+      RepeatedGroup_extension.newBuilder().setA(317).build());
+    message.addExtension(repeatedNestedMessageExtension,
+      TestAllTypes.NestedMessage.newBuilder().setBb(318).build());
+    message.addExtension(repeatedForeignMessageExtension,
+      ForeignMessage.newBuilder().setC(319).build());
+    message.addExtension(repeatedImportMessageExtension,
+      ImportMessage.newBuilder().setD(320).build());
+
+    message.addExtension(repeatedNestedEnumExtension, TestAllTypes.NestedEnum.BAZ);
+    message.addExtension(repeatedForeignEnumExtension, ForeignEnum.FOREIGN_BAZ);
+    message.addExtension(repeatedImportEnumExtension, ImportEnum.IMPORT_BAZ);
+
+    message.addExtension(repeatedStringPieceExtension, "324");
+    message.addExtension(repeatedCordExtension, "325");
+
+    // -----------------------------------------------------------------
+
+    message.setExtension(defaultInt32Extension   , 401);
+    message.setExtension(defaultInt64Extension   , 402L);
+    message.setExtension(defaultUint32Extension  , 403);
+    message.setExtension(defaultUint64Extension  , 404L);
+    message.setExtension(defaultSint32Extension  , 405);
+    message.setExtension(defaultSint64Extension  , 406L);
+    message.setExtension(defaultFixed32Extension , 407);
+    message.setExtension(defaultFixed64Extension , 408L);
+    message.setExtension(defaultSfixed32Extension, 409);
+    message.setExtension(defaultSfixed64Extension, 410L);
+    message.setExtension(defaultFloatExtension   , 411F);
+    message.setExtension(defaultDoubleExtension  , 412D);
+    message.setExtension(defaultBoolExtension    , false);
+    message.setExtension(defaultStringExtension  , "415");
+    message.setExtension(defaultBytesExtension   , toBytes("416"));
+
+    message.setExtension(defaultNestedEnumExtension, TestAllTypes.NestedEnum.FOO);
+    message.setExtension(defaultForeignEnumExtension, ForeignEnum.FOREIGN_FOO);
+    message.setExtension(defaultImportEnumExtension, ImportEnum.IMPORT_FOO);
+
+    message.setExtension(defaultStringPieceExtension, "424");
+    message.setExtension(defaultCordExtension, "425");
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Modify the repeated extensions of {@code message} to contain the values
+   * expected by {@code assertRepeatedExtensionsModified()}.
+   */
+  public static void modifyRepeatedExtensions(
+      TestAllExtensions.Builder message) {
+    message.setExtension(repeatedInt32Extension   , 1, 501);
+    message.setExtension(repeatedInt64Extension   , 1, 502L);
+    message.setExtension(repeatedUint32Extension  , 1, 503);
+    message.setExtension(repeatedUint64Extension  , 1, 504L);
+    message.setExtension(repeatedSint32Extension  , 1, 505);
+    message.setExtension(repeatedSint64Extension  , 1, 506L);
+    message.setExtension(repeatedFixed32Extension , 1, 507);
+    message.setExtension(repeatedFixed64Extension , 1, 508L);
+    message.setExtension(repeatedSfixed32Extension, 1, 509);
+    message.setExtension(repeatedSfixed64Extension, 1, 510L);
+    message.setExtension(repeatedFloatExtension   , 1, 511F);
+    message.setExtension(repeatedDoubleExtension  , 1, 512D);
+    message.setExtension(repeatedBoolExtension    , 1, true);
+    message.setExtension(repeatedStringExtension  , 1, "515");
+    message.setExtension(repeatedBytesExtension   , 1, toBytes("516"));
+
+    message.setExtension(repeatedGroupExtension, 1,
+      RepeatedGroup_extension.newBuilder().setA(517).build());
+    message.setExtension(repeatedNestedMessageExtension, 1,
+      TestAllTypes.NestedMessage.newBuilder().setBb(518).build());
+    message.setExtension(repeatedForeignMessageExtension, 1,
+      ForeignMessage.newBuilder().setC(519).build());
+    message.setExtension(repeatedImportMessageExtension, 1,
+      ImportMessage.newBuilder().setD(520).build());
+
+    message.setExtension(repeatedNestedEnumExtension , 1, TestAllTypes.NestedEnum.FOO);
+    message.setExtension(repeatedForeignEnumExtension, 1, ForeignEnum.FOREIGN_FOO);
+    message.setExtension(repeatedImportEnumExtension , 1, ImportEnum.IMPORT_FOO);
+
+    message.setExtension(repeatedStringPieceExtension, 1, "524");
+    message.setExtension(repeatedCordExtension, 1, "525");
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all extensions of
+   * {@code message} are set to the values assigned by {@code setAllExtensions}.
+   */
+  public static void assertAllExtensionsSet(TestAllExtensions message) {
+    Assert.assertTrue(message.hasExtension(optionalInt32Extension   ));
+    Assert.assertTrue(message.hasExtension(optionalInt64Extension   ));
+    Assert.assertTrue(message.hasExtension(optionalUint32Extension  ));
+    Assert.assertTrue(message.hasExtension(optionalUint64Extension  ));
+    Assert.assertTrue(message.hasExtension(optionalSint32Extension  ));
+    Assert.assertTrue(message.hasExtension(optionalSint64Extension  ));
+    Assert.assertTrue(message.hasExtension(optionalFixed32Extension ));
+    Assert.assertTrue(message.hasExtension(optionalFixed64Extension ));
+    Assert.assertTrue(message.hasExtension(optionalSfixed32Extension));
+    Assert.assertTrue(message.hasExtension(optionalSfixed64Extension));
+    Assert.assertTrue(message.hasExtension(optionalFloatExtension   ));
+    Assert.assertTrue(message.hasExtension(optionalDoubleExtension  ));
+    Assert.assertTrue(message.hasExtension(optionalBoolExtension    ));
+    Assert.assertTrue(message.hasExtension(optionalStringExtension  ));
+    Assert.assertTrue(message.hasExtension(optionalBytesExtension   ));
+
+    Assert.assertTrue(message.hasExtension(optionalGroupExtension         ));
+    Assert.assertTrue(message.hasExtension(optionalNestedMessageExtension ));
+    Assert.assertTrue(message.hasExtension(optionalForeignMessageExtension));
+    Assert.assertTrue(message.hasExtension(optionalImportMessageExtension ));
+
+    Assert.assertTrue(message.getExtension(optionalGroupExtension         ).hasA());
+    Assert.assertTrue(message.getExtension(optionalNestedMessageExtension ).hasBb());
+    Assert.assertTrue(message.getExtension(optionalForeignMessageExtension).hasC());
+    Assert.assertTrue(message.getExtension(optionalImportMessageExtension ).hasD());
+
+    Assert.assertTrue(message.hasExtension(optionalNestedEnumExtension ));
+    Assert.assertTrue(message.hasExtension(optionalForeignEnumExtension));
+    Assert.assertTrue(message.hasExtension(optionalImportEnumExtension ));
+
+    Assert.assertTrue(message.hasExtension(optionalStringPieceExtension));
+    Assert.assertTrue(message.hasExtension(optionalCordExtension));
+
+    assertEqualsExactType(101  , message.getExtension(optionalInt32Extension   ));
+    assertEqualsExactType(102L , message.getExtension(optionalInt64Extension   ));
+    assertEqualsExactType(103  , message.getExtension(optionalUint32Extension  ));
+    assertEqualsExactType(104L , message.getExtension(optionalUint64Extension  ));
+    assertEqualsExactType(105  , message.getExtension(optionalSint32Extension  ));
+    assertEqualsExactType(106L , message.getExtension(optionalSint64Extension  ));
+    assertEqualsExactType(107  , message.getExtension(optionalFixed32Extension ));
+    assertEqualsExactType(108L , message.getExtension(optionalFixed64Extension ));
+    assertEqualsExactType(109  , message.getExtension(optionalSfixed32Extension));
+    assertEqualsExactType(110L , message.getExtension(optionalSfixed64Extension));
+    assertEqualsExactType(111F , message.getExtension(optionalFloatExtension   ));
+    assertEqualsExactType(112D , message.getExtension(optionalDoubleExtension  ));
+    assertEqualsExactType(true , message.getExtension(optionalBoolExtension    ));
+    assertEqualsExactType("115", message.getExtension(optionalStringExtension  ));
+    assertEqualsExactType(toBytes("116"), message.getExtension(optionalBytesExtension));
+
+    assertEqualsExactType(117, message.getExtension(optionalGroupExtension         ).getA());
+    assertEqualsExactType(118, message.getExtension(optionalNestedMessageExtension ).getBb());
+    assertEqualsExactType(119, message.getExtension(optionalForeignMessageExtension).getC());
+    assertEqualsExactType(120, message.getExtension(optionalImportMessageExtension ).getD());
+
+    assertEqualsExactType(TestAllTypes.NestedEnum.BAZ,
+      message.getExtension(optionalNestedEnumExtension));
+    assertEqualsExactType(ForeignEnum.FOREIGN_BAZ,
+      message.getExtension(optionalForeignEnumExtension));
+    assertEqualsExactType(ImportEnum.IMPORT_BAZ,
+      message.getExtension(optionalImportEnumExtension));
+
+    assertEqualsExactType("124", message.getExtension(optionalStringPieceExtension));
+    assertEqualsExactType("125", message.getExtension(optionalCordExtension));
+
+    // -----------------------------------------------------------------
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedInt32Extension   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedInt64Extension   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedUint32Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedUint64Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSint32Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSint64Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFixed32Extension ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFixed64Extension ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSfixed32Extension));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSfixed64Extension));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFloatExtension   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedDoubleExtension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedBoolExtension    ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedStringExtension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedBytesExtension   ));
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedGroupExtension         ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedNestedMessageExtension ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedForeignMessageExtension));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedImportMessageExtension ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedNestedEnumExtension    ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedForeignEnumExtension   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedImportEnumExtension    ));
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedStringPieceExtension));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedCordExtension));
+
+    assertEqualsExactType(201  , message.getExtension(repeatedInt32Extension   , 0));
+    assertEqualsExactType(202L , message.getExtension(repeatedInt64Extension   , 0));
+    assertEqualsExactType(203  , message.getExtension(repeatedUint32Extension  , 0));
+    assertEqualsExactType(204L , message.getExtension(repeatedUint64Extension  , 0));
+    assertEqualsExactType(205  , message.getExtension(repeatedSint32Extension  , 0));
+    assertEqualsExactType(206L , message.getExtension(repeatedSint64Extension  , 0));
+    assertEqualsExactType(207  , message.getExtension(repeatedFixed32Extension , 0));
+    assertEqualsExactType(208L , message.getExtension(repeatedFixed64Extension , 0));
+    assertEqualsExactType(209  , message.getExtension(repeatedSfixed32Extension, 0));
+    assertEqualsExactType(210L , message.getExtension(repeatedSfixed64Extension, 0));
+    assertEqualsExactType(211F , message.getExtension(repeatedFloatExtension   , 0));
+    assertEqualsExactType(212D , message.getExtension(repeatedDoubleExtension  , 0));
+    assertEqualsExactType(true , message.getExtension(repeatedBoolExtension    , 0));
+    assertEqualsExactType("215", message.getExtension(repeatedStringExtension  , 0));
+    assertEqualsExactType(toBytes("216"), message.getExtension(repeatedBytesExtension, 0));
+
+    assertEqualsExactType(217, message.getExtension(repeatedGroupExtension         , 0).getA());
+    assertEqualsExactType(218, message.getExtension(repeatedNestedMessageExtension , 0).getBb());
+    assertEqualsExactType(219, message.getExtension(repeatedForeignMessageExtension, 0).getC());
+    assertEqualsExactType(220, message.getExtension(repeatedImportMessageExtension , 0).getD());
+
+    assertEqualsExactType(TestAllTypes.NestedEnum.BAR,
+      message.getExtension(repeatedNestedEnumExtension, 0));
+    assertEqualsExactType(ForeignEnum.FOREIGN_BAR,
+      message.getExtension(repeatedForeignEnumExtension, 0));
+    assertEqualsExactType(ImportEnum.IMPORT_BAR,
+      message.getExtension(repeatedImportEnumExtension, 0));
+
+    assertEqualsExactType("224", message.getExtension(repeatedStringPieceExtension, 0));
+    assertEqualsExactType("225", message.getExtension(repeatedCordExtension, 0));
+
+    assertEqualsExactType(301  , message.getExtension(repeatedInt32Extension   , 1));
+    assertEqualsExactType(302L , message.getExtension(repeatedInt64Extension   , 1));
+    assertEqualsExactType(303  , message.getExtension(repeatedUint32Extension  , 1));
+    assertEqualsExactType(304L , message.getExtension(repeatedUint64Extension  , 1));
+    assertEqualsExactType(305  , message.getExtension(repeatedSint32Extension  , 1));
+    assertEqualsExactType(306L , message.getExtension(repeatedSint64Extension  , 1));
+    assertEqualsExactType(307  , message.getExtension(repeatedFixed32Extension , 1));
+    assertEqualsExactType(308L , message.getExtension(repeatedFixed64Extension , 1));
+    assertEqualsExactType(309  , message.getExtension(repeatedSfixed32Extension, 1));
+    assertEqualsExactType(310L , message.getExtension(repeatedSfixed64Extension, 1));
+    assertEqualsExactType(311F , message.getExtension(repeatedFloatExtension   , 1));
+    assertEqualsExactType(312D , message.getExtension(repeatedDoubleExtension  , 1));
+    assertEqualsExactType(false, message.getExtension(repeatedBoolExtension    , 1));
+    assertEqualsExactType("315", message.getExtension(repeatedStringExtension  , 1));
+    assertEqualsExactType(toBytes("316"), message.getExtension(repeatedBytesExtension, 1));
+
+    assertEqualsExactType(317, message.getExtension(repeatedGroupExtension         , 1).getA());
+    assertEqualsExactType(318, message.getExtension(repeatedNestedMessageExtension , 1).getBb());
+    assertEqualsExactType(319, message.getExtension(repeatedForeignMessageExtension, 1).getC());
+    assertEqualsExactType(320, message.getExtension(repeatedImportMessageExtension , 1).getD());
+
+    assertEqualsExactType(TestAllTypes.NestedEnum.BAZ,
+      message.getExtension(repeatedNestedEnumExtension, 1));
+    assertEqualsExactType(ForeignEnum.FOREIGN_BAZ,
+      message.getExtension(repeatedForeignEnumExtension, 1));
+    assertEqualsExactType(ImportEnum.IMPORT_BAZ,
+      message.getExtension(repeatedImportEnumExtension, 1));
+
+    assertEqualsExactType("324", message.getExtension(repeatedStringPieceExtension, 1));
+    assertEqualsExactType("325", message.getExtension(repeatedCordExtension, 1));
+
+    // -----------------------------------------------------------------
+
+    Assert.assertTrue(message.hasExtension(defaultInt32Extension   ));
+    Assert.assertTrue(message.hasExtension(defaultInt64Extension   ));
+    Assert.assertTrue(message.hasExtension(defaultUint32Extension  ));
+    Assert.assertTrue(message.hasExtension(defaultUint64Extension  ));
+    Assert.assertTrue(message.hasExtension(defaultSint32Extension  ));
+    Assert.assertTrue(message.hasExtension(defaultSint64Extension  ));
+    Assert.assertTrue(message.hasExtension(defaultFixed32Extension ));
+    Assert.assertTrue(message.hasExtension(defaultFixed64Extension ));
+    Assert.assertTrue(message.hasExtension(defaultSfixed32Extension));
+    Assert.assertTrue(message.hasExtension(defaultSfixed64Extension));
+    Assert.assertTrue(message.hasExtension(defaultFloatExtension   ));
+    Assert.assertTrue(message.hasExtension(defaultDoubleExtension  ));
+    Assert.assertTrue(message.hasExtension(defaultBoolExtension    ));
+    Assert.assertTrue(message.hasExtension(defaultStringExtension  ));
+    Assert.assertTrue(message.hasExtension(defaultBytesExtension   ));
+
+    Assert.assertTrue(message.hasExtension(defaultNestedEnumExtension ));
+    Assert.assertTrue(message.hasExtension(defaultForeignEnumExtension));
+    Assert.assertTrue(message.hasExtension(defaultImportEnumExtension ));
+
+    Assert.assertTrue(message.hasExtension(defaultStringPieceExtension));
+    Assert.assertTrue(message.hasExtension(defaultCordExtension));
+
+    assertEqualsExactType(401  , message.getExtension(defaultInt32Extension   ));
+    assertEqualsExactType(402L , message.getExtension(defaultInt64Extension   ));
+    assertEqualsExactType(403  , message.getExtension(defaultUint32Extension  ));
+    assertEqualsExactType(404L , message.getExtension(defaultUint64Extension  ));
+    assertEqualsExactType(405  , message.getExtension(defaultSint32Extension  ));
+    assertEqualsExactType(406L , message.getExtension(defaultSint64Extension  ));
+    assertEqualsExactType(407  , message.getExtension(defaultFixed32Extension ));
+    assertEqualsExactType(408L , message.getExtension(defaultFixed64Extension ));
+    assertEqualsExactType(409  , message.getExtension(defaultSfixed32Extension));
+    assertEqualsExactType(410L , message.getExtension(defaultSfixed64Extension));
+    assertEqualsExactType(411F , message.getExtension(defaultFloatExtension   ));
+    assertEqualsExactType(412D , message.getExtension(defaultDoubleExtension  ));
+    assertEqualsExactType(false, message.getExtension(defaultBoolExtension    ));
+    assertEqualsExactType("415", message.getExtension(defaultStringExtension  ));
+    assertEqualsExactType(toBytes("416"), message.getExtension(defaultBytesExtension));
+
+    assertEqualsExactType(TestAllTypes.NestedEnum.FOO,
+      message.getExtension(defaultNestedEnumExtension ));
+    assertEqualsExactType(ForeignEnum.FOREIGN_FOO,
+      message.getExtension(defaultForeignEnumExtension));
+    assertEqualsExactType(ImportEnum.IMPORT_FOO,
+      message.getExtension(defaultImportEnumExtension));
+
+    assertEqualsExactType("424", message.getExtension(defaultStringPieceExtension));
+    assertEqualsExactType("425", message.getExtension(defaultCordExtension));
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all extensions of
+   * {@code message} are cleared, and that getting the extensions returns their
+   * default values.
+   */
+  public static void assertExtensionsClear(TestAllExtensions message) {
+    // hasBlah() should initially be false for all optional fields.
+    Assert.assertFalse(message.hasExtension(optionalInt32Extension   ));
+    Assert.assertFalse(message.hasExtension(optionalInt64Extension   ));
+    Assert.assertFalse(message.hasExtension(optionalUint32Extension  ));
+    Assert.assertFalse(message.hasExtension(optionalUint64Extension  ));
+    Assert.assertFalse(message.hasExtension(optionalSint32Extension  ));
+    Assert.assertFalse(message.hasExtension(optionalSint64Extension  ));
+    Assert.assertFalse(message.hasExtension(optionalFixed32Extension ));
+    Assert.assertFalse(message.hasExtension(optionalFixed64Extension ));
+    Assert.assertFalse(message.hasExtension(optionalSfixed32Extension));
+    Assert.assertFalse(message.hasExtension(optionalSfixed64Extension));
+    Assert.assertFalse(message.hasExtension(optionalFloatExtension   ));
+    Assert.assertFalse(message.hasExtension(optionalDoubleExtension  ));
+    Assert.assertFalse(message.hasExtension(optionalBoolExtension    ));
+    Assert.assertFalse(message.hasExtension(optionalStringExtension  ));
+    Assert.assertFalse(message.hasExtension(optionalBytesExtension   ));
+
+    Assert.assertFalse(message.hasExtension(optionalGroupExtension         ));
+    Assert.assertFalse(message.hasExtension(optionalNestedMessageExtension ));
+    Assert.assertFalse(message.hasExtension(optionalForeignMessageExtension));
+    Assert.assertFalse(message.hasExtension(optionalImportMessageExtension ));
+
+    Assert.assertFalse(message.hasExtension(optionalNestedEnumExtension ));
+    Assert.assertFalse(message.hasExtension(optionalForeignEnumExtension));
+    Assert.assertFalse(message.hasExtension(optionalImportEnumExtension ));
+
+    Assert.assertFalse(message.hasExtension(optionalStringPieceExtension));
+    Assert.assertFalse(message.hasExtension(optionalCordExtension));
+
+    // Optional fields without defaults are set to zero or something like it.
+    assertEqualsExactType(0    , message.getExtension(optionalInt32Extension   ));
+    assertEqualsExactType(0L   , message.getExtension(optionalInt64Extension   ));
+    assertEqualsExactType(0    , message.getExtension(optionalUint32Extension  ));
+    assertEqualsExactType(0L   , message.getExtension(optionalUint64Extension  ));
+    assertEqualsExactType(0    , message.getExtension(optionalSint32Extension  ));
+    assertEqualsExactType(0L   , message.getExtension(optionalSint64Extension  ));
+    assertEqualsExactType(0    , message.getExtension(optionalFixed32Extension ));
+    assertEqualsExactType(0L   , message.getExtension(optionalFixed64Extension ));
+    assertEqualsExactType(0    , message.getExtension(optionalSfixed32Extension));
+    assertEqualsExactType(0L   , message.getExtension(optionalSfixed64Extension));
+    assertEqualsExactType(0F   , message.getExtension(optionalFloatExtension   ));
+    assertEqualsExactType(0D   , message.getExtension(optionalDoubleExtension  ));
+    assertEqualsExactType(false, message.getExtension(optionalBoolExtension    ));
+    assertEqualsExactType(""   , message.getExtension(optionalStringExtension  ));
+    assertEqualsExactType(ByteString.EMPTY, message.getExtension(optionalBytesExtension));
+
+    // Embedded messages should also be clear.
+    Assert.assertFalse(message.getExtension(optionalGroupExtension         ).hasA());
+    Assert.assertFalse(message.getExtension(optionalNestedMessageExtension ).hasBb());
+    Assert.assertFalse(message.getExtension(optionalForeignMessageExtension).hasC());
+    Assert.assertFalse(message.getExtension(optionalImportMessageExtension ).hasD());
+
+    assertEqualsExactType(0, message.getExtension(optionalGroupExtension         ).getA());
+    assertEqualsExactType(0, message.getExtension(optionalNestedMessageExtension ).getBb());
+    assertEqualsExactType(0, message.getExtension(optionalForeignMessageExtension).getC());
+    assertEqualsExactType(0, message.getExtension(optionalImportMessageExtension ).getD());
+
+    // Enums without defaults are set to the first value in the enum.
+    assertEqualsExactType(TestAllTypes.NestedEnum.FOO,
+      message.getExtension(optionalNestedEnumExtension ));
+    assertEqualsExactType(ForeignEnum.FOREIGN_FOO,
+      message.getExtension(optionalForeignEnumExtension));
+    assertEqualsExactType(ImportEnum.IMPORT_FOO,
+      message.getExtension(optionalImportEnumExtension));
+
+    assertEqualsExactType("", message.getExtension(optionalStringPieceExtension));
+    assertEqualsExactType("", message.getExtension(optionalCordExtension));
+
+    // Repeated fields are empty.
+    Assert.assertEquals(0, message.getExtensionCount(repeatedInt32Extension   ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedInt64Extension   ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedUint32Extension  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedUint64Extension  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedSint32Extension  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedSint64Extension  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedFixed32Extension ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedFixed64Extension ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedSfixed32Extension));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedSfixed64Extension));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedFloatExtension   ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedDoubleExtension  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedBoolExtension    ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedStringExtension  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedBytesExtension   ));
+
+    Assert.assertEquals(0, message.getExtensionCount(repeatedGroupExtension         ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedNestedMessageExtension ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedForeignMessageExtension));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedImportMessageExtension ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedNestedEnumExtension    ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedForeignEnumExtension   ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedImportEnumExtension    ));
+
+    Assert.assertEquals(0, message.getExtensionCount(repeatedStringPieceExtension));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedCordExtension));
+
+    // hasBlah() should also be false for all default fields.
+    Assert.assertFalse(message.hasExtension(defaultInt32Extension   ));
+    Assert.assertFalse(message.hasExtension(defaultInt64Extension   ));
+    Assert.assertFalse(message.hasExtension(defaultUint32Extension  ));
+    Assert.assertFalse(message.hasExtension(defaultUint64Extension  ));
+    Assert.assertFalse(message.hasExtension(defaultSint32Extension  ));
+    Assert.assertFalse(message.hasExtension(defaultSint64Extension  ));
+    Assert.assertFalse(message.hasExtension(defaultFixed32Extension ));
+    Assert.assertFalse(message.hasExtension(defaultFixed64Extension ));
+    Assert.assertFalse(message.hasExtension(defaultSfixed32Extension));
+    Assert.assertFalse(message.hasExtension(defaultSfixed64Extension));
+    Assert.assertFalse(message.hasExtension(defaultFloatExtension   ));
+    Assert.assertFalse(message.hasExtension(defaultDoubleExtension  ));
+    Assert.assertFalse(message.hasExtension(defaultBoolExtension    ));
+    Assert.assertFalse(message.hasExtension(defaultStringExtension  ));
+    Assert.assertFalse(message.hasExtension(defaultBytesExtension   ));
+
+    Assert.assertFalse(message.hasExtension(defaultNestedEnumExtension ));
+    Assert.assertFalse(message.hasExtension(defaultForeignEnumExtension));
+    Assert.assertFalse(message.hasExtension(defaultImportEnumExtension ));
+
+    Assert.assertFalse(message.hasExtension(defaultStringPieceExtension));
+    Assert.assertFalse(message.hasExtension(defaultCordExtension));
+
+    // Fields with defaults have their default values (duh).
+    assertEqualsExactType( 41    , message.getExtension(defaultInt32Extension   ));
+    assertEqualsExactType( 42L   , message.getExtension(defaultInt64Extension   ));
+    assertEqualsExactType( 43    , message.getExtension(defaultUint32Extension  ));
+    assertEqualsExactType( 44L   , message.getExtension(defaultUint64Extension  ));
+    assertEqualsExactType(-45    , message.getExtension(defaultSint32Extension  ));
+    assertEqualsExactType( 46L   , message.getExtension(defaultSint64Extension  ));
+    assertEqualsExactType( 47    , message.getExtension(defaultFixed32Extension ));
+    assertEqualsExactType( 48L   , message.getExtension(defaultFixed64Extension ));
+    assertEqualsExactType( 49    , message.getExtension(defaultSfixed32Extension));
+    assertEqualsExactType(-50L   , message.getExtension(defaultSfixed64Extension));
+    assertEqualsExactType( 51.5F , message.getExtension(defaultFloatExtension   ));
+    assertEqualsExactType( 52e3D , message.getExtension(defaultDoubleExtension  ));
+    assertEqualsExactType(true   , message.getExtension(defaultBoolExtension    ));
+    assertEqualsExactType("hello", message.getExtension(defaultStringExtension  ));
+    assertEqualsExactType(toBytes("world"), message.getExtension(defaultBytesExtension));
+
+    assertEqualsExactType(TestAllTypes.NestedEnum.BAR,
+      message.getExtension(defaultNestedEnumExtension ));
+    assertEqualsExactType(ForeignEnum.FOREIGN_BAR,
+      message.getExtension(defaultForeignEnumExtension));
+    assertEqualsExactType(ImportEnum.IMPORT_BAR,
+      message.getExtension(defaultImportEnumExtension));
+
+    assertEqualsExactType("abc", message.getExtension(defaultStringPieceExtension));
+    assertEqualsExactType("123", message.getExtension(defaultCordExtension));
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all extensions of
+   * {@code message} are set to the values assigned by {@code setAllExtensions}
+   * followed by {@code modifyRepeatedExtensions}.
+   */
+  public static void assertRepeatedExtensionsModified(
+      TestAllExtensions message) {
+    // ModifyRepeatedFields only sets the second repeated element of each
+    // field.  In addition to verifying this, we also verify that the first
+    // element and size were *not* modified.
+    Assert.assertEquals(2, message.getExtensionCount(repeatedInt32Extension   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedInt64Extension   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedUint32Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedUint64Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSint32Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSint64Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFixed32Extension ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFixed64Extension ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSfixed32Extension));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSfixed64Extension));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFloatExtension   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedDoubleExtension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedBoolExtension    ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedStringExtension  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedBytesExtension   ));
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedGroupExtension         ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedNestedMessageExtension ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedForeignMessageExtension));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedImportMessageExtension ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedNestedEnumExtension    ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedForeignEnumExtension   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedImportEnumExtension    ));
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedStringPieceExtension));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedCordExtension));
+
+    assertEqualsExactType(201  , message.getExtension(repeatedInt32Extension   , 0));
+    assertEqualsExactType(202L , message.getExtension(repeatedInt64Extension   , 0));
+    assertEqualsExactType(203  , message.getExtension(repeatedUint32Extension  , 0));
+    assertEqualsExactType(204L , message.getExtension(repeatedUint64Extension  , 0));
+    assertEqualsExactType(205  , message.getExtension(repeatedSint32Extension  , 0));
+    assertEqualsExactType(206L , message.getExtension(repeatedSint64Extension  , 0));
+    assertEqualsExactType(207  , message.getExtension(repeatedFixed32Extension , 0));
+    assertEqualsExactType(208L , message.getExtension(repeatedFixed64Extension , 0));
+    assertEqualsExactType(209  , message.getExtension(repeatedSfixed32Extension, 0));
+    assertEqualsExactType(210L , message.getExtension(repeatedSfixed64Extension, 0));
+    assertEqualsExactType(211F , message.getExtension(repeatedFloatExtension   , 0));
+    assertEqualsExactType(212D , message.getExtension(repeatedDoubleExtension  , 0));
+    assertEqualsExactType(true , message.getExtension(repeatedBoolExtension    , 0));
+    assertEqualsExactType("215", message.getExtension(repeatedStringExtension  , 0));
+    assertEqualsExactType(toBytes("216"), message.getExtension(repeatedBytesExtension, 0));
+
+    assertEqualsExactType(217, message.getExtension(repeatedGroupExtension         , 0).getA());
+    assertEqualsExactType(218, message.getExtension(repeatedNestedMessageExtension , 0).getBb());
+    assertEqualsExactType(219, message.getExtension(repeatedForeignMessageExtension, 0).getC());
+    assertEqualsExactType(220, message.getExtension(repeatedImportMessageExtension , 0).getD());
+
+    assertEqualsExactType(TestAllTypes.NestedEnum.BAR,
+      message.getExtension(repeatedNestedEnumExtension, 0));
+    assertEqualsExactType(ForeignEnum.FOREIGN_BAR,
+      message.getExtension(repeatedForeignEnumExtension, 0));
+    assertEqualsExactType(ImportEnum.IMPORT_BAR,
+      message.getExtension(repeatedImportEnumExtension, 0));
+
+    assertEqualsExactType("224", message.getExtension(repeatedStringPieceExtension, 0));
+    assertEqualsExactType("225", message.getExtension(repeatedCordExtension, 0));
+
+    // Actually verify the second (modified) elements now.
+    assertEqualsExactType(501  , message.getExtension(repeatedInt32Extension   , 1));
+    assertEqualsExactType(502L , message.getExtension(repeatedInt64Extension   , 1));
+    assertEqualsExactType(503  , message.getExtension(repeatedUint32Extension  , 1));
+    assertEqualsExactType(504L , message.getExtension(repeatedUint64Extension  , 1));
+    assertEqualsExactType(505  , message.getExtension(repeatedSint32Extension  , 1));
+    assertEqualsExactType(506L , message.getExtension(repeatedSint64Extension  , 1));
+    assertEqualsExactType(507  , message.getExtension(repeatedFixed32Extension , 1));
+    assertEqualsExactType(508L , message.getExtension(repeatedFixed64Extension , 1));
+    assertEqualsExactType(509  , message.getExtension(repeatedSfixed32Extension, 1));
+    assertEqualsExactType(510L , message.getExtension(repeatedSfixed64Extension, 1));
+    assertEqualsExactType(511F , message.getExtension(repeatedFloatExtension   , 1));
+    assertEqualsExactType(512D , message.getExtension(repeatedDoubleExtension  , 1));
+    assertEqualsExactType(true , message.getExtension(repeatedBoolExtension    , 1));
+    assertEqualsExactType("515", message.getExtension(repeatedStringExtension  , 1));
+    assertEqualsExactType(toBytes("516"), message.getExtension(repeatedBytesExtension, 1));
+
+    assertEqualsExactType(517, message.getExtension(repeatedGroupExtension         , 1).getA());
+    assertEqualsExactType(518, message.getExtension(repeatedNestedMessageExtension , 1).getBb());
+    assertEqualsExactType(519, message.getExtension(repeatedForeignMessageExtension, 1).getC());
+    assertEqualsExactType(520, message.getExtension(repeatedImportMessageExtension , 1).getD());
+
+    assertEqualsExactType(TestAllTypes.NestedEnum.FOO,
+      message.getExtension(repeatedNestedEnumExtension, 1));
+    assertEqualsExactType(ForeignEnum.FOREIGN_FOO,
+      message.getExtension(repeatedForeignEnumExtension, 1));
+    assertEqualsExactType(ImportEnum.IMPORT_FOO,
+      message.getExtension(repeatedImportEnumExtension, 1));
+
+    assertEqualsExactType("524", message.getExtension(repeatedStringPieceExtension, 1));
+    assertEqualsExactType("525", message.getExtension(repeatedCordExtension, 1));
+  }
+
+  public static void setPackedExtensions(TestPackedExtensions.Builder message) {
+    message.addExtension(packedInt32Extension   , 601);
+    message.addExtension(packedInt64Extension   , 602L);
+    message.addExtension(packedUint32Extension  , 603);
+    message.addExtension(packedUint64Extension  , 604L);
+    message.addExtension(packedSint32Extension  , 605);
+    message.addExtension(packedSint64Extension  , 606L);
+    message.addExtension(packedFixed32Extension , 607);
+    message.addExtension(packedFixed64Extension , 608L);
+    message.addExtension(packedSfixed32Extension, 609);
+    message.addExtension(packedSfixed64Extension, 610L);
+    message.addExtension(packedFloatExtension   , 611F);
+    message.addExtension(packedDoubleExtension  , 612D);
+    message.addExtension(packedBoolExtension    , true);
+    message.addExtension(packedEnumExtension, ForeignEnum.FOREIGN_BAR);
+    // Add a second one of each field.
+    message.addExtension(packedInt32Extension   , 701);
+    message.addExtension(packedInt64Extension   , 702L);
+    message.addExtension(packedUint32Extension  , 703);
+    message.addExtension(packedUint64Extension  , 704L);
+    message.addExtension(packedSint32Extension  , 705);
+    message.addExtension(packedSint64Extension  , 706L);
+    message.addExtension(packedFixed32Extension , 707);
+    message.addExtension(packedFixed64Extension , 708L);
+    message.addExtension(packedSfixed32Extension, 709);
+    message.addExtension(packedSfixed64Extension, 710L);
+    message.addExtension(packedFloatExtension   , 711F);
+    message.addExtension(packedDoubleExtension  , 712D);
+    message.addExtension(packedBoolExtension    , false);
+    message.addExtension(packedEnumExtension, ForeignEnum.FOREIGN_BAZ);
+  }
+
+  public static void assertPackedExtensionsSet(TestPackedExtensions message) {
+    Assert.assertEquals(2, message.getExtensionCount(packedInt32Extension   ));
+    Assert.assertEquals(2, message.getExtensionCount(packedInt64Extension   ));
+    Assert.assertEquals(2, message.getExtensionCount(packedUint32Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedUint64Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedSint32Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedSint64Extension  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedFixed32Extension ));
+    Assert.assertEquals(2, message.getExtensionCount(packedFixed64Extension ));
+    Assert.assertEquals(2, message.getExtensionCount(packedSfixed32Extension));
+    Assert.assertEquals(2, message.getExtensionCount(packedSfixed64Extension));
+    Assert.assertEquals(2, message.getExtensionCount(packedFloatExtension   ));
+    Assert.assertEquals(2, message.getExtensionCount(packedDoubleExtension  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedBoolExtension    ));
+    Assert.assertEquals(2, message.getExtensionCount(packedEnumExtension));
+    assertEqualsExactType(601  , message.getExtension(packedInt32Extension   , 0));
+    assertEqualsExactType(602L , message.getExtension(packedInt64Extension   , 0));
+    assertEqualsExactType(603  , message.getExtension(packedUint32Extension  , 0));
+    assertEqualsExactType(604L , message.getExtension(packedUint64Extension  , 0));
+    assertEqualsExactType(605  , message.getExtension(packedSint32Extension  , 0));
+    assertEqualsExactType(606L , message.getExtension(packedSint64Extension  , 0));
+    assertEqualsExactType(607  , message.getExtension(packedFixed32Extension , 0));
+    assertEqualsExactType(608L , message.getExtension(packedFixed64Extension , 0));
+    assertEqualsExactType(609  , message.getExtension(packedSfixed32Extension, 0));
+    assertEqualsExactType(610L , message.getExtension(packedSfixed64Extension, 0));
+    assertEqualsExactType(611F , message.getExtension(packedFloatExtension   , 0));
+    assertEqualsExactType(612D , message.getExtension(packedDoubleExtension  , 0));
+    assertEqualsExactType(true , message.getExtension(packedBoolExtension    , 0));
+    assertEqualsExactType(ForeignEnum.FOREIGN_BAR,
+                          message.getExtension(packedEnumExtension, 0));
+    assertEqualsExactType(701  , message.getExtension(packedInt32Extension   , 1));
+    assertEqualsExactType(702L , message.getExtension(packedInt64Extension   , 1));
+    assertEqualsExactType(703  , message.getExtension(packedUint32Extension  , 1));
+    assertEqualsExactType(704L , message.getExtension(packedUint64Extension  , 1));
+    assertEqualsExactType(705  , message.getExtension(packedSint32Extension  , 1));
+    assertEqualsExactType(706L , message.getExtension(packedSint64Extension  , 1));
+    assertEqualsExactType(707  , message.getExtension(packedFixed32Extension , 1));
+    assertEqualsExactType(708L , message.getExtension(packedFixed64Extension , 1));
+    assertEqualsExactType(709  , message.getExtension(packedSfixed32Extension, 1));
+    assertEqualsExactType(710L , message.getExtension(packedSfixed64Extension, 1));
+    assertEqualsExactType(711F , message.getExtension(packedFloatExtension   , 1));
+    assertEqualsExactType(712D , message.getExtension(packedDoubleExtension  , 1));
+    assertEqualsExactType(false, message.getExtension(packedBoolExtension    , 1));
+    assertEqualsExactType(ForeignEnum.FOREIGN_BAZ,
+                          message.getExtension(packedEnumExtension, 1));
+  }
+
+  // ===================================================================
+  // Lite extensions
+
+  /**
+   * Set every field of {@code message} to the values expected by
+   * {@code assertAllExtensionsSet()}.
+   */
+  public static void setAllExtensions(TestAllExtensionsLite.Builder message) {
+    message.setExtension(optionalInt32ExtensionLite   , 101);
+    message.setExtension(optionalInt64ExtensionLite   , 102L);
+    message.setExtension(optionalUint32ExtensionLite  , 103);
+    message.setExtension(optionalUint64ExtensionLite  , 104L);
+    message.setExtension(optionalSint32ExtensionLite  , 105);
+    message.setExtension(optionalSint64ExtensionLite  , 106L);
+    message.setExtension(optionalFixed32ExtensionLite , 107);
+    message.setExtension(optionalFixed64ExtensionLite , 108L);
+    message.setExtension(optionalSfixed32ExtensionLite, 109);
+    message.setExtension(optionalSfixed64ExtensionLite, 110L);
+    message.setExtension(optionalFloatExtensionLite   , 111F);
+    message.setExtension(optionalDoubleExtensionLite  , 112D);
+    message.setExtension(optionalBoolExtensionLite    , true);
+    message.setExtension(optionalStringExtensionLite  , "115");
+    message.setExtension(optionalBytesExtensionLite   , toBytes("116"));
+
+    message.setExtension(optionalGroupExtensionLite,
+      OptionalGroup_extension_lite.newBuilder().setA(117).build());
+    message.setExtension(optionalNestedMessageExtensionLite,
+      TestAllTypesLite.NestedMessage.newBuilder().setBb(118).build());
+    message.setExtension(optionalForeignMessageExtensionLite,
+      ForeignMessageLite.newBuilder().setC(119).build());
+    message.setExtension(optionalImportMessageExtensionLite,
+      ImportMessageLite.newBuilder().setD(120).build());
+
+    message.setExtension(optionalNestedEnumExtensionLite, TestAllTypesLite.NestedEnum.BAZ);
+    message.setExtension(optionalForeignEnumExtensionLite, ForeignEnumLite.FOREIGN_LITE_BAZ);
+    message.setExtension(optionalImportEnumExtensionLite, ImportEnumLite.IMPORT_LITE_BAZ);
+
+    message.setExtension(optionalStringPieceExtensionLite, "124");
+    message.setExtension(optionalCordExtensionLite, "125");
+
+    // -----------------------------------------------------------------
+
+    message.addExtension(repeatedInt32ExtensionLite   , 201);
+    message.addExtension(repeatedInt64ExtensionLite   , 202L);
+    message.addExtension(repeatedUint32ExtensionLite  , 203);
+    message.addExtension(repeatedUint64ExtensionLite  , 204L);
+    message.addExtension(repeatedSint32ExtensionLite  , 205);
+    message.addExtension(repeatedSint64ExtensionLite  , 206L);
+    message.addExtension(repeatedFixed32ExtensionLite , 207);
+    message.addExtension(repeatedFixed64ExtensionLite , 208L);
+    message.addExtension(repeatedSfixed32ExtensionLite, 209);
+    message.addExtension(repeatedSfixed64ExtensionLite, 210L);
+    message.addExtension(repeatedFloatExtensionLite   , 211F);
+    message.addExtension(repeatedDoubleExtensionLite  , 212D);
+    message.addExtension(repeatedBoolExtensionLite    , true);
+    message.addExtension(repeatedStringExtensionLite  , "215");
+    message.addExtension(repeatedBytesExtensionLite   , toBytes("216"));
+
+    message.addExtension(repeatedGroupExtensionLite,
+      RepeatedGroup_extension_lite.newBuilder().setA(217).build());
+    message.addExtension(repeatedNestedMessageExtensionLite,
+      TestAllTypesLite.NestedMessage.newBuilder().setBb(218).build());
+    message.addExtension(repeatedForeignMessageExtensionLite,
+      ForeignMessageLite.newBuilder().setC(219).build());
+    message.addExtension(repeatedImportMessageExtensionLite,
+      ImportMessageLite.newBuilder().setD(220).build());
+
+    message.addExtension(repeatedNestedEnumExtensionLite, TestAllTypesLite.NestedEnum.BAR);
+    message.addExtension(repeatedForeignEnumExtensionLite, ForeignEnumLite.FOREIGN_LITE_BAR);
+    message.addExtension(repeatedImportEnumExtensionLite, ImportEnumLite.IMPORT_LITE_BAR);
+
+    message.addExtension(repeatedStringPieceExtensionLite, "224");
+    message.addExtension(repeatedCordExtensionLite, "225");
+
+    // Add a second one of each field.
+    message.addExtension(repeatedInt32ExtensionLite   , 301);
+    message.addExtension(repeatedInt64ExtensionLite   , 302L);
+    message.addExtension(repeatedUint32ExtensionLite  , 303);
+    message.addExtension(repeatedUint64ExtensionLite  , 304L);
+    message.addExtension(repeatedSint32ExtensionLite  , 305);
+    message.addExtension(repeatedSint64ExtensionLite  , 306L);
+    message.addExtension(repeatedFixed32ExtensionLite , 307);
+    message.addExtension(repeatedFixed64ExtensionLite , 308L);
+    message.addExtension(repeatedSfixed32ExtensionLite, 309);
+    message.addExtension(repeatedSfixed64ExtensionLite, 310L);
+    message.addExtension(repeatedFloatExtensionLite   , 311F);
+    message.addExtension(repeatedDoubleExtensionLite  , 312D);
+    message.addExtension(repeatedBoolExtensionLite    , false);
+    message.addExtension(repeatedStringExtensionLite  , "315");
+    message.addExtension(repeatedBytesExtensionLite   , toBytes("316"));
+
+    message.addExtension(repeatedGroupExtensionLite,
+      RepeatedGroup_extension_lite.newBuilder().setA(317).build());
+    message.addExtension(repeatedNestedMessageExtensionLite,
+      TestAllTypesLite.NestedMessage.newBuilder().setBb(318).build());
+    message.addExtension(repeatedForeignMessageExtensionLite,
+      ForeignMessageLite.newBuilder().setC(319).build());
+    message.addExtension(repeatedImportMessageExtensionLite,
+      ImportMessageLite.newBuilder().setD(320).build());
+
+    message.addExtension(repeatedNestedEnumExtensionLite, TestAllTypesLite.NestedEnum.BAZ);
+    message.addExtension(repeatedForeignEnumExtensionLite, ForeignEnumLite.FOREIGN_LITE_BAZ);
+    message.addExtension(repeatedImportEnumExtensionLite, ImportEnumLite.IMPORT_LITE_BAZ);
+
+    message.addExtension(repeatedStringPieceExtensionLite, "324");
+    message.addExtension(repeatedCordExtensionLite, "325");
+
+    // -----------------------------------------------------------------
+
+    message.setExtension(defaultInt32ExtensionLite   , 401);
+    message.setExtension(defaultInt64ExtensionLite   , 402L);
+    message.setExtension(defaultUint32ExtensionLite  , 403);
+    message.setExtension(defaultUint64ExtensionLite  , 404L);
+    message.setExtension(defaultSint32ExtensionLite  , 405);
+    message.setExtension(defaultSint64ExtensionLite  , 406L);
+    message.setExtension(defaultFixed32ExtensionLite , 407);
+    message.setExtension(defaultFixed64ExtensionLite , 408L);
+    message.setExtension(defaultSfixed32ExtensionLite, 409);
+    message.setExtension(defaultSfixed64ExtensionLite, 410L);
+    message.setExtension(defaultFloatExtensionLite   , 411F);
+    message.setExtension(defaultDoubleExtensionLite  , 412D);
+    message.setExtension(defaultBoolExtensionLite    , false);
+    message.setExtension(defaultStringExtensionLite  , "415");
+    message.setExtension(defaultBytesExtensionLite   , toBytes("416"));
+
+    message.setExtension(defaultNestedEnumExtensionLite, TestAllTypesLite.NestedEnum.FOO);
+    message.setExtension(defaultForeignEnumExtensionLite, ForeignEnumLite.FOREIGN_LITE_FOO);
+    message.setExtension(defaultImportEnumExtensionLite, ImportEnumLite.IMPORT_LITE_FOO);
+
+    message.setExtension(defaultStringPieceExtensionLite, "424");
+    message.setExtension(defaultCordExtensionLite, "425");
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Modify the repeated extensions of {@code message} to contain the values
+   * expected by {@code assertRepeatedExtensionsModified()}.
+   */
+  public static void modifyRepeatedExtensions(
+      TestAllExtensionsLite.Builder message) {
+    message.setExtension(repeatedInt32ExtensionLite   , 1, 501);
+    message.setExtension(repeatedInt64ExtensionLite   , 1, 502L);
+    message.setExtension(repeatedUint32ExtensionLite  , 1, 503);
+    message.setExtension(repeatedUint64ExtensionLite  , 1, 504L);
+    message.setExtension(repeatedSint32ExtensionLite  , 1, 505);
+    message.setExtension(repeatedSint64ExtensionLite  , 1, 506L);
+    message.setExtension(repeatedFixed32ExtensionLite , 1, 507);
+    message.setExtension(repeatedFixed64ExtensionLite , 1, 508L);
+    message.setExtension(repeatedSfixed32ExtensionLite, 1, 509);
+    message.setExtension(repeatedSfixed64ExtensionLite, 1, 510L);
+    message.setExtension(repeatedFloatExtensionLite   , 1, 511F);
+    message.setExtension(repeatedDoubleExtensionLite  , 1, 512D);
+    message.setExtension(repeatedBoolExtensionLite    , 1, true);
+    message.setExtension(repeatedStringExtensionLite  , 1, "515");
+    message.setExtension(repeatedBytesExtensionLite   , 1, toBytes("516"));
+
+    message.setExtension(repeatedGroupExtensionLite, 1,
+      RepeatedGroup_extension_lite.newBuilder().setA(517).build());
+    message.setExtension(repeatedNestedMessageExtensionLite, 1,
+      TestAllTypesLite.NestedMessage.newBuilder().setBb(518).build());
+    message.setExtension(repeatedForeignMessageExtensionLite, 1,
+      ForeignMessageLite.newBuilder().setC(519).build());
+    message.setExtension(repeatedImportMessageExtensionLite, 1,
+      ImportMessageLite.newBuilder().setD(520).build());
+
+    message.setExtension(repeatedNestedEnumExtensionLite , 1, TestAllTypesLite.NestedEnum.FOO);
+    message.setExtension(repeatedForeignEnumExtensionLite, 1, ForeignEnumLite.FOREIGN_LITE_FOO);
+    message.setExtension(repeatedImportEnumExtensionLite , 1, ImportEnumLite.IMPORT_LITE_FOO);
+
+    message.setExtension(repeatedStringPieceExtensionLite, 1, "524");
+    message.setExtension(repeatedCordExtensionLite, 1, "525");
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all extensions of
+   * {@code message} are set to the values assigned by {@code setAllExtensions}.
+   */
+  public static void assertAllExtensionsSet(TestAllExtensionsLite message) {
+    Assert.assertTrue(message.hasExtension(optionalInt32ExtensionLite   ));
+    Assert.assertTrue(message.hasExtension(optionalInt64ExtensionLite   ));
+    Assert.assertTrue(message.hasExtension(optionalUint32ExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(optionalUint64ExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(optionalSint32ExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(optionalSint64ExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(optionalFixed32ExtensionLite ));
+    Assert.assertTrue(message.hasExtension(optionalFixed64ExtensionLite ));
+    Assert.assertTrue(message.hasExtension(optionalSfixed32ExtensionLite));
+    Assert.assertTrue(message.hasExtension(optionalSfixed64ExtensionLite));
+    Assert.assertTrue(message.hasExtension(optionalFloatExtensionLite   ));
+    Assert.assertTrue(message.hasExtension(optionalDoubleExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(optionalBoolExtensionLite    ));
+    Assert.assertTrue(message.hasExtension(optionalStringExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(optionalBytesExtensionLite   ));
+
+    Assert.assertTrue(message.hasExtension(optionalGroupExtensionLite         ));
+    Assert.assertTrue(message.hasExtension(optionalNestedMessageExtensionLite ));
+    Assert.assertTrue(message.hasExtension(optionalForeignMessageExtensionLite));
+    Assert.assertTrue(message.hasExtension(optionalImportMessageExtensionLite ));
+
+    Assert.assertTrue(message.getExtension(optionalGroupExtensionLite         ).hasA());
+    Assert.assertTrue(message.getExtension(optionalNestedMessageExtensionLite ).hasBb());
+    Assert.assertTrue(message.getExtension(optionalForeignMessageExtensionLite).hasC());
+    Assert.assertTrue(message.getExtension(optionalImportMessageExtensionLite ).hasD());
+
+    Assert.assertTrue(message.hasExtension(optionalNestedEnumExtensionLite ));
+    Assert.assertTrue(message.hasExtension(optionalForeignEnumExtensionLite));
+    Assert.assertTrue(message.hasExtension(optionalImportEnumExtensionLite ));
+
+    Assert.assertTrue(message.hasExtension(optionalStringPieceExtensionLite));
+    Assert.assertTrue(message.hasExtension(optionalCordExtensionLite));
+
+    assertEqualsExactType(101  , message.getExtension(optionalInt32ExtensionLite   ));
+    assertEqualsExactType(102L , message.getExtension(optionalInt64ExtensionLite   ));
+    assertEqualsExactType(103  , message.getExtension(optionalUint32ExtensionLite  ));
+    assertEqualsExactType(104L , message.getExtension(optionalUint64ExtensionLite  ));
+    assertEqualsExactType(105  , message.getExtension(optionalSint32ExtensionLite  ));
+    assertEqualsExactType(106L , message.getExtension(optionalSint64ExtensionLite  ));
+    assertEqualsExactType(107  , message.getExtension(optionalFixed32ExtensionLite ));
+    assertEqualsExactType(108L , message.getExtension(optionalFixed64ExtensionLite ));
+    assertEqualsExactType(109  , message.getExtension(optionalSfixed32ExtensionLite));
+    assertEqualsExactType(110L , message.getExtension(optionalSfixed64ExtensionLite));
+    assertEqualsExactType(111F , message.getExtension(optionalFloatExtensionLite   ));
+    assertEqualsExactType(112D , message.getExtension(optionalDoubleExtensionLite  ));
+    assertEqualsExactType(true , message.getExtension(optionalBoolExtensionLite    ));
+    assertEqualsExactType("115", message.getExtension(optionalStringExtensionLite  ));
+    assertEqualsExactType(toBytes("116"), message.getExtension(optionalBytesExtensionLite));
+
+    assertEqualsExactType(117, message.getExtension(optionalGroupExtensionLite         ).getA());
+    assertEqualsExactType(118, message.getExtension(optionalNestedMessageExtensionLite ).getBb());
+    assertEqualsExactType(119, message.getExtension(optionalForeignMessageExtensionLite).getC());
+    assertEqualsExactType(120, message.getExtension(optionalImportMessageExtensionLite ).getD());
+
+    assertEqualsExactType(TestAllTypesLite.NestedEnum.BAZ,
+      message.getExtension(optionalNestedEnumExtensionLite));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_BAZ,
+      message.getExtension(optionalForeignEnumExtensionLite));
+    assertEqualsExactType(ImportEnumLite.IMPORT_LITE_BAZ,
+      message.getExtension(optionalImportEnumExtensionLite));
+
+    assertEqualsExactType("124", message.getExtension(optionalStringPieceExtensionLite));
+    assertEqualsExactType("125", message.getExtension(optionalCordExtensionLite));
+
+    // -----------------------------------------------------------------
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedInt32ExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedInt64ExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedUint32ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedUint64ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSint32ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSint64ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFixed32ExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFixed64ExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSfixed32ExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSfixed64ExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFloatExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedDoubleExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedBoolExtensionLite    ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedStringExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedBytesExtensionLite   ));
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedGroupExtensionLite         ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedNestedMessageExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedForeignMessageExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedImportMessageExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedNestedEnumExtensionLite    ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedForeignEnumExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedImportEnumExtensionLite    ));
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedStringPieceExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedCordExtensionLite));
+
+    assertEqualsExactType(201  , message.getExtension(repeatedInt32ExtensionLite   , 0));
+    assertEqualsExactType(202L , message.getExtension(repeatedInt64ExtensionLite   , 0));
+    assertEqualsExactType(203  , message.getExtension(repeatedUint32ExtensionLite  , 0));
+    assertEqualsExactType(204L , message.getExtension(repeatedUint64ExtensionLite  , 0));
+    assertEqualsExactType(205  , message.getExtension(repeatedSint32ExtensionLite  , 0));
+    assertEqualsExactType(206L , message.getExtension(repeatedSint64ExtensionLite  , 0));
+    assertEqualsExactType(207  , message.getExtension(repeatedFixed32ExtensionLite , 0));
+    assertEqualsExactType(208L , message.getExtension(repeatedFixed64ExtensionLite , 0));
+    assertEqualsExactType(209  , message.getExtension(repeatedSfixed32ExtensionLite, 0));
+    assertEqualsExactType(210L , message.getExtension(repeatedSfixed64ExtensionLite, 0));
+    assertEqualsExactType(211F , message.getExtension(repeatedFloatExtensionLite   , 0));
+    assertEqualsExactType(212D , message.getExtension(repeatedDoubleExtensionLite  , 0));
+    assertEqualsExactType(true , message.getExtension(repeatedBoolExtensionLite    , 0));
+    assertEqualsExactType("215", message.getExtension(repeatedStringExtensionLite  , 0));
+    assertEqualsExactType(toBytes("216"), message.getExtension(repeatedBytesExtensionLite, 0));
+
+    assertEqualsExactType(217, message.getExtension(repeatedGroupExtensionLite         ,0).getA());
+    assertEqualsExactType(218, message.getExtension(repeatedNestedMessageExtensionLite ,0).getBb());
+    assertEqualsExactType(219, message.getExtension(repeatedForeignMessageExtensionLite,0).getC());
+    assertEqualsExactType(220, message.getExtension(repeatedImportMessageExtensionLite ,0).getD());
+
+    assertEqualsExactType(TestAllTypesLite.NestedEnum.BAR,
+      message.getExtension(repeatedNestedEnumExtensionLite, 0));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_BAR,
+      message.getExtension(repeatedForeignEnumExtensionLite, 0));
+    assertEqualsExactType(ImportEnumLite.IMPORT_LITE_BAR,
+      message.getExtension(repeatedImportEnumExtensionLite, 0));
+
+    assertEqualsExactType("224", message.getExtension(repeatedStringPieceExtensionLite, 0));
+    assertEqualsExactType("225", message.getExtension(repeatedCordExtensionLite, 0));
+
+    assertEqualsExactType(301  , message.getExtension(repeatedInt32ExtensionLite   , 1));
+    assertEqualsExactType(302L , message.getExtension(repeatedInt64ExtensionLite   , 1));
+    assertEqualsExactType(303  , message.getExtension(repeatedUint32ExtensionLite  , 1));
+    assertEqualsExactType(304L , message.getExtension(repeatedUint64ExtensionLite  , 1));
+    assertEqualsExactType(305  , message.getExtension(repeatedSint32ExtensionLite  , 1));
+    assertEqualsExactType(306L , message.getExtension(repeatedSint64ExtensionLite  , 1));
+    assertEqualsExactType(307  , message.getExtension(repeatedFixed32ExtensionLite , 1));
+    assertEqualsExactType(308L , message.getExtension(repeatedFixed64ExtensionLite , 1));
+    assertEqualsExactType(309  , message.getExtension(repeatedSfixed32ExtensionLite, 1));
+    assertEqualsExactType(310L , message.getExtension(repeatedSfixed64ExtensionLite, 1));
+    assertEqualsExactType(311F , message.getExtension(repeatedFloatExtensionLite   , 1));
+    assertEqualsExactType(312D , message.getExtension(repeatedDoubleExtensionLite  , 1));
+    assertEqualsExactType(false, message.getExtension(repeatedBoolExtensionLite    , 1));
+    assertEqualsExactType("315", message.getExtension(repeatedStringExtensionLite  , 1));
+    assertEqualsExactType(toBytes("316"), message.getExtension(repeatedBytesExtensionLite, 1));
+
+    assertEqualsExactType(317, message.getExtension(repeatedGroupExtensionLite         ,1).getA());
+    assertEqualsExactType(318, message.getExtension(repeatedNestedMessageExtensionLite ,1).getBb());
+    assertEqualsExactType(319, message.getExtension(repeatedForeignMessageExtensionLite,1).getC());
+    assertEqualsExactType(320, message.getExtension(repeatedImportMessageExtensionLite ,1).getD());
+
+    assertEqualsExactType(TestAllTypesLite.NestedEnum.BAZ,
+      message.getExtension(repeatedNestedEnumExtensionLite, 1));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_BAZ,
+      message.getExtension(repeatedForeignEnumExtensionLite, 1));
+    assertEqualsExactType(ImportEnumLite.IMPORT_LITE_BAZ,
+      message.getExtension(repeatedImportEnumExtensionLite, 1));
+
+    assertEqualsExactType("324", message.getExtension(repeatedStringPieceExtensionLite, 1));
+    assertEqualsExactType("325", message.getExtension(repeatedCordExtensionLite, 1));
+
+    // -----------------------------------------------------------------
+
+    Assert.assertTrue(message.hasExtension(defaultInt32ExtensionLite   ));
+    Assert.assertTrue(message.hasExtension(defaultInt64ExtensionLite   ));
+    Assert.assertTrue(message.hasExtension(defaultUint32ExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(defaultUint64ExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(defaultSint32ExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(defaultSint64ExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(defaultFixed32ExtensionLite ));
+    Assert.assertTrue(message.hasExtension(defaultFixed64ExtensionLite ));
+    Assert.assertTrue(message.hasExtension(defaultSfixed32ExtensionLite));
+    Assert.assertTrue(message.hasExtension(defaultSfixed64ExtensionLite));
+    Assert.assertTrue(message.hasExtension(defaultFloatExtensionLite   ));
+    Assert.assertTrue(message.hasExtension(defaultDoubleExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(defaultBoolExtensionLite    ));
+    Assert.assertTrue(message.hasExtension(defaultStringExtensionLite  ));
+    Assert.assertTrue(message.hasExtension(defaultBytesExtensionLite   ));
+
+    Assert.assertTrue(message.hasExtension(defaultNestedEnumExtensionLite ));
+    Assert.assertTrue(message.hasExtension(defaultForeignEnumExtensionLite));
+    Assert.assertTrue(message.hasExtension(defaultImportEnumExtensionLite ));
+
+    Assert.assertTrue(message.hasExtension(defaultStringPieceExtensionLite));
+    Assert.assertTrue(message.hasExtension(defaultCordExtensionLite));
+
+    assertEqualsExactType(401  , message.getExtension(defaultInt32ExtensionLite   ));
+    assertEqualsExactType(402L , message.getExtension(defaultInt64ExtensionLite   ));
+    assertEqualsExactType(403  , message.getExtension(defaultUint32ExtensionLite  ));
+    assertEqualsExactType(404L , message.getExtension(defaultUint64ExtensionLite  ));
+    assertEqualsExactType(405  , message.getExtension(defaultSint32ExtensionLite  ));
+    assertEqualsExactType(406L , message.getExtension(defaultSint64ExtensionLite  ));
+    assertEqualsExactType(407  , message.getExtension(defaultFixed32ExtensionLite ));
+    assertEqualsExactType(408L , message.getExtension(defaultFixed64ExtensionLite ));
+    assertEqualsExactType(409  , message.getExtension(defaultSfixed32ExtensionLite));
+    assertEqualsExactType(410L , message.getExtension(defaultSfixed64ExtensionLite));
+    assertEqualsExactType(411F , message.getExtension(defaultFloatExtensionLite   ));
+    assertEqualsExactType(412D , message.getExtension(defaultDoubleExtensionLite  ));
+    assertEqualsExactType(false, message.getExtension(defaultBoolExtensionLite    ));
+    assertEqualsExactType("415", message.getExtension(defaultStringExtensionLite  ));
+    assertEqualsExactType(toBytes("416"), message.getExtension(defaultBytesExtensionLite));
+
+    assertEqualsExactType(TestAllTypesLite.NestedEnum.FOO,
+      message.getExtension(defaultNestedEnumExtensionLite ));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_FOO,
+      message.getExtension(defaultForeignEnumExtensionLite));
+    assertEqualsExactType(ImportEnumLite.IMPORT_LITE_FOO,
+      message.getExtension(defaultImportEnumExtensionLite));
+
+    assertEqualsExactType("424", message.getExtension(defaultStringPieceExtensionLite));
+    assertEqualsExactType("425", message.getExtension(defaultCordExtensionLite));
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all extensions of
+   * {@code message} are cleared, and that getting the extensions returns their
+   * default values.
+   */
+  public static void assertExtensionsClear(TestAllExtensionsLite message) {
+    // hasBlah() should initially be false for all optional fields.
+    Assert.assertFalse(message.hasExtension(optionalInt32ExtensionLite   ));
+    Assert.assertFalse(message.hasExtension(optionalInt64ExtensionLite   ));
+    Assert.assertFalse(message.hasExtension(optionalUint32ExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(optionalUint64ExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(optionalSint32ExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(optionalSint64ExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(optionalFixed32ExtensionLite ));
+    Assert.assertFalse(message.hasExtension(optionalFixed64ExtensionLite ));
+    Assert.assertFalse(message.hasExtension(optionalSfixed32ExtensionLite));
+    Assert.assertFalse(message.hasExtension(optionalSfixed64ExtensionLite));
+    Assert.assertFalse(message.hasExtension(optionalFloatExtensionLite   ));
+    Assert.assertFalse(message.hasExtension(optionalDoubleExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(optionalBoolExtensionLite    ));
+    Assert.assertFalse(message.hasExtension(optionalStringExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(optionalBytesExtensionLite   ));
+
+    Assert.assertFalse(message.hasExtension(optionalGroupExtensionLite         ));
+    Assert.assertFalse(message.hasExtension(optionalNestedMessageExtensionLite ));
+    Assert.assertFalse(message.hasExtension(optionalForeignMessageExtensionLite));
+    Assert.assertFalse(message.hasExtension(optionalImportMessageExtensionLite ));
+
+    Assert.assertFalse(message.hasExtension(optionalNestedEnumExtensionLite ));
+    Assert.assertFalse(message.hasExtension(optionalForeignEnumExtensionLite));
+    Assert.assertFalse(message.hasExtension(optionalImportEnumExtensionLite ));
+
+    Assert.assertFalse(message.hasExtension(optionalStringPieceExtensionLite));
+    Assert.assertFalse(message.hasExtension(optionalCordExtensionLite));
+
+    // Optional fields without defaults are set to zero or something like it.
+    assertEqualsExactType(0    , message.getExtension(optionalInt32ExtensionLite   ));
+    assertEqualsExactType(0L   , message.getExtension(optionalInt64ExtensionLite   ));
+    assertEqualsExactType(0    , message.getExtension(optionalUint32ExtensionLite  ));
+    assertEqualsExactType(0L   , message.getExtension(optionalUint64ExtensionLite  ));
+    assertEqualsExactType(0    , message.getExtension(optionalSint32ExtensionLite  ));
+    assertEqualsExactType(0L   , message.getExtension(optionalSint64ExtensionLite  ));
+    assertEqualsExactType(0    , message.getExtension(optionalFixed32ExtensionLite ));
+    assertEqualsExactType(0L   , message.getExtension(optionalFixed64ExtensionLite ));
+    assertEqualsExactType(0    , message.getExtension(optionalSfixed32ExtensionLite));
+    assertEqualsExactType(0L   , message.getExtension(optionalSfixed64ExtensionLite));
+    assertEqualsExactType(0F   , message.getExtension(optionalFloatExtensionLite   ));
+    assertEqualsExactType(0D   , message.getExtension(optionalDoubleExtensionLite  ));
+    assertEqualsExactType(false, message.getExtension(optionalBoolExtensionLite    ));
+    assertEqualsExactType(""   , message.getExtension(optionalStringExtensionLite  ));
+    assertEqualsExactType(ByteString.EMPTY, message.getExtension(optionalBytesExtensionLite));
+
+    // Embedded messages should also be clear.
+    Assert.assertFalse(message.getExtension(optionalGroupExtensionLite         ).hasA());
+    Assert.assertFalse(message.getExtension(optionalNestedMessageExtensionLite ).hasBb());
+    Assert.assertFalse(message.getExtension(optionalForeignMessageExtensionLite).hasC());
+    Assert.assertFalse(message.getExtension(optionalImportMessageExtensionLite ).hasD());
+
+    assertEqualsExactType(0, message.getExtension(optionalGroupExtensionLite         ).getA());
+    assertEqualsExactType(0, message.getExtension(optionalNestedMessageExtensionLite ).getBb());
+    assertEqualsExactType(0, message.getExtension(optionalForeignMessageExtensionLite).getC());
+    assertEqualsExactType(0, message.getExtension(optionalImportMessageExtensionLite ).getD());
+
+    // Enums without defaults are set to the first value in the enum.
+    assertEqualsExactType(TestAllTypesLite.NestedEnum.FOO,
+      message.getExtension(optionalNestedEnumExtensionLite ));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_FOO,
+      message.getExtension(optionalForeignEnumExtensionLite));
+    assertEqualsExactType(ImportEnumLite.IMPORT_LITE_FOO,
+      message.getExtension(optionalImportEnumExtensionLite));
+
+    assertEqualsExactType("", message.getExtension(optionalStringPieceExtensionLite));
+    assertEqualsExactType("", message.getExtension(optionalCordExtensionLite));
+
+    // Repeated fields are empty.
+    Assert.assertEquals(0, message.getExtensionCount(repeatedInt32ExtensionLite   ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedInt64ExtensionLite   ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedUint32ExtensionLite  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedUint64ExtensionLite  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedSint32ExtensionLite  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedSint64ExtensionLite  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedFixed32ExtensionLite ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedFixed64ExtensionLite ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedSfixed32ExtensionLite));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedSfixed64ExtensionLite));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedFloatExtensionLite   ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedDoubleExtensionLite  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedBoolExtensionLite    ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedStringExtensionLite  ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedBytesExtensionLite   ));
+
+    Assert.assertEquals(0, message.getExtensionCount(repeatedGroupExtensionLite         ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedNestedMessageExtensionLite ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedForeignMessageExtensionLite));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedImportMessageExtensionLite ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedNestedEnumExtensionLite    ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedForeignEnumExtensionLite   ));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedImportEnumExtensionLite    ));
+
+    Assert.assertEquals(0, message.getExtensionCount(repeatedStringPieceExtensionLite));
+    Assert.assertEquals(0, message.getExtensionCount(repeatedCordExtensionLite));
+
+    // hasBlah() should also be false for all default fields.
+    Assert.assertFalse(message.hasExtension(defaultInt32ExtensionLite   ));
+    Assert.assertFalse(message.hasExtension(defaultInt64ExtensionLite   ));
+    Assert.assertFalse(message.hasExtension(defaultUint32ExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(defaultUint64ExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(defaultSint32ExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(defaultSint64ExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(defaultFixed32ExtensionLite ));
+    Assert.assertFalse(message.hasExtension(defaultFixed64ExtensionLite ));
+    Assert.assertFalse(message.hasExtension(defaultSfixed32ExtensionLite));
+    Assert.assertFalse(message.hasExtension(defaultSfixed64ExtensionLite));
+    Assert.assertFalse(message.hasExtension(defaultFloatExtensionLite   ));
+    Assert.assertFalse(message.hasExtension(defaultDoubleExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(defaultBoolExtensionLite    ));
+    Assert.assertFalse(message.hasExtension(defaultStringExtensionLite  ));
+    Assert.assertFalse(message.hasExtension(defaultBytesExtensionLite   ));
+
+    Assert.assertFalse(message.hasExtension(defaultNestedEnumExtensionLite ));
+    Assert.assertFalse(message.hasExtension(defaultForeignEnumExtensionLite));
+    Assert.assertFalse(message.hasExtension(defaultImportEnumExtensionLite ));
+
+    Assert.assertFalse(message.hasExtension(defaultStringPieceExtensionLite));
+    Assert.assertFalse(message.hasExtension(defaultCordExtensionLite));
+
+    // Fields with defaults have their default values (duh).
+    assertEqualsExactType( 41    , message.getExtension(defaultInt32ExtensionLite   ));
+    assertEqualsExactType( 42L   , message.getExtension(defaultInt64ExtensionLite   ));
+    assertEqualsExactType( 43    , message.getExtension(defaultUint32ExtensionLite  ));
+    assertEqualsExactType( 44L   , message.getExtension(defaultUint64ExtensionLite  ));
+    assertEqualsExactType(-45    , message.getExtension(defaultSint32ExtensionLite  ));
+    assertEqualsExactType( 46L   , message.getExtension(defaultSint64ExtensionLite  ));
+    assertEqualsExactType( 47    , message.getExtension(defaultFixed32ExtensionLite ));
+    assertEqualsExactType( 48L   , message.getExtension(defaultFixed64ExtensionLite ));
+    assertEqualsExactType( 49    , message.getExtension(defaultSfixed32ExtensionLite));
+    assertEqualsExactType(-50L   , message.getExtension(defaultSfixed64ExtensionLite));
+    assertEqualsExactType( 51.5F , message.getExtension(defaultFloatExtensionLite   ));
+    assertEqualsExactType( 52e3D , message.getExtension(defaultDoubleExtensionLite  ));
+    assertEqualsExactType(true   , message.getExtension(defaultBoolExtensionLite    ));
+    assertEqualsExactType("hello", message.getExtension(defaultStringExtensionLite  ));
+    assertEqualsExactType(toBytes("world"), message.getExtension(defaultBytesExtensionLite));
+
+    assertEqualsExactType(TestAllTypesLite.NestedEnum.BAR,
+      message.getExtension(defaultNestedEnumExtensionLite ));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_BAR,
+      message.getExtension(defaultForeignEnumExtensionLite));
+    assertEqualsExactType(ImportEnumLite.IMPORT_LITE_BAR,
+      message.getExtension(defaultImportEnumExtensionLite));
+
+    assertEqualsExactType("abc", message.getExtension(defaultStringPieceExtensionLite));
+    assertEqualsExactType("123", message.getExtension(defaultCordExtensionLite));
+  }
+
+  // -------------------------------------------------------------------
+
+  /**
+   * Assert (using {@code junit.framework.Assert}} that all extensions of
+   * {@code message} are set to the values assigned by {@code setAllExtensions}
+   * followed by {@code modifyRepeatedExtensions}.
+   */
+  public static void assertRepeatedExtensionsModified(
+      TestAllExtensionsLite message) {
+    // ModifyRepeatedFields only sets the second repeated element of each
+    // field.  In addition to verifying this, we also verify that the first
+    // element and size were *not* modified.
+    Assert.assertEquals(2, message.getExtensionCount(repeatedInt32ExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedInt64ExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedUint32ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedUint64ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSint32ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSint64ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFixed32ExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFixed64ExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSfixed32ExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedSfixed64ExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedFloatExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedDoubleExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedBoolExtensionLite    ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedStringExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedBytesExtensionLite   ));
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedGroupExtensionLite         ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedNestedMessageExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedForeignMessageExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedImportMessageExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedNestedEnumExtensionLite    ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedForeignEnumExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedImportEnumExtensionLite    ));
+
+    Assert.assertEquals(2, message.getExtensionCount(repeatedStringPieceExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(repeatedCordExtensionLite));
+
+    assertEqualsExactType(201  , message.getExtension(repeatedInt32ExtensionLite   , 0));
+    assertEqualsExactType(202L , message.getExtension(repeatedInt64ExtensionLite   , 0));
+    assertEqualsExactType(203  , message.getExtension(repeatedUint32ExtensionLite  , 0));
+    assertEqualsExactType(204L , message.getExtension(repeatedUint64ExtensionLite  , 0));
+    assertEqualsExactType(205  , message.getExtension(repeatedSint32ExtensionLite  , 0));
+    assertEqualsExactType(206L , message.getExtension(repeatedSint64ExtensionLite  , 0));
+    assertEqualsExactType(207  , message.getExtension(repeatedFixed32ExtensionLite , 0));
+    assertEqualsExactType(208L , message.getExtension(repeatedFixed64ExtensionLite , 0));
+    assertEqualsExactType(209  , message.getExtension(repeatedSfixed32ExtensionLite, 0));
+    assertEqualsExactType(210L , message.getExtension(repeatedSfixed64ExtensionLite, 0));
+    assertEqualsExactType(211F , message.getExtension(repeatedFloatExtensionLite   , 0));
+    assertEqualsExactType(212D , message.getExtension(repeatedDoubleExtensionLite  , 0));
+    assertEqualsExactType(true , message.getExtension(repeatedBoolExtensionLite    , 0));
+    assertEqualsExactType("215", message.getExtension(repeatedStringExtensionLite  , 0));
+    assertEqualsExactType(toBytes("216"), message.getExtension(repeatedBytesExtensionLite, 0));
+
+    assertEqualsExactType(217, message.getExtension(repeatedGroupExtensionLite         ,0).getA());
+    assertEqualsExactType(218, message.getExtension(repeatedNestedMessageExtensionLite ,0).getBb());
+    assertEqualsExactType(219, message.getExtension(repeatedForeignMessageExtensionLite,0).getC());
+    assertEqualsExactType(220, message.getExtension(repeatedImportMessageExtensionLite ,0).getD());
+
+    assertEqualsExactType(TestAllTypesLite.NestedEnum.BAR,
+      message.getExtension(repeatedNestedEnumExtensionLite, 0));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_BAR,
+      message.getExtension(repeatedForeignEnumExtensionLite, 0));
+    assertEqualsExactType(ImportEnumLite.IMPORT_LITE_BAR,
+      message.getExtension(repeatedImportEnumExtensionLite, 0));
+
+    assertEqualsExactType("224", message.getExtension(repeatedStringPieceExtensionLite, 0));
+    assertEqualsExactType("225", message.getExtension(repeatedCordExtensionLite, 0));
+
+    // Actually verify the second (modified) elements now.
+    assertEqualsExactType(501  , message.getExtension(repeatedInt32ExtensionLite   , 1));
+    assertEqualsExactType(502L , message.getExtension(repeatedInt64ExtensionLite   , 1));
+    assertEqualsExactType(503  , message.getExtension(repeatedUint32ExtensionLite  , 1));
+    assertEqualsExactType(504L , message.getExtension(repeatedUint64ExtensionLite  , 1));
+    assertEqualsExactType(505  , message.getExtension(repeatedSint32ExtensionLite  , 1));
+    assertEqualsExactType(506L , message.getExtension(repeatedSint64ExtensionLite  , 1));
+    assertEqualsExactType(507  , message.getExtension(repeatedFixed32ExtensionLite , 1));
+    assertEqualsExactType(508L , message.getExtension(repeatedFixed64ExtensionLite , 1));
+    assertEqualsExactType(509  , message.getExtension(repeatedSfixed32ExtensionLite, 1));
+    assertEqualsExactType(510L , message.getExtension(repeatedSfixed64ExtensionLite, 1));
+    assertEqualsExactType(511F , message.getExtension(repeatedFloatExtensionLite   , 1));
+    assertEqualsExactType(512D , message.getExtension(repeatedDoubleExtensionLite  , 1));
+    assertEqualsExactType(true , message.getExtension(repeatedBoolExtensionLite    , 1));
+    assertEqualsExactType("515", message.getExtension(repeatedStringExtensionLite  , 1));
+    assertEqualsExactType(toBytes("516"), message.getExtension(repeatedBytesExtensionLite, 1));
+
+    assertEqualsExactType(517, message.getExtension(repeatedGroupExtensionLite         ,1).getA());
+    assertEqualsExactType(518, message.getExtension(repeatedNestedMessageExtensionLite ,1).getBb());
+    assertEqualsExactType(519, message.getExtension(repeatedForeignMessageExtensionLite,1).getC());
+    assertEqualsExactType(520, message.getExtension(repeatedImportMessageExtensionLite ,1).getD());
+
+    assertEqualsExactType(TestAllTypesLite.NestedEnum.FOO,
+      message.getExtension(repeatedNestedEnumExtensionLite, 1));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_FOO,
+      message.getExtension(repeatedForeignEnumExtensionLite, 1));
+    assertEqualsExactType(ImportEnumLite.IMPORT_LITE_FOO,
+      message.getExtension(repeatedImportEnumExtensionLite, 1));
+
+    assertEqualsExactType("524", message.getExtension(repeatedStringPieceExtensionLite, 1));
+    assertEqualsExactType("525", message.getExtension(repeatedCordExtensionLite, 1));
+  }
+
+  public static void setPackedExtensions(TestPackedExtensionsLite.Builder message) {
+    message.addExtension(packedInt32ExtensionLite   , 601);
+    message.addExtension(packedInt64ExtensionLite   , 602L);
+    message.addExtension(packedUint32ExtensionLite  , 603);
+    message.addExtension(packedUint64ExtensionLite  , 604L);
+    message.addExtension(packedSint32ExtensionLite  , 605);
+    message.addExtension(packedSint64ExtensionLite  , 606L);
+    message.addExtension(packedFixed32ExtensionLite , 607);
+    message.addExtension(packedFixed64ExtensionLite , 608L);
+    message.addExtension(packedSfixed32ExtensionLite, 609);
+    message.addExtension(packedSfixed64ExtensionLite, 610L);
+    message.addExtension(packedFloatExtensionLite   , 611F);
+    message.addExtension(packedDoubleExtensionLite  , 612D);
+    message.addExtension(packedBoolExtensionLite    , true);
+    message.addExtension(packedEnumExtensionLite, ForeignEnumLite.FOREIGN_LITE_BAR);
+    // Add a second one of each field.
+    message.addExtension(packedInt32ExtensionLite   , 701);
+    message.addExtension(packedInt64ExtensionLite   , 702L);
+    message.addExtension(packedUint32ExtensionLite  , 703);
+    message.addExtension(packedUint64ExtensionLite  , 704L);
+    message.addExtension(packedSint32ExtensionLite  , 705);
+    message.addExtension(packedSint64ExtensionLite  , 706L);
+    message.addExtension(packedFixed32ExtensionLite , 707);
+    message.addExtension(packedFixed64ExtensionLite , 708L);
+    message.addExtension(packedSfixed32ExtensionLite, 709);
+    message.addExtension(packedSfixed64ExtensionLite, 710L);
+    message.addExtension(packedFloatExtensionLite   , 711F);
+    message.addExtension(packedDoubleExtensionLite  , 712D);
+    message.addExtension(packedBoolExtensionLite    , false);
+    message.addExtension(packedEnumExtensionLite, ForeignEnumLite.FOREIGN_LITE_BAZ);
+  }
+
+  public static void assertPackedExtensionsSet(TestPackedExtensionsLite message) {
+    Assert.assertEquals(2, message.getExtensionCount(packedInt32ExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(packedInt64ExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(packedUint32ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedUint64ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedSint32ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedSint64ExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedFixed32ExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(packedFixed64ExtensionLite ));
+    Assert.assertEquals(2, message.getExtensionCount(packedSfixed32ExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(packedSfixed64ExtensionLite));
+    Assert.assertEquals(2, message.getExtensionCount(packedFloatExtensionLite   ));
+    Assert.assertEquals(2, message.getExtensionCount(packedDoubleExtensionLite  ));
+    Assert.assertEquals(2, message.getExtensionCount(packedBoolExtensionLite    ));
+    Assert.assertEquals(2, message.getExtensionCount(packedEnumExtensionLite));
+    assertEqualsExactType(601  , message.getExtension(packedInt32ExtensionLite   , 0));
+    assertEqualsExactType(602L , message.getExtension(packedInt64ExtensionLite   , 0));
+    assertEqualsExactType(603  , message.getExtension(packedUint32ExtensionLite  , 0));
+    assertEqualsExactType(604L , message.getExtension(packedUint64ExtensionLite  , 0));
+    assertEqualsExactType(605  , message.getExtension(packedSint32ExtensionLite  , 0));
+    assertEqualsExactType(606L , message.getExtension(packedSint64ExtensionLite  , 0));
+    assertEqualsExactType(607  , message.getExtension(packedFixed32ExtensionLite , 0));
+    assertEqualsExactType(608L , message.getExtension(packedFixed64ExtensionLite , 0));
+    assertEqualsExactType(609  , message.getExtension(packedSfixed32ExtensionLite, 0));
+    assertEqualsExactType(610L , message.getExtension(packedSfixed64ExtensionLite, 0));
+    assertEqualsExactType(611F , message.getExtension(packedFloatExtensionLite   , 0));
+    assertEqualsExactType(612D , message.getExtension(packedDoubleExtensionLite  , 0));
+    assertEqualsExactType(true , message.getExtension(packedBoolExtensionLite    , 0));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_BAR,
+                          message.getExtension(packedEnumExtensionLite, 0));
+    assertEqualsExactType(701  , message.getExtension(packedInt32ExtensionLite   , 1));
+    assertEqualsExactType(702L , message.getExtension(packedInt64ExtensionLite   , 1));
+    assertEqualsExactType(703  , message.getExtension(packedUint32ExtensionLite  , 1));
+    assertEqualsExactType(704L , message.getExtension(packedUint64ExtensionLite  , 1));
+    assertEqualsExactType(705  , message.getExtension(packedSint32ExtensionLite  , 1));
+    assertEqualsExactType(706L , message.getExtension(packedSint64ExtensionLite  , 1));
+    assertEqualsExactType(707  , message.getExtension(packedFixed32ExtensionLite , 1));
+    assertEqualsExactType(708L , message.getExtension(packedFixed64ExtensionLite , 1));
+    assertEqualsExactType(709  , message.getExtension(packedSfixed32ExtensionLite, 1));
+    assertEqualsExactType(710L , message.getExtension(packedSfixed64ExtensionLite, 1));
+    assertEqualsExactType(711F , message.getExtension(packedFloatExtensionLite   , 1));
+    assertEqualsExactType(712D , message.getExtension(packedDoubleExtensionLite  , 1));
+    assertEqualsExactType(false, message.getExtension(packedBoolExtensionLite    , 1));
+    assertEqualsExactType(ForeignEnumLite.FOREIGN_LITE_BAZ,
+                          message.getExtension(packedEnumExtensionLite, 1));
+  }
+
+  // =================================================================
+
+  /**
+   * Performs the same things that the methods of {@code TestUtil} do, but
+   * via the reflection interface.  This is its own class because it needs
+   * to know what descriptor to use.
+   */
+  public static class ReflectionTester {
+    private final Descriptors.Descriptor baseDescriptor;
+    private final ExtensionRegistry extensionRegistry;
+
+    private final Descriptors.FileDescriptor file;
+    private final Descriptors.FileDescriptor importFile;
+
+    private final Descriptors.Descriptor optionalGroup;
+    private final Descriptors.Descriptor repeatedGroup;
+    private final Descriptors.Descriptor nestedMessage;
+    private final Descriptors.Descriptor foreignMessage;
+    private final Descriptors.Descriptor importMessage;
+
+    private final Descriptors.FieldDescriptor groupA;
+    private final Descriptors.FieldDescriptor repeatedGroupA;
+    private final Descriptors.FieldDescriptor nestedB;
+    private final Descriptors.FieldDescriptor foreignC;
+    private final Descriptors.FieldDescriptor importD;
+
+    private final Descriptors.EnumDescriptor nestedEnum;
+    private final Descriptors.EnumDescriptor foreignEnum;
+    private final Descriptors.EnumDescriptor importEnum;
+
+    private final Descriptors.EnumValueDescriptor nestedFoo;
+    private final Descriptors.EnumValueDescriptor nestedBar;
+    private final Descriptors.EnumValueDescriptor nestedBaz;
+    private final Descriptors.EnumValueDescriptor foreignFoo;
+    private final Descriptors.EnumValueDescriptor foreignBar;
+    private final Descriptors.EnumValueDescriptor foreignBaz;
+    private final Descriptors.EnumValueDescriptor importFoo;
+    private final Descriptors.EnumValueDescriptor importBar;
+    private final Descriptors.EnumValueDescriptor importBaz;
+
+    /**
+     * Construct a {@code ReflectionTester} that will expect messages using
+     * the given descriptor.
+     *
+     * Normally {@code baseDescriptor} should be a descriptor for the type
+     * {@code TestAllTypes}, defined in
+     * {@code google/protobuf/unittest.proto}.  However, if
+     * {@code extensionRegistry} is non-null, then {@code baseDescriptor} should
+     * be for {@code TestAllExtensions} instead, and instead of reading and
+     * writing normal fields, the tester will read and write extensions.
+     * All of {@code TestAllExtensions}' extensions must be registered in the
+     * registry.
+     */
+    public ReflectionTester(Descriptors.Descriptor baseDescriptor,
+                            ExtensionRegistry extensionRegistry) {
+      this.baseDescriptor = baseDescriptor;
+      this.extensionRegistry = extensionRegistry;
+
+      this.file = baseDescriptor.getFile();
+      Assert.assertEquals(1, file.getDependencies().size());
+      this.importFile = file.getDependencies().get(0);
+
+      Descriptors.Descriptor testAllTypes;
+      if (baseDescriptor.getName() == "TestAllTypes") {
+        testAllTypes = baseDescriptor;
+      } else {
+        testAllTypes = file.findMessageTypeByName("TestAllTypes");
+        Assert.assertNotNull(testAllTypes);
+      }
+
+      if (extensionRegistry == null) {
+        // Use testAllTypes, rather than baseDescriptor, to allow
+        // initialization using TestPackedTypes descriptors. These objects
+        // won't be used by the methods for packed fields.
+        this.optionalGroup =
+          testAllTypes.findNestedTypeByName("OptionalGroup");
+        this.repeatedGroup =
+          testAllTypes.findNestedTypeByName("RepeatedGroup");
+      } else {
+        this.optionalGroup =
+          file.findMessageTypeByName("OptionalGroup_extension");
+        this.repeatedGroup =
+          file.findMessageTypeByName("RepeatedGroup_extension");
+      }
+      this.nestedMessage = testAllTypes.findNestedTypeByName("NestedMessage");
+      this.foreignMessage = file.findMessageTypeByName("ForeignMessage");
+      this.importMessage = importFile.findMessageTypeByName("ImportMessage");
+
+      this.nestedEnum = testAllTypes.findEnumTypeByName("NestedEnum");
+      this.foreignEnum = file.findEnumTypeByName("ForeignEnum");
+      this.importEnum = importFile.findEnumTypeByName("ImportEnum");
+
+      Assert.assertNotNull(optionalGroup );
+      Assert.assertNotNull(repeatedGroup );
+      Assert.assertNotNull(nestedMessage );
+      Assert.assertNotNull(foreignMessage);
+      Assert.assertNotNull(importMessage );
+      Assert.assertNotNull(nestedEnum    );
+      Assert.assertNotNull(foreignEnum   );
+      Assert.assertNotNull(importEnum    );
+
+      this.nestedB  = nestedMessage .findFieldByName("bb");
+      this.foreignC = foreignMessage.findFieldByName("c");
+      this.importD  = importMessage .findFieldByName("d");
+      this.nestedFoo = nestedEnum.findValueByName("FOO");
+      this.nestedBar = nestedEnum.findValueByName("BAR");
+      this.nestedBaz = nestedEnum.findValueByName("BAZ");
+      this.foreignFoo = foreignEnum.findValueByName("FOREIGN_FOO");
+      this.foreignBar = foreignEnum.findValueByName("FOREIGN_BAR");
+      this.foreignBaz = foreignEnum.findValueByName("FOREIGN_BAZ");
+      this.importFoo = importEnum.findValueByName("IMPORT_FOO");
+      this.importBar = importEnum.findValueByName("IMPORT_BAR");
+      this.importBaz = importEnum.findValueByName("IMPORT_BAZ");
+
+      this.groupA = optionalGroup.findFieldByName("a");
+      this.repeatedGroupA = repeatedGroup.findFieldByName("a");
+
+      Assert.assertNotNull(groupA        );
+      Assert.assertNotNull(repeatedGroupA);
+      Assert.assertNotNull(nestedB       );
+      Assert.assertNotNull(foreignC      );
+      Assert.assertNotNull(importD       );
+      Assert.assertNotNull(nestedFoo     );
+      Assert.assertNotNull(nestedBar     );
+      Assert.assertNotNull(nestedBaz     );
+      Assert.assertNotNull(foreignFoo    );
+      Assert.assertNotNull(foreignBar    );
+      Assert.assertNotNull(foreignBaz    );
+      Assert.assertNotNull(importFoo     );
+      Assert.assertNotNull(importBar     );
+      Assert.assertNotNull(importBaz     );
+    }
+
+    /**
+     * Shorthand to get a FieldDescriptor for a field of unittest::TestAllTypes.
+     */
+    private Descriptors.FieldDescriptor f(String name) {
+      Descriptors.FieldDescriptor result;
+      if (extensionRegistry == null) {
+        result = baseDescriptor.findFieldByName(name);
+      } else {
+        result = file.findExtensionByName(name + "_extension");
+      }
+      Assert.assertNotNull(result);
+      return result;
+    }
+
+    /**
+     * Calls {@code parent.newBuilderForField()} or uses the
+     * {@code ExtensionRegistry} to find an appropriate builder, depending
+     * on what type is being tested.
+     */
+    private Message.Builder newBuilderForField(
+        Message.Builder parent, Descriptors.FieldDescriptor field) {
+      if (extensionRegistry == null) {
+        return parent.newBuilderForField(field);
+      } else {
+        ExtensionRegistry.ExtensionInfo extension =
+          extensionRegistry.findExtensionByNumber(field.getContainingType(),
+                                                  field.getNumber());
+        Assert.assertNotNull(extension);
+        Assert.assertNotNull(extension.defaultInstance);
+        return extension.defaultInstance.newBuilderForType();
+      }
+    }
+
+    // -------------------------------------------------------------------
+
+    /**
+     * Set every field of {@code message} to the values expected by
+     * {@code assertAllFieldsSet()}, using the {@link Message.Builder}
+     * reflection interface.
+     */
+    void setAllFieldsViaReflection(Message.Builder message) {
+      message.setField(f("optional_int32"   ), 101 );
+      message.setField(f("optional_int64"   ), 102L);
+      message.setField(f("optional_uint32"  ), 103 );
+      message.setField(f("optional_uint64"  ), 104L);
+      message.setField(f("optional_sint32"  ), 105 );
+      message.setField(f("optional_sint64"  ), 106L);
+      message.setField(f("optional_fixed32" ), 107 );
+      message.setField(f("optional_fixed64" ), 108L);
+      message.setField(f("optional_sfixed32"), 109 );
+      message.setField(f("optional_sfixed64"), 110L);
+      message.setField(f("optional_float"   ), 111F);
+      message.setField(f("optional_double"  ), 112D);
+      message.setField(f("optional_bool"    ), true);
+      message.setField(f("optional_string"  ), "115");
+      message.setField(f("optional_bytes"   ), toBytes("116"));
+
+      message.setField(f("optionalgroup"),
+        newBuilderForField(message, f("optionalgroup"))
+               .setField(groupA, 117).build());
+      message.setField(f("optional_nested_message"),
+        newBuilderForField(message, f("optional_nested_message"))
+               .setField(nestedB, 118).build());
+      message.setField(f("optional_foreign_message"),
+        newBuilderForField(message, f("optional_foreign_message"))
+               .setField(foreignC, 119).build());
+      message.setField(f("optional_import_message"),
+        newBuilderForField(message, f("optional_import_message"))
+               .setField(importD, 120).build());
+
+      message.setField(f("optional_nested_enum" ),  nestedBaz);
+      message.setField(f("optional_foreign_enum"), foreignBaz);
+      message.setField(f("optional_import_enum" ),  importBaz);
+
+      message.setField(f("optional_string_piece" ), "124");
+      message.setField(f("optional_cord" ), "125");
+
+      // -----------------------------------------------------------------
+
+      message.addRepeatedField(f("repeated_int32"   ), 201 );
+      message.addRepeatedField(f("repeated_int64"   ), 202L);
+      message.addRepeatedField(f("repeated_uint32"  ), 203 );
+      message.addRepeatedField(f("repeated_uint64"  ), 204L);
+      message.addRepeatedField(f("repeated_sint32"  ), 205 );
+      message.addRepeatedField(f("repeated_sint64"  ), 206L);
+      message.addRepeatedField(f("repeated_fixed32" ), 207 );
+      message.addRepeatedField(f("repeated_fixed64" ), 208L);
+      message.addRepeatedField(f("repeated_sfixed32"), 209 );
+      message.addRepeatedField(f("repeated_sfixed64"), 210L);
+      message.addRepeatedField(f("repeated_float"   ), 211F);
+      message.addRepeatedField(f("repeated_double"  ), 212D);
+      message.addRepeatedField(f("repeated_bool"    ), true);
+      message.addRepeatedField(f("repeated_string"  ), "215");
+      message.addRepeatedField(f("repeated_bytes"   ), toBytes("216"));
+
+      message.addRepeatedField(f("repeatedgroup"),
+        newBuilderForField(message, f("repeatedgroup"))
+               .setField(repeatedGroupA, 217).build());
+      message.addRepeatedField(f("repeated_nested_message"),
+        newBuilderForField(message, f("repeated_nested_message"))
+               .setField(nestedB, 218).build());
+      message.addRepeatedField(f("repeated_foreign_message"),
+        newBuilderForField(message, f("repeated_foreign_message"))
+               .setField(foreignC, 219).build());
+      message.addRepeatedField(f("repeated_import_message"),
+        newBuilderForField(message, f("repeated_import_message"))
+               .setField(importD, 220).build());
+
+      message.addRepeatedField(f("repeated_nested_enum" ),  nestedBar);
+      message.addRepeatedField(f("repeated_foreign_enum"), foreignBar);
+      message.addRepeatedField(f("repeated_import_enum" ),  importBar);
+
+      message.addRepeatedField(f("repeated_string_piece" ), "224");
+      message.addRepeatedField(f("repeated_cord" ), "225");
+
+      // Add a second one of each field.
+      message.addRepeatedField(f("repeated_int32"   ), 301 );
+      message.addRepeatedField(f("repeated_int64"   ), 302L);
+      message.addRepeatedField(f("repeated_uint32"  ), 303 );
+      message.addRepeatedField(f("repeated_uint64"  ), 304L);
+      message.addRepeatedField(f("repeated_sint32"  ), 305 );
+      message.addRepeatedField(f("repeated_sint64"  ), 306L);
+      message.addRepeatedField(f("repeated_fixed32" ), 307 );
+      message.addRepeatedField(f("repeated_fixed64" ), 308L);
+      message.addRepeatedField(f("repeated_sfixed32"), 309 );
+      message.addRepeatedField(f("repeated_sfixed64"), 310L);
+      message.addRepeatedField(f("repeated_float"   ), 311F);
+      message.addRepeatedField(f("repeated_double"  ), 312D);
+      message.addRepeatedField(f("repeated_bool"    ), false);
+      message.addRepeatedField(f("repeated_string"  ), "315");
+      message.addRepeatedField(f("repeated_bytes"   ), toBytes("316"));
+
+      message.addRepeatedField(f("repeatedgroup"),
+        newBuilderForField(message, f("repeatedgroup"))
+               .setField(repeatedGroupA, 317).build());
+      message.addRepeatedField(f("repeated_nested_message"),
+        newBuilderForField(message, f("repeated_nested_message"))
+               .setField(nestedB, 318).build());
+      message.addRepeatedField(f("repeated_foreign_message"),
+        newBuilderForField(message, f("repeated_foreign_message"))
+               .setField(foreignC, 319).build());
+      message.addRepeatedField(f("repeated_import_message"),
+        newBuilderForField(message, f("repeated_import_message"))
+               .setField(importD, 320).build());
+
+      message.addRepeatedField(f("repeated_nested_enum" ),  nestedBaz);
+      message.addRepeatedField(f("repeated_foreign_enum"), foreignBaz);
+      message.addRepeatedField(f("repeated_import_enum" ),  importBaz);
+
+      message.addRepeatedField(f("repeated_string_piece" ), "324");
+      message.addRepeatedField(f("repeated_cord" ), "325");
+
+      // -----------------------------------------------------------------
+
+      message.setField(f("default_int32"   ), 401 );
+      message.setField(f("default_int64"   ), 402L);
+      message.setField(f("default_uint32"  ), 403 );
+      message.setField(f("default_uint64"  ), 404L);
+      message.setField(f("default_sint32"  ), 405 );
+      message.setField(f("default_sint64"  ), 406L);
+      message.setField(f("default_fixed32" ), 407 );
+      message.setField(f("default_fixed64" ), 408L);
+      message.setField(f("default_sfixed32"), 409 );
+      message.setField(f("default_sfixed64"), 410L);
+      message.setField(f("default_float"   ), 411F);
+      message.setField(f("default_double"  ), 412D);
+      message.setField(f("default_bool"    ), false);
+      message.setField(f("default_string"  ), "415");
+      message.setField(f("default_bytes"   ), toBytes("416"));
+
+      message.setField(f("default_nested_enum" ),  nestedFoo);
+      message.setField(f("default_foreign_enum"), foreignFoo);
+      message.setField(f("default_import_enum" ),  importFoo);
+
+      message.setField(f("default_string_piece" ), "424");
+      message.setField(f("default_cord" ), "425");
+    }
+
+    // -------------------------------------------------------------------
+
+    /**
+     * Modify the repeated fields of {@code message} to contain the values
+     * expected by {@code assertRepeatedFieldsModified()}, using the
+     * {@link Message.Builder} reflection interface.
+     */
+    void modifyRepeatedFieldsViaReflection(Message.Builder message) {
+      message.setRepeatedField(f("repeated_int32"   ), 1, 501 );
+      message.setRepeatedField(f("repeated_int64"   ), 1, 502L);
+      message.setRepeatedField(f("repeated_uint32"  ), 1, 503 );
+      message.setRepeatedField(f("repeated_uint64"  ), 1, 504L);
+      message.setRepeatedField(f("repeated_sint32"  ), 1, 505 );
+      message.setRepeatedField(f("repeated_sint64"  ), 1, 506L);
+      message.setRepeatedField(f("repeated_fixed32" ), 1, 507 );
+      message.setRepeatedField(f("repeated_fixed64" ), 1, 508L);
+      message.setRepeatedField(f("repeated_sfixed32"), 1, 509 );
+      message.setRepeatedField(f("repeated_sfixed64"), 1, 510L);
+      message.setRepeatedField(f("repeated_float"   ), 1, 511F);
+      message.setRepeatedField(f("repeated_double"  ), 1, 512D);
+      message.setRepeatedField(f("repeated_bool"    ), 1, true);
+      message.setRepeatedField(f("repeated_string"  ), 1, "515");
+      message.setRepeatedField(f("repeated_bytes"   ), 1, toBytes("516"));
+
+      message.setRepeatedField(f("repeatedgroup"), 1,
+        newBuilderForField(message, f("repeatedgroup"))
+               .setField(repeatedGroupA, 517).build());
+      message.setRepeatedField(f("repeated_nested_message"), 1,
+        newBuilderForField(message, f("repeated_nested_message"))
+               .setField(nestedB, 518).build());
+      message.setRepeatedField(f("repeated_foreign_message"), 1,
+        newBuilderForField(message, f("repeated_foreign_message"))
+               .setField(foreignC, 519).build());
+      message.setRepeatedField(f("repeated_import_message"), 1,
+        newBuilderForField(message, f("repeated_import_message"))
+               .setField(importD, 520).build());
+
+      message.setRepeatedField(f("repeated_nested_enum" ), 1,  nestedFoo);
+      message.setRepeatedField(f("repeated_foreign_enum"), 1, foreignFoo);
+      message.setRepeatedField(f("repeated_import_enum" ), 1,  importFoo);
+
+      message.setRepeatedField(f("repeated_string_piece"), 1, "524");
+      message.setRepeatedField(f("repeated_cord"), 1, "525");
+    }
+
+    // -------------------------------------------------------------------
+
+    /**
+     * Assert (using {@code junit.framework.Assert}} that all fields of
+     * {@code message} are set to the values assigned by {@code setAllFields},
+     * using the {@link Message} reflection interface.
+     */
+    public void assertAllFieldsSetViaReflection(Message message) {
+      Assert.assertTrue(message.hasField(f("optional_int32"   )));
+      Assert.assertTrue(message.hasField(f("optional_int64"   )));
+      Assert.assertTrue(message.hasField(f("optional_uint32"  )));
+      Assert.assertTrue(message.hasField(f("optional_uint64"  )));
+      Assert.assertTrue(message.hasField(f("optional_sint32"  )));
+      Assert.assertTrue(message.hasField(f("optional_sint64"  )));
+      Assert.assertTrue(message.hasField(f("optional_fixed32" )));
+      Assert.assertTrue(message.hasField(f("optional_fixed64" )));
+      Assert.assertTrue(message.hasField(f("optional_sfixed32")));
+      Assert.assertTrue(message.hasField(f("optional_sfixed64")));
+      Assert.assertTrue(message.hasField(f("optional_float"   )));
+      Assert.assertTrue(message.hasField(f("optional_double"  )));
+      Assert.assertTrue(message.hasField(f("optional_bool"    )));
+      Assert.assertTrue(message.hasField(f("optional_string"  )));
+      Assert.assertTrue(message.hasField(f("optional_bytes"   )));
+
+      Assert.assertTrue(message.hasField(f("optionalgroup"           )));
+      Assert.assertTrue(message.hasField(f("optional_nested_message" )));
+      Assert.assertTrue(message.hasField(f("optional_foreign_message")));
+      Assert.assertTrue(message.hasField(f("optional_import_message" )));
+
+      Assert.assertTrue(
+        ((Message)message.getField(f("optionalgroup"))).hasField(groupA));
+      Assert.assertTrue(
+        ((Message)message.getField(f("optional_nested_message")))
+                         .hasField(nestedB));
+      Assert.assertTrue(
+        ((Message)message.getField(f("optional_foreign_message")))
+                         .hasField(foreignC));
+      Assert.assertTrue(
+        ((Message)message.getField(f("optional_import_message")))
+                         .hasField(importD));
+
+      Assert.assertTrue(message.hasField(f("optional_nested_enum" )));
+      Assert.assertTrue(message.hasField(f("optional_foreign_enum")));
+      Assert.assertTrue(message.hasField(f("optional_import_enum" )));
+
+      Assert.assertTrue(message.hasField(f("optional_string_piece")));
+      Assert.assertTrue(message.hasField(f("optional_cord")));
+
+      Assert.assertEquals(101  , message.getField(f("optional_int32"   )));
+      Assert.assertEquals(102L , message.getField(f("optional_int64"   )));
+      Assert.assertEquals(103  , message.getField(f("optional_uint32"  )));
+      Assert.assertEquals(104L , message.getField(f("optional_uint64"  )));
+      Assert.assertEquals(105  , message.getField(f("optional_sint32"  )));
+      Assert.assertEquals(106L , message.getField(f("optional_sint64"  )));
+      Assert.assertEquals(107  , message.getField(f("optional_fixed32" )));
+      Assert.assertEquals(108L , message.getField(f("optional_fixed64" )));
+      Assert.assertEquals(109  , message.getField(f("optional_sfixed32")));
+      Assert.assertEquals(110L , message.getField(f("optional_sfixed64")));
+      Assert.assertEquals(111F , message.getField(f("optional_float"   )));
+      Assert.assertEquals(112D , message.getField(f("optional_double"  )));
+      Assert.assertEquals(true , message.getField(f("optional_bool"    )));
+      Assert.assertEquals("115", message.getField(f("optional_string"  )));
+      Assert.assertEquals(toBytes("116"), message.getField(f("optional_bytes")));
+
+      Assert.assertEquals(117,
+        ((Message)message.getField(f("optionalgroup"))).getField(groupA));
+      Assert.assertEquals(118,
+        ((Message)message.getField(f("optional_nested_message")))
+                         .getField(nestedB));
+      Assert.assertEquals(119,
+        ((Message)message.getField(f("optional_foreign_message")))
+                         .getField(foreignC));
+      Assert.assertEquals(120,
+        ((Message)message.getField(f("optional_import_message")))
+                         .getField(importD));
+
+      Assert.assertEquals( nestedBaz, message.getField(f("optional_nested_enum" )));
+      Assert.assertEquals(foreignBaz, message.getField(f("optional_foreign_enum")));
+      Assert.assertEquals( importBaz, message.getField(f("optional_import_enum" )));
+
+      Assert.assertEquals("124", message.getField(f("optional_string_piece")));
+      Assert.assertEquals("125", message.getField(f("optional_cord")));
+
+      // -----------------------------------------------------------------
+
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_int32"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_int64"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_uint32"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_uint64"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_sint32"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_sint64"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_fixed32" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_fixed64" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_sfixed32")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_sfixed64")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_float"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_double"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_bool"    )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_string"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_bytes"   )));
+
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeatedgroup"           )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_nested_message" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_foreign_message")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_import_message" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_nested_enum"    )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_foreign_enum"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_import_enum"    )));
+
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_string_piece")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_cord")));
+
+      Assert.assertEquals(201  , message.getRepeatedField(f("repeated_int32"   ), 0));
+      Assert.assertEquals(202L , message.getRepeatedField(f("repeated_int64"   ), 0));
+      Assert.assertEquals(203  , message.getRepeatedField(f("repeated_uint32"  ), 0));
+      Assert.assertEquals(204L , message.getRepeatedField(f("repeated_uint64"  ), 0));
+      Assert.assertEquals(205  , message.getRepeatedField(f("repeated_sint32"  ), 0));
+      Assert.assertEquals(206L , message.getRepeatedField(f("repeated_sint64"  ), 0));
+      Assert.assertEquals(207  , message.getRepeatedField(f("repeated_fixed32" ), 0));
+      Assert.assertEquals(208L , message.getRepeatedField(f("repeated_fixed64" ), 0));
+      Assert.assertEquals(209  , message.getRepeatedField(f("repeated_sfixed32"), 0));
+      Assert.assertEquals(210L , message.getRepeatedField(f("repeated_sfixed64"), 0));
+      Assert.assertEquals(211F , message.getRepeatedField(f("repeated_float"   ), 0));
+      Assert.assertEquals(212D , message.getRepeatedField(f("repeated_double"  ), 0));
+      Assert.assertEquals(true , message.getRepeatedField(f("repeated_bool"    ), 0));
+      Assert.assertEquals("215", message.getRepeatedField(f("repeated_string"  ), 0));
+      Assert.assertEquals(toBytes("216"), message.getRepeatedField(f("repeated_bytes"), 0));
+
+      Assert.assertEquals(217,
+        ((Message)message.getRepeatedField(f("repeatedgroup"), 0))
+                         .getField(repeatedGroupA));
+      Assert.assertEquals(218,
+        ((Message)message.getRepeatedField(f("repeated_nested_message"), 0))
+                         .getField(nestedB));
+      Assert.assertEquals(219,
+        ((Message)message.getRepeatedField(f("repeated_foreign_message"), 0))
+                         .getField(foreignC));
+      Assert.assertEquals(220,
+        ((Message)message.getRepeatedField(f("repeated_import_message"), 0))
+                         .getField(importD));
+
+      Assert.assertEquals( nestedBar, message.getRepeatedField(f("repeated_nested_enum" ),0));
+      Assert.assertEquals(foreignBar, message.getRepeatedField(f("repeated_foreign_enum"),0));
+      Assert.assertEquals( importBar, message.getRepeatedField(f("repeated_import_enum" ),0));
+
+      Assert.assertEquals("224", message.getRepeatedField(f("repeated_string_piece"), 0));
+      Assert.assertEquals("225", message.getRepeatedField(f("repeated_cord"), 0));
+
+      Assert.assertEquals(301  , message.getRepeatedField(f("repeated_int32"   ), 1));
+      Assert.assertEquals(302L , message.getRepeatedField(f("repeated_int64"   ), 1));
+      Assert.assertEquals(303  , message.getRepeatedField(f("repeated_uint32"  ), 1));
+      Assert.assertEquals(304L , message.getRepeatedField(f("repeated_uint64"  ), 1));
+      Assert.assertEquals(305  , message.getRepeatedField(f("repeated_sint32"  ), 1));
+      Assert.assertEquals(306L , message.getRepeatedField(f("repeated_sint64"  ), 1));
+      Assert.assertEquals(307  , message.getRepeatedField(f("repeated_fixed32" ), 1));
+      Assert.assertEquals(308L , message.getRepeatedField(f("repeated_fixed64" ), 1));
+      Assert.assertEquals(309  , message.getRepeatedField(f("repeated_sfixed32"), 1));
+      Assert.assertEquals(310L , message.getRepeatedField(f("repeated_sfixed64"), 1));
+      Assert.assertEquals(311F , message.getRepeatedField(f("repeated_float"   ), 1));
+      Assert.assertEquals(312D , message.getRepeatedField(f("repeated_double"  ), 1));
+      Assert.assertEquals(false, message.getRepeatedField(f("repeated_bool"    ), 1));
+      Assert.assertEquals("315", message.getRepeatedField(f("repeated_string"  ), 1));
+      Assert.assertEquals(toBytes("316"), message.getRepeatedField(f("repeated_bytes"), 1));
+
+      Assert.assertEquals(317,
+        ((Message)message.getRepeatedField(f("repeatedgroup"), 1))
+                         .getField(repeatedGroupA));
+      Assert.assertEquals(318,
+        ((Message)message.getRepeatedField(f("repeated_nested_message"), 1))
+                         .getField(nestedB));
+      Assert.assertEquals(319,
+        ((Message)message.getRepeatedField(f("repeated_foreign_message"), 1))
+                         .getField(foreignC));
+      Assert.assertEquals(320,
+        ((Message)message.getRepeatedField(f("repeated_import_message"), 1))
+                         .getField(importD));
+
+      Assert.assertEquals( nestedBaz, message.getRepeatedField(f("repeated_nested_enum" ),1));
+      Assert.assertEquals(foreignBaz, message.getRepeatedField(f("repeated_foreign_enum"),1));
+      Assert.assertEquals( importBaz, message.getRepeatedField(f("repeated_import_enum" ),1));
+
+      Assert.assertEquals("324", message.getRepeatedField(f("repeated_string_piece"), 1));
+      Assert.assertEquals("325", message.getRepeatedField(f("repeated_cord"), 1));
+
+      // -----------------------------------------------------------------
+
+      Assert.assertTrue(message.hasField(f("default_int32"   )));
+      Assert.assertTrue(message.hasField(f("default_int64"   )));
+      Assert.assertTrue(message.hasField(f("default_uint32"  )));
+      Assert.assertTrue(message.hasField(f("default_uint64"  )));
+      Assert.assertTrue(message.hasField(f("default_sint32"  )));
+      Assert.assertTrue(message.hasField(f("default_sint64"  )));
+      Assert.assertTrue(message.hasField(f("default_fixed32" )));
+      Assert.assertTrue(message.hasField(f("default_fixed64" )));
+      Assert.assertTrue(message.hasField(f("default_sfixed32")));
+      Assert.assertTrue(message.hasField(f("default_sfixed64")));
+      Assert.assertTrue(message.hasField(f("default_float"   )));
+      Assert.assertTrue(message.hasField(f("default_double"  )));
+      Assert.assertTrue(message.hasField(f("default_bool"    )));
+      Assert.assertTrue(message.hasField(f("default_string"  )));
+      Assert.assertTrue(message.hasField(f("default_bytes"   )));
+
+      Assert.assertTrue(message.hasField(f("default_nested_enum" )));
+      Assert.assertTrue(message.hasField(f("default_foreign_enum")));
+      Assert.assertTrue(message.hasField(f("default_import_enum" )));
+
+      Assert.assertTrue(message.hasField(f("default_string_piece")));
+      Assert.assertTrue(message.hasField(f("default_cord")));
+
+      Assert.assertEquals(401  , message.getField(f("default_int32"   )));
+      Assert.assertEquals(402L , message.getField(f("default_int64"   )));
+      Assert.assertEquals(403  , message.getField(f("default_uint32"  )));
+      Assert.assertEquals(404L , message.getField(f("default_uint64"  )));
+      Assert.assertEquals(405  , message.getField(f("default_sint32"  )));
+      Assert.assertEquals(406L , message.getField(f("default_sint64"  )));
+      Assert.assertEquals(407  , message.getField(f("default_fixed32" )));
+      Assert.assertEquals(408L , message.getField(f("default_fixed64" )));
+      Assert.assertEquals(409  , message.getField(f("default_sfixed32")));
+      Assert.assertEquals(410L , message.getField(f("default_sfixed64")));
+      Assert.assertEquals(411F , message.getField(f("default_float"   )));
+      Assert.assertEquals(412D , message.getField(f("default_double"  )));
+      Assert.assertEquals(false, message.getField(f("default_bool"    )));
+      Assert.assertEquals("415", message.getField(f("default_string"  )));
+      Assert.assertEquals(toBytes("416"), message.getField(f("default_bytes")));
+
+      Assert.assertEquals( nestedFoo, message.getField(f("default_nested_enum" )));
+      Assert.assertEquals(foreignFoo, message.getField(f("default_foreign_enum")));
+      Assert.assertEquals( importFoo, message.getField(f("default_import_enum" )));
+
+      Assert.assertEquals("424", message.getField(f("default_string_piece")));
+      Assert.assertEquals("425", message.getField(f("default_cord")));
+    }
+
+    // -------------------------------------------------------------------
+
+    /**
+     * Assert (using {@code junit.framework.Assert}} that all fields of
+     * {@code message} are cleared, and that getting the fields returns their
+     * default values, using the {@link Message} reflection interface.
+     */
+    public void assertClearViaReflection(Message message) {
+      // has_blah() should initially be false for all optional fields.
+      Assert.assertFalse(message.hasField(f("optional_int32"   )));
+      Assert.assertFalse(message.hasField(f("optional_int64"   )));
+      Assert.assertFalse(message.hasField(f("optional_uint32"  )));
+      Assert.assertFalse(message.hasField(f("optional_uint64"  )));
+      Assert.assertFalse(message.hasField(f("optional_sint32"  )));
+      Assert.assertFalse(message.hasField(f("optional_sint64"  )));
+      Assert.assertFalse(message.hasField(f("optional_fixed32" )));
+      Assert.assertFalse(message.hasField(f("optional_fixed64" )));
+      Assert.assertFalse(message.hasField(f("optional_sfixed32")));
+      Assert.assertFalse(message.hasField(f("optional_sfixed64")));
+      Assert.assertFalse(message.hasField(f("optional_float"   )));
+      Assert.assertFalse(message.hasField(f("optional_double"  )));
+      Assert.assertFalse(message.hasField(f("optional_bool"    )));
+      Assert.assertFalse(message.hasField(f("optional_string"  )));
+      Assert.assertFalse(message.hasField(f("optional_bytes"   )));
+
+      Assert.assertFalse(message.hasField(f("optionalgroup"           )));
+      Assert.assertFalse(message.hasField(f("optional_nested_message" )));
+      Assert.assertFalse(message.hasField(f("optional_foreign_message")));
+      Assert.assertFalse(message.hasField(f("optional_import_message" )));
+
+      Assert.assertFalse(message.hasField(f("optional_nested_enum" )));
+      Assert.assertFalse(message.hasField(f("optional_foreign_enum")));
+      Assert.assertFalse(message.hasField(f("optional_import_enum" )));
+
+      Assert.assertFalse(message.hasField(f("optional_string_piece")));
+      Assert.assertFalse(message.hasField(f("optional_cord")));
+
+      // Optional fields without defaults are set to zero or something like it.
+      Assert.assertEquals(0    , message.getField(f("optional_int32"   )));
+      Assert.assertEquals(0L   , message.getField(f("optional_int64"   )));
+      Assert.assertEquals(0    , message.getField(f("optional_uint32"  )));
+      Assert.assertEquals(0L   , message.getField(f("optional_uint64"  )));
+      Assert.assertEquals(0    , message.getField(f("optional_sint32"  )));
+      Assert.assertEquals(0L   , message.getField(f("optional_sint64"  )));
+      Assert.assertEquals(0    , message.getField(f("optional_fixed32" )));
+      Assert.assertEquals(0L   , message.getField(f("optional_fixed64" )));
+      Assert.assertEquals(0    , message.getField(f("optional_sfixed32")));
+      Assert.assertEquals(0L   , message.getField(f("optional_sfixed64")));
+      Assert.assertEquals(0F   , message.getField(f("optional_float"   )));
+      Assert.assertEquals(0D   , message.getField(f("optional_double"  )));
+      Assert.assertEquals(false, message.getField(f("optional_bool"    )));
+      Assert.assertEquals(""   , message.getField(f("optional_string"  )));
+      Assert.assertEquals(ByteString.EMPTY, message.getField(f("optional_bytes")));
+
+      // Embedded messages should also be clear.
+      Assert.assertFalse(
+        ((Message)message.getField(f("optionalgroup"))).hasField(groupA));
+      Assert.assertFalse(
+        ((Message)message.getField(f("optional_nested_message")))
+                         .hasField(nestedB));
+      Assert.assertFalse(
+        ((Message)message.getField(f("optional_foreign_message")))
+                         .hasField(foreignC));
+      Assert.assertFalse(
+        ((Message)message.getField(f("optional_import_message")))
+                         .hasField(importD));
+
+      Assert.assertEquals(0,
+        ((Message)message.getField(f("optionalgroup"))).getField(groupA));
+      Assert.assertEquals(0,
+        ((Message)message.getField(f("optional_nested_message")))
+                         .getField(nestedB));
+      Assert.assertEquals(0,
+        ((Message)message.getField(f("optional_foreign_message")))
+                         .getField(foreignC));
+      Assert.assertEquals(0,
+        ((Message)message.getField(f("optional_import_message")))
+                         .getField(importD));
+
+      // Enums without defaults are set to the first value in the enum.
+      Assert.assertEquals( nestedFoo, message.getField(f("optional_nested_enum" )));
+      Assert.assertEquals(foreignFoo, message.getField(f("optional_foreign_enum")));
+      Assert.assertEquals( importFoo, message.getField(f("optional_import_enum" )));
+
+      Assert.assertEquals("", message.getField(f("optional_string_piece")));
+      Assert.assertEquals("", message.getField(f("optional_cord")));
+
+      // Repeated fields are empty.
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_int32"   )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_int64"   )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_uint32"  )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_uint64"  )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_sint32"  )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_sint64"  )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_fixed32" )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_fixed64" )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_sfixed32")));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_sfixed64")));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_float"   )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_double"  )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_bool"    )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_string"  )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_bytes"   )));
+
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeatedgroup"           )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_nested_message" )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_foreign_message")));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_import_message" )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_nested_enum"    )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_foreign_enum"   )));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_import_enum"    )));
+
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_string_piece")));
+      Assert.assertEquals(0, message.getRepeatedFieldCount(f("repeated_cord")));
+
+      // has_blah() should also be false for all default fields.
+      Assert.assertFalse(message.hasField(f("default_int32"   )));
+      Assert.assertFalse(message.hasField(f("default_int64"   )));
+      Assert.assertFalse(message.hasField(f("default_uint32"  )));
+      Assert.assertFalse(message.hasField(f("default_uint64"  )));
+      Assert.assertFalse(message.hasField(f("default_sint32"  )));
+      Assert.assertFalse(message.hasField(f("default_sint64"  )));
+      Assert.assertFalse(message.hasField(f("default_fixed32" )));
+      Assert.assertFalse(message.hasField(f("default_fixed64" )));
+      Assert.assertFalse(message.hasField(f("default_sfixed32")));
+      Assert.assertFalse(message.hasField(f("default_sfixed64")));
+      Assert.assertFalse(message.hasField(f("default_float"   )));
+      Assert.assertFalse(message.hasField(f("default_double"  )));
+      Assert.assertFalse(message.hasField(f("default_bool"    )));
+      Assert.assertFalse(message.hasField(f("default_string"  )));
+      Assert.assertFalse(message.hasField(f("default_bytes"   )));
+
+      Assert.assertFalse(message.hasField(f("default_nested_enum" )));
+      Assert.assertFalse(message.hasField(f("default_foreign_enum")));
+      Assert.assertFalse(message.hasField(f("default_import_enum" )));
+
+      Assert.assertFalse(message.hasField(f("default_string_piece" )));
+      Assert.assertFalse(message.hasField(f("default_cord" )));
+
+      // Fields with defaults have their default values (duh).
+      Assert.assertEquals( 41    , message.getField(f("default_int32"   )));
+      Assert.assertEquals( 42L   , message.getField(f("default_int64"   )));
+      Assert.assertEquals( 43    , message.getField(f("default_uint32"  )));
+      Assert.assertEquals( 44L   , message.getField(f("default_uint64"  )));
+      Assert.assertEquals(-45    , message.getField(f("default_sint32"  )));
+      Assert.assertEquals( 46L   , message.getField(f("default_sint64"  )));
+      Assert.assertEquals( 47    , message.getField(f("default_fixed32" )));
+      Assert.assertEquals( 48L   , message.getField(f("default_fixed64" )));
+      Assert.assertEquals( 49    , message.getField(f("default_sfixed32")));
+      Assert.assertEquals(-50L   , message.getField(f("default_sfixed64")));
+      Assert.assertEquals( 51.5F , message.getField(f("default_float"   )));
+      Assert.assertEquals( 52e3D , message.getField(f("default_double"  )));
+      Assert.assertEquals(true   , message.getField(f("default_bool"    )));
+      Assert.assertEquals("hello", message.getField(f("default_string"  )));
+      Assert.assertEquals(toBytes("world"), message.getField(f("default_bytes")));
+
+      Assert.assertEquals( nestedBar, message.getField(f("default_nested_enum" )));
+      Assert.assertEquals(foreignBar, message.getField(f("default_foreign_enum")));
+      Assert.assertEquals( importBar, message.getField(f("default_import_enum" )));
+
+      Assert.assertEquals("abc", message.getField(f("default_string_piece")));
+      Assert.assertEquals("123", message.getField(f("default_cord")));
+    }
+
+    // ---------------------------------------------------------------
+
+    public void assertRepeatedFieldsModifiedViaReflection(Message message) {
+      // ModifyRepeatedFields only sets the second repeated element of each
+      // field.  In addition to verifying this, we also verify that the first
+      // element and size were *not* modified.
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_int32"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_int64"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_uint32"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_uint64"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_sint32"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_sint64"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_fixed32" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_fixed64" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_sfixed32")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_sfixed64")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_float"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_double"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_bool"    )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_string"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_bytes"   )));
+
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeatedgroup"           )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_nested_message" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_foreign_message")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_import_message" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_nested_enum"    )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_foreign_enum"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_import_enum"    )));
+
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_string_piece")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("repeated_cord")));
+
+      Assert.assertEquals(201  , message.getRepeatedField(f("repeated_int32"   ), 0));
+      Assert.assertEquals(202L , message.getRepeatedField(f("repeated_int64"   ), 0));
+      Assert.assertEquals(203  , message.getRepeatedField(f("repeated_uint32"  ), 0));
+      Assert.assertEquals(204L , message.getRepeatedField(f("repeated_uint64"  ), 0));
+      Assert.assertEquals(205  , message.getRepeatedField(f("repeated_sint32"  ), 0));
+      Assert.assertEquals(206L , message.getRepeatedField(f("repeated_sint64"  ), 0));
+      Assert.assertEquals(207  , message.getRepeatedField(f("repeated_fixed32" ), 0));
+      Assert.assertEquals(208L , message.getRepeatedField(f("repeated_fixed64" ), 0));
+      Assert.assertEquals(209  , message.getRepeatedField(f("repeated_sfixed32"), 0));
+      Assert.assertEquals(210L , message.getRepeatedField(f("repeated_sfixed64"), 0));
+      Assert.assertEquals(211F , message.getRepeatedField(f("repeated_float"   ), 0));
+      Assert.assertEquals(212D , message.getRepeatedField(f("repeated_double"  ), 0));
+      Assert.assertEquals(true , message.getRepeatedField(f("repeated_bool"    ), 0));
+      Assert.assertEquals("215", message.getRepeatedField(f("repeated_string"  ), 0));
+      Assert.assertEquals(toBytes("216"), message.getRepeatedField(f("repeated_bytes"), 0));
+
+      Assert.assertEquals(217,
+        ((Message)message.getRepeatedField(f("repeatedgroup"), 0))
+                         .getField(repeatedGroupA));
+      Assert.assertEquals(218,
+        ((Message)message.getRepeatedField(f("repeated_nested_message"), 0))
+                         .getField(nestedB));
+      Assert.assertEquals(219,
+        ((Message)message.getRepeatedField(f("repeated_foreign_message"), 0))
+                         .getField(foreignC));
+      Assert.assertEquals(220,
+        ((Message)message.getRepeatedField(f("repeated_import_message"), 0))
+                         .getField(importD));
+
+      Assert.assertEquals( nestedBar, message.getRepeatedField(f("repeated_nested_enum" ),0));
+      Assert.assertEquals(foreignBar, message.getRepeatedField(f("repeated_foreign_enum"),0));
+      Assert.assertEquals( importBar, message.getRepeatedField(f("repeated_import_enum" ),0));
+
+      Assert.assertEquals("224", message.getRepeatedField(f("repeated_string_piece"), 0));
+      Assert.assertEquals("225", message.getRepeatedField(f("repeated_cord"), 0));
+
+      Assert.assertEquals(501  , message.getRepeatedField(f("repeated_int32"   ), 1));
+      Assert.assertEquals(502L , message.getRepeatedField(f("repeated_int64"   ), 1));
+      Assert.assertEquals(503  , message.getRepeatedField(f("repeated_uint32"  ), 1));
+      Assert.assertEquals(504L , message.getRepeatedField(f("repeated_uint64"  ), 1));
+      Assert.assertEquals(505  , message.getRepeatedField(f("repeated_sint32"  ), 1));
+      Assert.assertEquals(506L , message.getRepeatedField(f("repeated_sint64"  ), 1));
+      Assert.assertEquals(507  , message.getRepeatedField(f("repeated_fixed32" ), 1));
+      Assert.assertEquals(508L , message.getRepeatedField(f("repeated_fixed64" ), 1));
+      Assert.assertEquals(509  , message.getRepeatedField(f("repeated_sfixed32"), 1));
+      Assert.assertEquals(510L , message.getRepeatedField(f("repeated_sfixed64"), 1));
+      Assert.assertEquals(511F , message.getRepeatedField(f("repeated_float"   ), 1));
+      Assert.assertEquals(512D , message.getRepeatedField(f("repeated_double"  ), 1));
+      Assert.assertEquals(true , message.getRepeatedField(f("repeated_bool"    ), 1));
+      Assert.assertEquals("515", message.getRepeatedField(f("repeated_string"  ), 1));
+      Assert.assertEquals(toBytes("516"), message.getRepeatedField(f("repeated_bytes"), 1));
+
+      Assert.assertEquals(517,
+        ((Message)message.getRepeatedField(f("repeatedgroup"), 1))
+                         .getField(repeatedGroupA));
+      Assert.assertEquals(518,
+        ((Message)message.getRepeatedField(f("repeated_nested_message"), 1))
+                         .getField(nestedB));
+      Assert.assertEquals(519,
+        ((Message)message.getRepeatedField(f("repeated_foreign_message"), 1))
+                         .getField(foreignC));
+      Assert.assertEquals(520,
+        ((Message)message.getRepeatedField(f("repeated_import_message"), 1))
+                         .getField(importD));
+
+      Assert.assertEquals( nestedFoo, message.getRepeatedField(f("repeated_nested_enum" ),1));
+      Assert.assertEquals(foreignFoo, message.getRepeatedField(f("repeated_foreign_enum"),1));
+      Assert.assertEquals( importFoo, message.getRepeatedField(f("repeated_import_enum" ),1));
+
+      Assert.assertEquals("524", message.getRepeatedField(f("repeated_string_piece"), 1));
+      Assert.assertEquals("525", message.getRepeatedField(f("repeated_cord"), 1));
+    }
+
+    public void setPackedFieldsViaReflection(Message.Builder message) {
+      message.addRepeatedField(f("packed_int32"   ), 601 );
+      message.addRepeatedField(f("packed_int64"   ), 602L);
+      message.addRepeatedField(f("packed_uint32"  ), 603 );
+      message.addRepeatedField(f("packed_uint64"  ), 604L);
+      message.addRepeatedField(f("packed_sint32"  ), 605 );
+      message.addRepeatedField(f("packed_sint64"  ), 606L);
+      message.addRepeatedField(f("packed_fixed32" ), 607 );
+      message.addRepeatedField(f("packed_fixed64" ), 608L);
+      message.addRepeatedField(f("packed_sfixed32"), 609 );
+      message.addRepeatedField(f("packed_sfixed64"), 610L);
+      message.addRepeatedField(f("packed_float"   ), 611F);
+      message.addRepeatedField(f("packed_double"  ), 612D);
+      message.addRepeatedField(f("packed_bool"    ), true);
+      message.addRepeatedField(f("packed_enum" ),  foreignBar);
+      // Add a second one of each field.
+      message.addRepeatedField(f("packed_int32"   ), 701 );
+      message.addRepeatedField(f("packed_int64"   ), 702L);
+      message.addRepeatedField(f("packed_uint32"  ), 703 );
+      message.addRepeatedField(f("packed_uint64"  ), 704L);
+      message.addRepeatedField(f("packed_sint32"  ), 705 );
+      message.addRepeatedField(f("packed_sint64"  ), 706L);
+      message.addRepeatedField(f("packed_fixed32" ), 707 );
+      message.addRepeatedField(f("packed_fixed64" ), 708L);
+      message.addRepeatedField(f("packed_sfixed32"), 709 );
+      message.addRepeatedField(f("packed_sfixed64"), 710L);
+      message.addRepeatedField(f("packed_float"   ), 711F);
+      message.addRepeatedField(f("packed_double"  ), 712D);
+      message.addRepeatedField(f("packed_bool"    ), false);
+      message.addRepeatedField(f("packed_enum" ),  foreignBaz);
+    }
+
+    public void assertPackedFieldsSetViaReflection(Message message) {
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_int32"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_int64"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_uint32"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_uint64"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_sint32"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_sint64"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_fixed32" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_fixed64" )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_sfixed32")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_sfixed64")));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_float"   )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_double"  )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_bool"    )));
+      Assert.assertEquals(2, message.getRepeatedFieldCount(f("packed_enum"   )));
+      Assert.assertEquals(601  , message.getRepeatedField(f("packed_int32"   ), 0));
+      Assert.assertEquals(602L , message.getRepeatedField(f("packed_int64"   ), 0));
+      Assert.assertEquals(603  , message.getRepeatedField(f("packed_uint32"  ), 0));
+      Assert.assertEquals(604L , message.getRepeatedField(f("packed_uint64"  ), 0));
+      Assert.assertEquals(605  , message.getRepeatedField(f("packed_sint32"  ), 0));
+      Assert.assertEquals(606L , message.getRepeatedField(f("packed_sint64"  ), 0));
+      Assert.assertEquals(607  , message.getRepeatedField(f("packed_fixed32" ), 0));
+      Assert.assertEquals(608L , message.getRepeatedField(f("packed_fixed64" ), 0));
+      Assert.assertEquals(609  , message.getRepeatedField(f("packed_sfixed32"), 0));
+      Assert.assertEquals(610L , message.getRepeatedField(f("packed_sfixed64"), 0));
+      Assert.assertEquals(611F , message.getRepeatedField(f("packed_float"   ), 0));
+      Assert.assertEquals(612D , message.getRepeatedField(f("packed_double"  ), 0));
+      Assert.assertEquals(true , message.getRepeatedField(f("packed_bool"    ), 0));
+      Assert.assertEquals(foreignBar, message.getRepeatedField(f("packed_enum" ),0));
+      Assert.assertEquals(701  , message.getRepeatedField(f("packed_int32"   ), 1));
+      Assert.assertEquals(702L , message.getRepeatedField(f("packed_int64"   ), 1));
+      Assert.assertEquals(703  , message.getRepeatedField(f("packed_uint32"  ), 1));
+      Assert.assertEquals(704L , message.getRepeatedField(f("packed_uint64"  ), 1));
+      Assert.assertEquals(705  , message.getRepeatedField(f("packed_sint32"  ), 1));
+      Assert.assertEquals(706L , message.getRepeatedField(f("packed_sint64"  ), 1));
+      Assert.assertEquals(707  , message.getRepeatedField(f("packed_fixed32" ), 1));
+      Assert.assertEquals(708L , message.getRepeatedField(f("packed_fixed64" ), 1));
+      Assert.assertEquals(709  , message.getRepeatedField(f("packed_sfixed32"), 1));
+      Assert.assertEquals(710L , message.getRepeatedField(f("packed_sfixed64"), 1));
+      Assert.assertEquals(711F , message.getRepeatedField(f("packed_float"   ), 1));
+      Assert.assertEquals(712D , message.getRepeatedField(f("packed_double"  ), 1));
+      Assert.assertEquals(false, message.getRepeatedField(f("packed_bool"    ), 1));
+      Assert.assertEquals(foreignBaz, message.getRepeatedField(f("packed_enum" ),1));
+    }
+
+    /**
+     * Verifies that the reflection setters for the given.Builder object throw a
+     * NullPointerException if they are passed a null value.  Uses Assert to throw an
+     * appropriate assertion failure, if the condition is not verified.
+     */
+    public void assertReflectionSettersRejectNull(Message.Builder builder)
+        throws Exception {
+      try {
+        builder.setField(f("optional_string"), null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+      try {
+        builder.setField(f("optional_bytes"), null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+      try {
+        builder.setField(f("optional_nested_enum"), null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+      try {
+        builder.setField(f("optional_nested_message"),
+                         (TestAllTypes.NestedMessage) null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+      try {
+        builder.setField(f("optional_nested_message"),
+                         (TestAllTypes.NestedMessage.Builder) null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+
+      try {
+        builder.addRepeatedField(f("repeated_string"), null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+      try {
+        builder.addRepeatedField(f("repeated_bytes"), null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+      try {
+        builder.addRepeatedField(f("repeated_nested_enum"), null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+      try {
+        builder.addRepeatedField(f("repeated_nested_message"), null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+    }
+
+    /**
+     * Verifies that the reflection repeated setters for the given Builder object throw a
+     * NullPointerException if they are passed a null value.  Uses Assert to throw an appropriate
+     * assertion failure, if the condition is not verified.
+     */
+    public void assertReflectionRepeatedSettersRejectNull(Message.Builder builder)
+        throws Exception {
+      builder.addRepeatedField(f("repeated_string"), "one");
+      try {
+        builder.setRepeatedField(f("repeated_string"), 0, null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+
+      builder.addRepeatedField(f("repeated_bytes"), toBytes("one"));
+      try {
+        builder.setRepeatedField(f("repeated_bytes"), 0, null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+
+      builder.addRepeatedField(f("repeated_nested_enum"), nestedBaz);
+      try {
+        builder.setRepeatedField(f("repeated_nested_enum"), 0, null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+
+      builder.addRepeatedField(
+          f("repeated_nested_message"),
+          TestAllTypes.NestedMessage.newBuilder().setBb(218).build());
+      try {
+        builder.setRepeatedField(f("repeated_nested_message"), 0, null);
+        Assert.fail("Exception was not thrown");
+      } catch (NullPointerException e) {
+        // We expect this exception.
+      }
+    }
+  }
+
+  /**
+   * @param filePath The path relative to
+   * {@link com.google.testing.util.TestUtil#getDefaultSrcDir}.
+   */
+  public static String readTextFromFile(String filePath) {
+    return readBytesFromFile(filePath).toStringUtf8();
+  }
+
+  private static File getTestDataDir() {
+    // Search each parent directory looking for "src/google/protobuf".
+    File ancestor = new File(".");
+    try {
+      ancestor = ancestor.getCanonicalFile();
+    } catch (IOException e) {
+      throw new RuntimeException(
+        "Couldn't get canonical name of working directory.", e);
+    }
+    while (ancestor != null && ancestor.exists()) {
+      if (new File(ancestor, "src/google/protobuf").exists()) {
+        return new File(ancestor, "src/google/protobuf/testdata");
+      }
+      ancestor = ancestor.getParentFile();
+    }
+
+    throw new RuntimeException(
+      "Could not find golden files.  This test must be run from within the " +
+      "protobuf source package so that it can read test data files from the " +
+      "C++ source tree.");
+  }
+
+  /**
+   * @param filePath The path relative to
+   * {@link com.google.testing.util.TestUtil#getDefaultSrcDir}.
+   */
+  public static ByteString readBytesFromFile(String filename) {
+    File fullPath = new File(getTestDataDir(), filename);
+    try {
+      RandomAccessFile file = new RandomAccessFile(fullPath, "r");
+      byte[] content = new byte[(int) file.length()];
+      file.readFully(content);
+      return ByteString.copyFrom(content);
+    } catch (IOException e) {
+      // Throw a RuntimeException here so that we can call this function from
+      // static initializers.
+      throw new IllegalArgumentException(
+        "Couldn't read file: " + fullPath.getPath(), e);
+    }
+  }
+
+  /**
+   * Get the bytes of the "golden message".  This is a serialized TestAllTypes
+   * with all fields set as they would be by
+   * {@link setAllFields(TestAllTypes.Builder)}, but it is loaded from a file
+   * on disk rather than generated dynamically.  The file is actually generated
+   * by C++ code, so testing against it verifies compatibility with C++.
+   */
+  public static ByteString getGoldenMessage() {
+    if (goldenMessage == null) {
+      goldenMessage = readBytesFromFile("golden_message");
+    }
+    return goldenMessage;
+  }
+  private static ByteString goldenMessage = null;
+
+  /**
+   * Get the bytes of the "golden packed fields message".  This is a serialized
+   * TestPackedTypes with all fields set as they would be by
+   * {@link setPackedFields(TestPackedTypes.Builder)}, but it is loaded from a
+   * file on disk rather than generated dynamically.  The file is actually
+   * generated by C++ code, so testing against it verifies compatibility with
+   * C++.
+   */
+  public static ByteString getGoldenPackedFieldsMessage() {
+    if (goldenPackedFieldsMessage == null) {
+      goldenPackedFieldsMessage =
+          readBytesFromFile("golden_packed_fields_message");
+    }
+    return goldenPackedFieldsMessage;
+  }
+  private static ByteString goldenPackedFieldsMessage = null;
+}
diff --git a/java/src/test/java/com/google/protobuf/TextFormatTest.java b/java/src/test/java/com/google/protobuf/TextFormatTest.java
new file mode 100644
index 0000000..1d73165
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/TextFormatTest.java
@@ -0,0 +1,636 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import com.google.protobuf.Descriptors.FieldDescriptor;
+import protobuf_unittest.UnittestProto.OneString;
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestAllExtensions;
+import protobuf_unittest.UnittestProto.TestEmptyMessage;
+import protobuf_unittest.UnittestProto.TestAllTypes.NestedMessage;
+import protobuf_unittest.UnittestMset.TestMessageSet;
+import protobuf_unittest.UnittestMset.TestMessageSetExtension1;
+import protobuf_unittest.UnittestMset.TestMessageSetExtension2;
+
+import junit.framework.TestCase;
+
+import java.io.StringReader;
+
+/**
+ * Test case for {@link TextFormat}.
+ *
+ * TODO(wenboz): ExtensionTest and rest of text_format_unittest.cc.
+ *
+ * @author wenboz@google.com (Wenbo Zhu)
+ */
+public class TextFormatTest extends TestCase {
+
+  // A basic string with different escapable characters for testing.
+  private final static String kEscapeTestString =
+      "\"A string with ' characters \n and \r newlines and \t tabs and \001 "
+          + "slashes \\";
+
+  // A representation of the above string with all the characters escaped.
+  private final static String kEscapeTestStringEscaped =
+      "\"\\\"A string with \\' characters \\n and \\r newlines "
+          + "and \\t tabs and \\001 slashes \\\\\"";
+
+  private static String allFieldsSetText = TestUtil.readTextFromFile(
+    "text_format_unittest_data.txt");
+  private static String allExtensionsSetText = TestUtil.readTextFromFile(
+    "text_format_unittest_extensions_data.txt");
+
+  private String exoticText =
+    "repeated_int32: -1\n" +
+    "repeated_int32: -2147483648\n" +
+    "repeated_int64: -1\n" +
+    "repeated_int64: -9223372036854775808\n" +
+    "repeated_uint32: 4294967295\n" +
+    "repeated_uint32: 2147483648\n" +
+    "repeated_uint64: 18446744073709551615\n" +
+    "repeated_uint64: 9223372036854775808\n" +
+    "repeated_double: 123.0\n" +
+    "repeated_double: 123.5\n" +
+    "repeated_double: 0.125\n" +
+    "repeated_double: 1.23E17\n" +
+    "repeated_double: 1.235E22\n" +
+    "repeated_double: 1.235E-18\n" +
+    "repeated_double: 123.456789\n" +
+    "repeated_double: Infinity\n" +
+    "repeated_double: -Infinity\n" +
+    "repeated_double: NaN\n" +
+    "repeated_string: \"\\000\\001\\a\\b\\f\\n\\r\\t\\v\\\\\\'\\\"" +
+      "\\341\\210\\264\"\n" +
+    "repeated_bytes: \"\\000\\001\\a\\b\\f\\n\\r\\t\\v\\\\\\'\\\"\\376\"\n";
+
+  private String messageSetText =
+    "[protobuf_unittest.TestMessageSetExtension1] {\n" +
+    "  i: 123\n" +
+    "}\n" +
+    "[protobuf_unittest.TestMessageSetExtension2] {\n" +
+    "  str: \"foo\"\n" +
+    "}\n";
+
+  /** Print TestAllTypes and compare with golden file. */
+  public void testPrintMessage() throws Exception {
+    String javaText = TextFormat.printToString(TestUtil.getAllSet());
+
+    // Java likes to add a trailing ".0" to floats and doubles.  C printf
+    // (with %g format) does not.  Our golden files are used for both
+    // C++ and Java TextFormat classes, so we need to conform.
+    javaText = javaText.replace(".0\n", "\n");
+
+    assertEquals(allFieldsSetText, javaText);
+  }
+
+  /** Print TestAllExtensions and compare with golden file. */
+  public void testPrintExtensions() throws Exception {
+    String javaText = TextFormat.printToString(TestUtil.getAllExtensionsSet());
+
+    // Java likes to add a trailing ".0" to floats and doubles.  C printf
+    // (with %g format) does not.  Our golden files are used for both
+    // C++ and Java TextFormat classes, so we need to conform.
+    javaText = javaText.replace(".0\n", "\n");
+
+    assertEquals(allExtensionsSetText, javaText);
+  }
+
+  public void testPrintUnknownFields() throws Exception {
+    // Test printing of unknown fields in a message.
+
+    TestEmptyMessage message =
+      TestEmptyMessage.newBuilder()
+        .setUnknownFields(
+          UnknownFieldSet.newBuilder()
+            .addField(5,
+              UnknownFieldSet.Field.newBuilder()
+                .addVarint(1)
+                .addFixed32(2)
+                .addFixed64(3)
+                .addLengthDelimited(ByteString.copyFromUtf8("4"))
+                .addGroup(
+                  UnknownFieldSet.newBuilder()
+                    .addField(10,
+                      UnknownFieldSet.Field.newBuilder()
+                        .addVarint(5)
+                        .build())
+                    .build())
+                .build())
+            .addField(8,
+              UnknownFieldSet.Field.newBuilder()
+                .addVarint(1)
+                .addVarint(2)
+                .addVarint(3)
+                .build())
+            .addField(15,
+              UnknownFieldSet.Field.newBuilder()
+                .addVarint(0xABCDEF1234567890L)
+                .addFixed32(0xABCD1234)
+                .addFixed64(0xABCDEF1234567890L)
+                .build())
+            .build())
+        .build();
+
+    assertEquals(
+      "5: 1\n" +
+      "5: 0x00000002\n" +
+      "5: 0x0000000000000003\n" +
+      "5: \"4\"\n" +
+      "5 {\n" +
+      "  10: 5\n" +
+      "}\n" +
+      "8: 1\n" +
+      "8: 2\n" +
+      "8: 3\n" +
+      "15: 12379813812177893520\n" +
+      "15: 0xabcd1234\n" +
+      "15: 0xabcdef1234567890\n",
+      TextFormat.printToString(message));
+  }
+
+  public void testPrintField() throws Exception {
+    final FieldDescriptor dataField =
+      OneString.getDescriptor().findFieldByName("data");
+    assertEquals(
+      "data: \"test data\"\n",
+      TextFormat.printFieldToString(dataField, "test data"));
+
+    final FieldDescriptor optionalField =
+      TestAllTypes.getDescriptor().findFieldByName("optional_nested_message");
+    final Object value = NestedMessage.newBuilder().setBb(42).build();
+    
+    assertEquals(
+      "optional_nested_message {\n  bb: 42\n}\n",
+      TextFormat.printFieldToString(optionalField, value));
+  }
+  
+  /**
+   * Helper to construct a ByteString from a String containing only 8-bit
+   * characters.  The characters are converted directly to bytes, *not*
+   * encoded using UTF-8.
+   */
+  private ByteString bytes(String str) throws Exception {
+    return ByteString.copyFrom(str.getBytes("ISO-8859-1"));
+  }
+
+  /**
+   * Helper to construct a ByteString from a bunch of bytes.  The inputs are
+   * actually ints so that I can use hex notation and not get stupid errors
+   * about precision.
+   */
+  private ByteString bytes(int... bytesAsInts) {
+    byte[] bytes = new byte[bytesAsInts.length];
+    for (int i = 0; i < bytesAsInts.length; i++) {
+      bytes[i] = (byte) bytesAsInts[i];
+    }
+    return ByteString.copyFrom(bytes);
+  }
+
+  public void testPrintExotic() throws Exception {
+    Message message = TestAllTypes.newBuilder()
+      // Signed vs. unsigned numbers.
+      .addRepeatedInt32 (-1)
+      .addRepeatedUint32(-1)
+      .addRepeatedInt64 (-1)
+      .addRepeatedUint64(-1)
+
+      .addRepeatedInt32 (1  << 31)
+      .addRepeatedUint32(1  << 31)
+      .addRepeatedInt64 (1l << 63)
+      .addRepeatedUint64(1l << 63)
+
+      // Floats of various precisions and exponents.
+      .addRepeatedDouble(123)
+      .addRepeatedDouble(123.5)
+      .addRepeatedDouble(0.125)
+      .addRepeatedDouble(123e15)
+      .addRepeatedDouble(123.5e20)
+      .addRepeatedDouble(123.5e-20)
+      .addRepeatedDouble(123.456789)
+      .addRepeatedDouble(Double.POSITIVE_INFINITY)
+      .addRepeatedDouble(Double.NEGATIVE_INFINITY)
+      .addRepeatedDouble(Double.NaN)
+
+      // Strings and bytes that needing escaping.
+      .addRepeatedString("\0\001\007\b\f\n\r\t\013\\\'\"\u1234")
+      .addRepeatedBytes(bytes("\0\001\007\b\f\n\r\t\013\\\'\"\u00fe"))
+      .build();
+
+    assertEquals(exoticText, message.toString());
+  }
+
+  public void testPrintMessageSet() throws Exception {
+    TestMessageSet messageSet =
+      TestMessageSet.newBuilder()
+        .setExtension(
+          TestMessageSetExtension1.messageSetExtension,
+          TestMessageSetExtension1.newBuilder().setI(123).build())
+        .setExtension(
+          TestMessageSetExtension2.messageSetExtension,
+          TestMessageSetExtension2.newBuilder().setStr("foo").build())
+        .build();
+
+    assertEquals(messageSetText, messageSet.toString());
+  }
+
+  // =================================================================
+
+  public void testParse() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TextFormat.merge(allFieldsSetText, builder);
+    TestUtil.assertAllFieldsSet(builder.build());
+  }
+
+  public void testParseReader() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TextFormat.merge(new StringReader(allFieldsSetText), builder);
+    TestUtil.assertAllFieldsSet(builder.build());
+  }
+
+  public void testParseExtensions() throws Exception {
+    TestAllExtensions.Builder builder = TestAllExtensions.newBuilder();
+    TextFormat.merge(allExtensionsSetText,
+                     TestUtil.getExtensionRegistry(),
+                     builder);
+    TestUtil.assertAllExtensionsSet(builder.build());
+  }
+
+  public void testParseCompatibility() throws Exception {
+    String original = "repeated_float: inf\n" +
+                      "repeated_float: -inf\n" +
+                      "repeated_float: nan\n" +
+                      "repeated_float: inff\n" +
+                      "repeated_float: -inff\n" +
+                      "repeated_float: nanf\n" +
+                      "repeated_float: 1.0f\n" +
+                      "repeated_float: infinityf\n" +
+                      "repeated_float: -Infinityf\n" +
+                      "repeated_double: infinity\n" +
+                      "repeated_double: -infinity\n" +
+                      "repeated_double: nan\n";
+    String canonical =  "repeated_float: Infinity\n" +
+                        "repeated_float: -Infinity\n" +
+                        "repeated_float: NaN\n" +
+                        "repeated_float: Infinity\n" +
+                        "repeated_float: -Infinity\n" +
+                        "repeated_float: NaN\n" +
+                        "repeated_float: 1.0\n" +
+                        "repeated_float: Infinity\n" +
+                        "repeated_float: -Infinity\n" +
+                        "repeated_double: Infinity\n" +
+                        "repeated_double: -Infinity\n" +
+                        "repeated_double: NaN\n";
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TextFormat.merge(original, builder);
+    assertEquals(canonical, builder.build().toString());
+  }
+
+  public void testParseExotic() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TextFormat.merge(exoticText, builder);
+
+    // Too lazy to check things individually.  Don't try to debug this
+    // if testPrintExotic() is failing.
+    assertEquals(exoticText, builder.build().toString());
+  }
+
+  public void testParseMessageSet() throws Exception {
+    ExtensionRegistry extensionRegistry = ExtensionRegistry.newInstance();
+    extensionRegistry.add(TestMessageSetExtension1.messageSetExtension);
+    extensionRegistry.add(TestMessageSetExtension2.messageSetExtension);
+
+    TestMessageSet.Builder builder = TestMessageSet.newBuilder();
+    TextFormat.merge(messageSetText, extensionRegistry, builder);
+    TestMessageSet messageSet = builder.build();
+
+    assertTrue(messageSet.hasExtension(
+      TestMessageSetExtension1.messageSetExtension));
+    assertEquals(123, messageSet.getExtension(
+      TestMessageSetExtension1.messageSetExtension).getI());
+    assertTrue(messageSet.hasExtension(
+      TestMessageSetExtension2.messageSetExtension));
+    assertEquals("foo", messageSet.getExtension(
+      TestMessageSetExtension2.messageSetExtension).getStr());
+  }
+
+  public void testParseNumericEnum() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TextFormat.merge("optional_nested_enum: 2", builder);
+    assertEquals(TestAllTypes.NestedEnum.BAR, builder.getOptionalNestedEnum());
+  }
+
+  public void testParseAngleBrackets() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TextFormat.merge("OptionalGroup: < a: 1 >", builder);
+    assertTrue(builder.hasOptionalGroup());
+    assertEquals(1, builder.getOptionalGroup().getA());
+  }
+
+  public void testParseComment() throws Exception {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TextFormat.merge(
+      "# this is a comment\n" +
+      "optional_int32: 1  # another comment\n" +
+      "optional_int64: 2\n" +
+      "# EOF comment", builder);
+    assertEquals(1, builder.getOptionalInt32());
+    assertEquals(2, builder.getOptionalInt64());
+  }
+
+  private void assertParseError(String error, String text) {
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    try {
+      TextFormat.merge(text, TestUtil.getExtensionRegistry(), builder);
+      fail("Expected parse exception.");
+    } catch (TextFormat.ParseException e) {
+      assertEquals(error, e.getMessage());
+    }
+  }
+
+  public void testParseErrors() throws Exception {
+    assertParseError(
+      "1:16: Expected \":\".",
+      "optional_int32 123");
+    assertParseError(
+      "1:23: Expected identifier.",
+      "optional_nested_enum: ?");
+    assertParseError(
+      "1:18: Couldn't parse integer: Number must be positive: -1",
+      "optional_uint32: -1");
+    assertParseError(
+      "1:17: Couldn't parse integer: Number out of range for 32-bit signed " +
+        "integer: 82301481290849012385230157",
+      "optional_int32: 82301481290849012385230157");
+    assertParseError(
+      "1:16: Expected \"true\" or \"false\".",
+      "optional_bool: maybe");
+    assertParseError(
+      "1:18: Expected string.",
+      "optional_string: 123");
+    assertParseError(
+      "1:18: String missing ending quote.",
+      "optional_string: \"ueoauaoe");
+    assertParseError(
+      "1:18: String missing ending quote.",
+      "optional_string: \"ueoauaoe\n" +
+      "optional_int32: 123");
+    assertParseError(
+      "1:18: Invalid escape sequence: '\\z'",
+      "optional_string: \"\\z\"");
+    assertParseError(
+      "1:18: String missing ending quote.",
+      "optional_string: \"ueoauaoe\n" +
+      "optional_int32: 123");
+    assertParseError(
+      "1:2: Extension \"nosuchext\" not found in the ExtensionRegistry.",
+      "[nosuchext]: 123");
+    assertParseError(
+      "1:20: Extension \"protobuf_unittest.optional_int32_extension\" does " +
+        "not extend message type \"protobuf_unittest.TestAllTypes\".",
+      "[protobuf_unittest.optional_int32_extension]: 123");
+    assertParseError(
+      "1:1: Message type \"protobuf_unittest.TestAllTypes\" has no field " +
+        "named \"nosuchfield\".",
+      "nosuchfield: 123");
+    assertParseError(
+      "1:21: Expected \">\".",
+      "OptionalGroup < a: 1");
+    assertParseError(
+      "1:23: Enum type \"protobuf_unittest.TestAllTypes.NestedEnum\" has no " +
+        "value named \"NO_SUCH_VALUE\".",
+      "optional_nested_enum: NO_SUCH_VALUE");
+    assertParseError(
+      "1:23: Enum type \"protobuf_unittest.TestAllTypes.NestedEnum\" has no " +
+        "value with number 123.",
+      "optional_nested_enum: 123");
+
+    // Delimiters must match.
+    assertParseError(
+      "1:22: Expected identifier.",
+      "OptionalGroup < a: 1 }");
+    assertParseError(
+      "1:22: Expected identifier.",
+      "OptionalGroup { a: 1 >");
+  }
+
+  // =================================================================
+
+  public void testEscape() throws Exception {
+    // Escape sequences.
+    assertEquals("\\000\\001\\a\\b\\f\\n\\r\\t\\v\\\\\\'\\\"",
+      TextFormat.escapeBytes(bytes("\0\001\007\b\f\n\r\t\013\\\'\"")));
+    assertEquals("\\000\\001\\a\\b\\f\\n\\r\\t\\v\\\\\\'\\\"",
+      TextFormat.escapeText("\0\001\007\b\f\n\r\t\013\\\'\""));
+    assertEquals(bytes("\0\001\007\b\f\n\r\t\013\\\'\""),
+      TextFormat.unescapeBytes("\\000\\001\\a\\b\\f\\n\\r\\t\\v\\\\\\'\\\""));
+    assertEquals("\0\001\007\b\f\n\r\t\013\\\'\"",
+      TextFormat.unescapeText("\\000\\001\\a\\b\\f\\n\\r\\t\\v\\\\\\'\\\""));
+
+    // Unicode handling.
+    assertEquals("\\341\\210\\264", TextFormat.escapeText("\u1234"));
+    assertEquals("\\341\\210\\264",
+                 TextFormat.escapeBytes(bytes(0xe1, 0x88, 0xb4)));
+    assertEquals("\u1234", TextFormat.unescapeText("\\341\\210\\264"));
+    assertEquals(bytes(0xe1, 0x88, 0xb4),
+                 TextFormat.unescapeBytes("\\341\\210\\264"));
+    assertEquals("\u1234", TextFormat.unescapeText("\\xe1\\x88\\xb4"));
+    assertEquals(bytes(0xe1, 0x88, 0xb4),
+                 TextFormat.unescapeBytes("\\xe1\\x88\\xb4"));
+
+    // Errors.
+    try {
+      TextFormat.unescapeText("\\x");
+      fail("Should have thrown an exception.");
+    } catch (TextFormat.InvalidEscapeSequenceException e) {
+      // success
+    }
+
+    try {
+      TextFormat.unescapeText("\\z");
+      fail("Should have thrown an exception.");
+    } catch (TextFormat.InvalidEscapeSequenceException e) {
+      // success
+    }
+
+    try {
+      TextFormat.unescapeText("\\");
+      fail("Should have thrown an exception.");
+    } catch (TextFormat.InvalidEscapeSequenceException e) {
+      // success
+    }
+  }
+
+  public void testParseInteger() throws Exception {
+    assertEquals(          0, TextFormat.parseInt32(          "0"));
+    assertEquals(          1, TextFormat.parseInt32(          "1"));
+    assertEquals(         -1, TextFormat.parseInt32(         "-1"));
+    assertEquals(      12345, TextFormat.parseInt32(      "12345"));
+    assertEquals(     -12345, TextFormat.parseInt32(     "-12345"));
+    assertEquals( 2147483647, TextFormat.parseInt32( "2147483647"));
+    assertEquals(-2147483648, TextFormat.parseInt32("-2147483648"));
+
+    assertEquals(                0, TextFormat.parseUInt32(         "0"));
+    assertEquals(                1, TextFormat.parseUInt32(         "1"));
+    assertEquals(            12345, TextFormat.parseUInt32(     "12345"));
+    assertEquals(       2147483647, TextFormat.parseUInt32("2147483647"));
+    assertEquals((int) 2147483648L, TextFormat.parseUInt32("2147483648"));
+    assertEquals((int) 4294967295L, TextFormat.parseUInt32("4294967295"));
+
+    assertEquals(          0L, TextFormat.parseInt64(          "0"));
+    assertEquals(          1L, TextFormat.parseInt64(          "1"));
+    assertEquals(         -1L, TextFormat.parseInt64(         "-1"));
+    assertEquals(      12345L, TextFormat.parseInt64(      "12345"));
+    assertEquals(     -12345L, TextFormat.parseInt64(     "-12345"));
+    assertEquals( 2147483647L, TextFormat.parseInt64( "2147483647"));
+    assertEquals(-2147483648L, TextFormat.parseInt64("-2147483648"));
+    assertEquals( 4294967295L, TextFormat.parseInt64( "4294967295"));
+    assertEquals( 4294967296L, TextFormat.parseInt64( "4294967296"));
+    assertEquals(9223372036854775807L,
+                 TextFormat.parseInt64("9223372036854775807"));
+    assertEquals(-9223372036854775808L,
+                 TextFormat.parseInt64("-9223372036854775808"));
+
+    assertEquals(          0L, TextFormat.parseUInt64(          "0"));
+    assertEquals(          1L, TextFormat.parseUInt64(          "1"));
+    assertEquals(      12345L, TextFormat.parseUInt64(      "12345"));
+    assertEquals( 2147483647L, TextFormat.parseUInt64( "2147483647"));
+    assertEquals( 4294967295L, TextFormat.parseUInt64( "4294967295"));
+    assertEquals( 4294967296L, TextFormat.parseUInt64( "4294967296"));
+    assertEquals(9223372036854775807L,
+                 TextFormat.parseUInt64("9223372036854775807"));
+    assertEquals(-9223372036854775808L,
+                 TextFormat.parseUInt64("9223372036854775808"));
+    assertEquals(-1L, TextFormat.parseUInt64("18446744073709551615"));
+
+    // Hex
+    assertEquals(0x1234abcd, TextFormat.parseInt32("0x1234abcd"));
+    assertEquals(-0x1234abcd, TextFormat.parseInt32("-0x1234abcd"));
+    assertEquals(-1, TextFormat.parseUInt64("0xffffffffffffffff"));
+    assertEquals(0x7fffffffffffffffL,
+                 TextFormat.parseInt64("0x7fffffffffffffff"));
+
+    // Octal
+    assertEquals(01234567, TextFormat.parseInt32("01234567"));
+
+    // Out-of-range
+    try {
+      TextFormat.parseInt32("2147483648");
+      fail("Should have thrown an exception.");
+    } catch (NumberFormatException e) {
+      // success
+    }
+
+    try {
+      TextFormat.parseInt32("-2147483649");
+      fail("Should have thrown an exception.");
+    } catch (NumberFormatException e) {
+      // success
+    }
+
+    try {
+      TextFormat.parseUInt32("4294967296");
+      fail("Should have thrown an exception.");
+    } catch (NumberFormatException e) {
+      // success
+    }
+
+    try {
+      TextFormat.parseUInt32("-1");
+      fail("Should have thrown an exception.");
+    } catch (NumberFormatException e) {
+      // success
+    }
+
+    try {
+      TextFormat.parseInt64("9223372036854775808");
+      fail("Should have thrown an exception.");
+    } catch (NumberFormatException e) {
+      // success
+    }
+
+    try {
+      TextFormat.parseInt64("-9223372036854775809");
+      fail("Should have thrown an exception.");
+    } catch (NumberFormatException e) {
+      // success
+    }
+
+    try {
+      TextFormat.parseUInt64("18446744073709551616");
+      fail("Should have thrown an exception.");
+    } catch (NumberFormatException e) {
+      // success
+    }
+
+    try {
+      TextFormat.parseUInt64("-1");
+      fail("Should have thrown an exception.");
+    } catch (NumberFormatException e) {
+      // success
+    }
+
+    // Not a number.
+    try {
+      TextFormat.parseInt32("abcd");
+      fail("Should have thrown an exception.");
+    } catch (NumberFormatException e) {
+      // success
+    }
+  }
+
+  public void testParseLongString() throws Exception {
+    String longText =
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890" +
+      "123456789012345678901234567890123456789012345678901234567890";
+
+    TestAllTypes.Builder builder = TestAllTypes.newBuilder();
+    TextFormat.merge("optional_string: \"" + longText + "\"", builder);
+    assertEquals(longText, builder.getOptionalString());
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/UnknownFieldSetTest.java b/java/src/test/java/com/google/protobuf/UnknownFieldSetTest.java
new file mode 100644
index 0000000..ea088b3
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/UnknownFieldSetTest.java
@@ -0,0 +1,437 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import protobuf_unittest.UnittestProto;
+import protobuf_unittest.UnittestProto.TestAllExtensions;
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestEmptyMessage;
+import protobuf_unittest.UnittestProto.TestEmptyMessageWithExtensions;
+
+import junit.framework.TestCase;
+
+import java.util.Arrays;
+import java.util.Map;
+
+/**
+ * Tests related to unknown field handling.
+ *
+ * @author kenton@google.com (Kenton Varda)
+ */
+public class UnknownFieldSetTest extends TestCase {
+  public void setUp() throws Exception {
+    descriptor = TestAllTypes.getDescriptor();
+    allFields = TestUtil.getAllSet();
+    allFieldsData = allFields.toByteString();
+    emptyMessage = TestEmptyMessage.parseFrom(allFieldsData);
+    unknownFields = emptyMessage.getUnknownFields();
+  }
+
+  UnknownFieldSet.Field getField(String name) {
+    Descriptors.FieldDescriptor field = descriptor.findFieldByName(name);
+    assertNotNull(field);
+    return unknownFields.getField(field.getNumber());
+  }
+
+  // Constructs a protocol buffer which contains fields with all the same
+  // numbers as allFieldsData except that each field is some other wire
+  // type.
+  ByteString getBizarroData() throws Exception {
+    UnknownFieldSet.Builder bizarroFields = UnknownFieldSet.newBuilder();
+
+    UnknownFieldSet.Field varintField =
+      UnknownFieldSet.Field.newBuilder().addVarint(1).build();
+    UnknownFieldSet.Field fixed32Field =
+      UnknownFieldSet.Field.newBuilder().addFixed32(1).build();
+
+    for (Map.Entry<Integer, UnknownFieldSet.Field> entry :
+         unknownFields.asMap().entrySet()) {
+      if (entry.getValue().getVarintList().isEmpty()) {
+        // Original field is not a varint, so use a varint.
+        bizarroFields.addField(entry.getKey(), varintField);
+      } else {
+        // Original field *is* a varint, so use something else.
+        bizarroFields.addField(entry.getKey(), fixed32Field);
+      }
+    }
+
+    return bizarroFields.build().toByteString();
+  }
+
+  Descriptors.Descriptor descriptor;
+  TestAllTypes allFields;
+  ByteString allFieldsData;
+
+  // An empty message that has been parsed from allFieldsData.  So, it has
+  // unknown fields of every type.
+  TestEmptyMessage emptyMessage;
+  UnknownFieldSet unknownFields;
+
+  // =================================================================
+
+  public void testVarint() throws Exception {
+    UnknownFieldSet.Field field = getField("optional_int32");
+    assertEquals(1, field.getVarintList().size());
+    assertEquals(allFields.getOptionalInt32(),
+                 (long) field.getVarintList().get(0));
+  }
+
+  public void testFixed32() throws Exception {
+    UnknownFieldSet.Field field = getField("optional_fixed32");
+    assertEquals(1, field.getFixed32List().size());
+    assertEquals(allFields.getOptionalFixed32(),
+                 (int) field.getFixed32List().get(0));
+  }
+
+  public void testFixed64() throws Exception {
+    UnknownFieldSet.Field field = getField("optional_fixed64");
+    assertEquals(1, field.getFixed64List().size());
+    assertEquals(allFields.getOptionalFixed64(),
+                 (long) field.getFixed64List().get(0));
+  }
+
+  public void testLengthDelimited() throws Exception {
+    UnknownFieldSet.Field field = getField("optional_bytes");
+    assertEquals(1, field.getLengthDelimitedList().size());
+    assertEquals(allFields.getOptionalBytes(),
+                 field.getLengthDelimitedList().get(0));
+  }
+
+  public void testGroup() throws Exception {
+    Descriptors.FieldDescriptor nestedFieldDescriptor =
+      TestAllTypes.OptionalGroup.getDescriptor().findFieldByName("a");
+    assertNotNull(nestedFieldDescriptor);
+
+    UnknownFieldSet.Field field = getField("optionalgroup");
+    assertEquals(1, field.getGroupList().size());
+
+    UnknownFieldSet group = field.getGroupList().get(0);
+    assertEquals(1, group.asMap().size());
+    assertTrue(group.hasField(nestedFieldDescriptor.getNumber()));
+
+    UnknownFieldSet.Field nestedField =
+      group.getField(nestedFieldDescriptor.getNumber());
+    assertEquals(1, nestedField.getVarintList().size());
+    assertEquals(allFields.getOptionalGroup().getA(),
+                 (long) nestedField.getVarintList().get(0));
+  }
+
+  public void testSerialize() throws Exception {
+    // Check that serializing the UnknownFieldSet produces the original data
+    // again.
+    ByteString data = emptyMessage.toByteString();
+    assertEquals(allFieldsData, data);
+  }
+
+  public void testCopyFrom() throws Exception {
+    TestEmptyMessage message =
+      TestEmptyMessage.newBuilder().mergeFrom(emptyMessage).build();
+
+    assertEquals(emptyMessage.toString(), message.toString());
+  }
+
+  public void testMergeFrom() throws Exception {
+    TestEmptyMessage source =
+      TestEmptyMessage.newBuilder()
+        .setUnknownFields(
+          UnknownFieldSet.newBuilder()
+            .addField(2,
+              UnknownFieldSet.Field.newBuilder()
+                .addVarint(2).build())
+            .addField(3,
+              UnknownFieldSet.Field.newBuilder()
+                .addVarint(4).build())
+            .build())
+        .build();
+    TestEmptyMessage destination =
+      TestEmptyMessage.newBuilder()
+        .setUnknownFields(
+          UnknownFieldSet.newBuilder()
+            .addField(1,
+              UnknownFieldSet.Field.newBuilder()
+                .addVarint(1).build())
+            .addField(3,
+              UnknownFieldSet.Field.newBuilder()
+                .addVarint(3).build())
+            .build())
+        .mergeFrom(source)
+        .build();
+
+    assertEquals(
+      "1: 1\n" +
+      "2: 2\n" +
+      "3: 3\n" +
+      "3: 4\n",
+      destination.toString());
+  }
+
+  public void testClear() throws Exception {
+    UnknownFieldSet fields =
+      UnknownFieldSet.newBuilder().mergeFrom(unknownFields).clear().build();
+    assertTrue(fields.asMap().isEmpty());
+  }
+
+  public void testClearMessage() throws Exception {
+    TestEmptyMessage message =
+      TestEmptyMessage.newBuilder().mergeFrom(emptyMessage).clear().build();
+    assertEquals(0, message.getSerializedSize());
+  }
+
+  public void testParseKnownAndUnknown() throws Exception {
+    // Test mixing known and unknown fields when parsing.
+
+    UnknownFieldSet fields =
+      UnknownFieldSet.newBuilder(unknownFields)
+        .addField(123456,
+          UnknownFieldSet.Field.newBuilder().addVarint(654321).build())
+        .build();
+
+    ByteString data = fields.toByteString();
+    TestAllTypes destination = TestAllTypes.parseFrom(data);
+
+    TestUtil.assertAllFieldsSet(destination);
+    assertEquals(1, destination.getUnknownFields().asMap().size());
+
+    UnknownFieldSet.Field field =
+      destination.getUnknownFields().getField(123456);
+    assertEquals(1, field.getVarintList().size());
+    assertEquals(654321, (long) field.getVarintList().get(0));
+  }
+
+  public void testWrongTypeTreatedAsUnknown() throws Exception {
+    // Test that fields of the wrong wire type are treated like unknown fields
+    // when parsing.
+
+    ByteString bizarroData = getBizarroData();
+    TestAllTypes allTypesMessage = TestAllTypes.parseFrom(bizarroData);
+    TestEmptyMessage emptyMessage = TestEmptyMessage.parseFrom(bizarroData);
+
+    // All fields should have been interpreted as unknown, so the debug strings
+    // should be the same.
+    assertEquals(emptyMessage.toString(), allTypesMessage.toString());
+  }
+
+  public void testUnknownExtensions() throws Exception {
+    // Make sure fields are properly parsed to the UnknownFieldSet even when
+    // they are declared as extension numbers.
+
+    TestEmptyMessageWithExtensions message =
+      TestEmptyMessageWithExtensions.parseFrom(allFieldsData);
+
+    assertEquals(unknownFields.asMap().size(),
+                 message.getUnknownFields().asMap().size());
+    assertEquals(allFieldsData, message.toByteString());
+  }
+
+  public void testWrongExtensionTypeTreatedAsUnknown() throws Exception {
+    // Test that fields of the wrong wire type are treated like unknown fields
+    // when parsing extensions.
+
+    ByteString bizarroData = getBizarroData();
+    TestAllExtensions allExtensionsMessage =
+      TestAllExtensions.parseFrom(bizarroData);
+    TestEmptyMessage emptyMessage = TestEmptyMessage.parseFrom(bizarroData);
+
+    // All fields should have been interpreted as unknown, so the debug strings
+    // should be the same.
+    assertEquals(emptyMessage.toString(),
+                 allExtensionsMessage.toString());
+  }
+
+  public void testParseUnknownEnumValue() throws Exception {
+    Descriptors.FieldDescriptor singularField =
+      TestAllTypes.getDescriptor().findFieldByName("optional_nested_enum");
+    Descriptors.FieldDescriptor repeatedField =
+      TestAllTypes.getDescriptor().findFieldByName("repeated_nested_enum");
+    assertNotNull(singularField);
+    assertNotNull(repeatedField);
+
+    ByteString data =
+      UnknownFieldSet.newBuilder()
+        .addField(singularField.getNumber(),
+          UnknownFieldSet.Field.newBuilder()
+            .addVarint(TestAllTypes.NestedEnum.BAR.getNumber())
+            .addVarint(5)   // not valid
+            .build())
+        .addField(repeatedField.getNumber(),
+          UnknownFieldSet.Field.newBuilder()
+            .addVarint(TestAllTypes.NestedEnum.FOO.getNumber())
+            .addVarint(4)   // not valid
+            .addVarint(TestAllTypes.NestedEnum.BAZ.getNumber())
+            .addVarint(6)   // not valid
+            .build())
+        .build()
+        .toByteString();
+
+    {
+      TestAllTypes message = TestAllTypes.parseFrom(data);
+      assertEquals(TestAllTypes.NestedEnum.BAR,
+                   message.getOptionalNestedEnum());
+      assertEquals(
+        Arrays.asList(TestAllTypes.NestedEnum.FOO, TestAllTypes.NestedEnum.BAZ),
+        message.getRepeatedNestedEnumList());
+      assertEquals(Arrays.asList(5L),
+                   message.getUnknownFields()
+                          .getField(singularField.getNumber())
+                          .getVarintList());
+      assertEquals(Arrays.asList(4L, 6L),
+                   message.getUnknownFields()
+                          .getField(repeatedField.getNumber())
+                          .getVarintList());
+    }
+
+    {
+      TestAllExtensions message =
+        TestAllExtensions.parseFrom(data, TestUtil.getExtensionRegistry());
+      assertEquals(TestAllTypes.NestedEnum.BAR,
+        message.getExtension(UnittestProto.optionalNestedEnumExtension));
+      assertEquals(
+        Arrays.asList(TestAllTypes.NestedEnum.FOO, TestAllTypes.NestedEnum.BAZ),
+        message.getExtension(UnittestProto.repeatedNestedEnumExtension));
+      assertEquals(Arrays.asList(5L),
+                   message.getUnknownFields()
+                          .getField(singularField.getNumber())
+                          .getVarintList());
+      assertEquals(Arrays.asList(4L, 6L),
+                   message.getUnknownFields()
+                          .getField(repeatedField.getNumber())
+                          .getVarintList());
+    }
+  }
+
+  public void testLargeVarint() throws Exception {
+    ByteString data =
+      UnknownFieldSet.newBuilder()
+        .addField(1,
+          UnknownFieldSet.Field.newBuilder()
+            .addVarint(0x7FFFFFFFFFFFFFFFL)
+            .build())
+        .build()
+        .toByteString();
+    UnknownFieldSet parsed = UnknownFieldSet.parseFrom(data);
+    UnknownFieldSet.Field field = parsed.getField(1);
+    assertEquals(1, field.getVarintList().size());
+    assertEquals(0x7FFFFFFFFFFFFFFFL, (long)field.getVarintList().get(0));
+  }
+
+  public void testEqualsAndHashCode() {
+    UnknownFieldSet.Field fixed32Field =
+        UnknownFieldSet.Field.newBuilder()
+            .addFixed32(1)
+            .build();
+    UnknownFieldSet.Field fixed64Field =
+        UnknownFieldSet.Field.newBuilder()
+            .addFixed64(1)
+            .build();
+    UnknownFieldSet.Field varIntField =
+        UnknownFieldSet.Field.newBuilder()
+            .addVarint(1)
+            .build();
+    UnknownFieldSet.Field lengthDelimitedField =
+        UnknownFieldSet.Field.newBuilder()
+            .addLengthDelimited(ByteString.EMPTY)
+            .build();
+    UnknownFieldSet.Field groupField =
+        UnknownFieldSet.Field.newBuilder()
+            .addGroup(unknownFields)
+            .build();
+
+    UnknownFieldSet a =
+        UnknownFieldSet.newBuilder()
+            .addField(1, fixed32Field)
+            .build();
+    UnknownFieldSet b =
+        UnknownFieldSet.newBuilder()
+            .addField(1, fixed64Field)
+            .build();
+    UnknownFieldSet c =
+        UnknownFieldSet.newBuilder()
+            .addField(1, varIntField)
+            .build();
+    UnknownFieldSet d =
+        UnknownFieldSet.newBuilder()
+            .addField(1, lengthDelimitedField)
+            .build();
+    UnknownFieldSet e =
+        UnknownFieldSet.newBuilder()
+            .addField(1, groupField)
+            .build();
+
+    checkEqualsIsConsistent(a);
+    checkEqualsIsConsistent(b);
+    checkEqualsIsConsistent(c);
+    checkEqualsIsConsistent(d);
+    checkEqualsIsConsistent(e);
+
+    checkNotEqual(a, b);
+    checkNotEqual(a, c);
+    checkNotEqual(a, d);
+    checkNotEqual(a, e);
+    checkNotEqual(b, c);
+    checkNotEqual(b, d);
+    checkNotEqual(b, e);
+    checkNotEqual(c, d);
+    checkNotEqual(c, e);
+    checkNotEqual(d, e);
+  }
+
+  /**
+   * Asserts that the given field sets are not equal and have different
+   * hash codes.
+   *
+   * @warning It's valid for non-equal objects to have the same hash code, so
+   *   this test is stricter than it needs to be. However, this should happen
+   *   relatively rarely.
+   */
+  private void checkNotEqual(UnknownFieldSet s1, UnknownFieldSet s2) {
+    String equalsError = String.format("%s should not be equal to %s", s1, s2);
+    assertFalse(equalsError, s1.equals(s2));
+    assertFalse(equalsError, s2.equals(s1));
+
+    assertFalse(
+        String.format("%s should have a different hash code from %s", s1, s2),
+        s1.hashCode() == s2.hashCode());
+  }
+
+  /**
+   * Asserts that the given field sets are equal and have identical hash codes.
+   */
+  private void checkEqualsIsConsistent(UnknownFieldSet set) {
+    // Object should be equal to itself.
+    assertEquals(set, set);
+
+    // Object should be equal to a copy of itself.
+    UnknownFieldSet copy = UnknownFieldSet.newBuilder(set).build();
+    assertEquals(set, copy);
+    assertEquals(copy, set);
+    assertEquals(set.hashCode(), copy.hashCode());
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/WireFormatTest.java b/java/src/test/java/com/google/protobuf/WireFormatTest.java
new file mode 100644
index 0000000..bd1c6db
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/WireFormatTest.java
@@ -0,0 +1,402 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package com.google.protobuf;
+
+import junit.framework.TestCase;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+
+import protobuf_unittest.UnittestProto;
+import protobuf_unittest.UnittestProto.TestAllExtensions;
+import protobuf_unittest.UnittestProto.TestAllTypes;
+import protobuf_unittest.UnittestProto.TestFieldOrderings;
+import protobuf_unittest.UnittestProto.TestPackedExtensions;
+import protobuf_unittest.UnittestProto.TestPackedTypes;
+import protobuf_unittest.UnittestMset.TestMessageSet;
+import protobuf_unittest.UnittestMset.RawMessageSet;
+import protobuf_unittest.UnittestMset.TestMessageSetExtension1;
+import protobuf_unittest.UnittestMset.TestMessageSetExtension2;
+import com.google.protobuf.UnittestLite.TestAllExtensionsLite;
+import com.google.protobuf.UnittestLite.TestPackedExtensionsLite;
+
+/**
+ * Tests related to parsing and serialization.
+ *
+ * @author kenton@google.com (Kenton Varda)
+ */
+public class WireFormatTest extends TestCase {
+  public void testSerialization() throws Exception {
+    TestAllTypes message = TestUtil.getAllSet();
+
+    ByteString rawBytes = message.toByteString();
+    assertEquals(rawBytes.size(), message.getSerializedSize());
+
+    TestAllTypes message2 = TestAllTypes.parseFrom(rawBytes);
+
+    TestUtil.assertAllFieldsSet(message2);
+  }
+
+  public void testSerializationPacked() throws Exception {
+    TestPackedTypes message = TestUtil.getPackedSet();
+
+    ByteString rawBytes = message.toByteString();
+    assertEquals(rawBytes.size(), message.getSerializedSize());
+
+    TestPackedTypes message2 = TestPackedTypes.parseFrom(rawBytes);
+
+    TestUtil.assertPackedFieldsSet(message2);
+  }
+
+  public void testSerializeExtensions() throws Exception {
+    // TestAllTypes and TestAllExtensions should have compatible wire formats,
+    // so if we serialize a TestAllExtensions then parse it as TestAllTypes
+    // it should work.
+
+    TestAllExtensions message = TestUtil.getAllExtensionsSet();
+    ByteString rawBytes = message.toByteString();
+    assertEquals(rawBytes.size(), message.getSerializedSize());
+
+    TestAllTypes message2 = TestAllTypes.parseFrom(rawBytes);
+
+    TestUtil.assertAllFieldsSet(message2);
+  }
+
+  public void testSerializePackedExtensions() throws Exception {
+    // TestPackedTypes and TestPackedExtensions should have compatible wire
+    // formats; check that they serialize to the same string.
+    TestPackedExtensions message = TestUtil.getPackedExtensionsSet();
+    ByteString rawBytes = message.toByteString();
+
+    TestPackedTypes message2 = TestUtil.getPackedSet();
+    ByteString rawBytes2 = message2.toByteString();
+
+    assertEquals(rawBytes, rawBytes2);
+  }
+
+  public void testSerializeExtensionsLite() throws Exception {
+    // TestAllTypes and TestAllExtensions should have compatible wire formats,
+    // so if we serialize a TestAllExtensions then parse it as TestAllTypes
+    // it should work.
+
+    TestAllExtensionsLite message = TestUtil.getAllLiteExtensionsSet();
+    ByteString rawBytes = message.toByteString();
+    assertEquals(rawBytes.size(), message.getSerializedSize());
+
+    TestAllTypes message2 = TestAllTypes.parseFrom(rawBytes);
+
+    TestUtil.assertAllFieldsSet(message2);
+  }
+
+  public void testSerializePackedExtensionsLite() throws Exception {
+    // TestPackedTypes and TestPackedExtensions should have compatible wire
+    // formats; check that they serialize to the same string.
+    TestPackedExtensionsLite message = TestUtil.getLitePackedExtensionsSet();
+    ByteString rawBytes = message.toByteString();
+
+    TestPackedTypes message2 = TestUtil.getPackedSet();
+    ByteString rawBytes2 = message2.toByteString();
+
+    assertEquals(rawBytes, rawBytes2);
+  }
+
+  public void testParseExtensions() throws Exception {
+    // TestAllTypes and TestAllExtensions should have compatible wire formats,
+    // so if we serialize a TestAllTypes then parse it as TestAllExtensions
+    // it should work.
+
+    TestAllTypes message = TestUtil.getAllSet();
+    ByteString rawBytes = message.toByteString();
+
+    ExtensionRegistry registry = TestUtil.getExtensionRegistry();
+
+    TestAllExtensions message2 =
+      TestAllExtensions.parseFrom(rawBytes, registry);
+
+    TestUtil.assertAllExtensionsSet(message2);
+  }
+
+  public void testParsePackedExtensions() throws Exception {
+    // Ensure that packed extensions can be properly parsed.
+    TestPackedExtensions message = TestUtil.getPackedExtensionsSet();
+    ByteString rawBytes = message.toByteString();
+
+    ExtensionRegistry registry = TestUtil.getExtensionRegistry();
+
+    TestPackedExtensions message2 =
+        TestPackedExtensions.parseFrom(rawBytes, registry);
+
+    TestUtil.assertPackedExtensionsSet(message2);
+  }
+
+  public void testParseExtensionsLite() throws Exception {
+    // TestAllTypes and TestAllExtensions should have compatible wire formats,
+    // so if we serialize a TestAllTypes then parse it as TestAllExtensions
+    // it should work.
+
+    TestAllTypes message = TestUtil.getAllSet();
+    ByteString rawBytes = message.toByteString();
+
+    ExtensionRegistryLite registry_lite = TestUtil.getExtensionRegistryLite();
+
+    TestAllExtensionsLite message2 =
+      TestAllExtensionsLite.parseFrom(rawBytes, registry_lite);
+
+    TestUtil.assertAllExtensionsSet(message2);
+
+    // Try again using a full extension registry.
+    ExtensionRegistry registry = TestUtil.getExtensionRegistry();
+
+    TestAllExtensionsLite message3 =
+      TestAllExtensionsLite.parseFrom(rawBytes, registry);
+
+    TestUtil.assertAllExtensionsSet(message3);
+  }
+
+  public void testParsePackedExtensionsLite() throws Exception {
+    // Ensure that packed extensions can be properly parsed.
+    TestPackedExtensionsLite message = TestUtil.getLitePackedExtensionsSet();
+    ByteString rawBytes = message.toByteString();
+
+    ExtensionRegistryLite registry = TestUtil.getExtensionRegistryLite();
+
+    TestPackedExtensionsLite message2 =
+        TestPackedExtensionsLite.parseFrom(rawBytes, registry);
+
+    TestUtil.assertPackedExtensionsSet(message2);
+  }
+
+  public void testExtensionsSerializedSize() throws Exception {
+    assertEquals(TestUtil.getAllSet().getSerializedSize(),
+                 TestUtil.getAllExtensionsSet().getSerializedSize());
+  }
+
+  public void testSerializeDelimited() throws Exception {
+    ByteArrayOutputStream output = new ByteArrayOutputStream();
+    TestUtil.getAllSet().writeDelimitedTo(output);
+    output.write(12);
+    TestUtil.getPackedSet().writeDelimitedTo(output);
+    output.write(34);
+
+    ByteArrayInputStream input = new ByteArrayInputStream(output.toByteArray());
+
+    TestUtil.assertAllFieldsSet(TestAllTypes.parseDelimitedFrom(input));
+    assertEquals(12, input.read());
+    TestUtil.assertPackedFieldsSet(TestPackedTypes.parseDelimitedFrom(input));
+    assertEquals(34, input.read());
+    assertEquals(-1, input.read());
+  }
+
+  private void assertFieldsInOrder(ByteString data) throws Exception {
+    CodedInputStream input = data.newCodedInput();
+    int previousTag = 0;
+
+    while (true) {
+      int tag = input.readTag();
+      if (tag == 0) {
+        break;
+      }
+
+      assertTrue(tag > previousTag);
+      previousTag = tag;
+      input.skipField(tag);
+    }
+  }
+
+  public void testInterleavedFieldsAndExtensions() throws Exception {
+    // Tests that fields are written in order even when extension ranges
+    // are interleaved with field numbers.
+    ByteString data =
+      TestFieldOrderings.newBuilder()
+        .setMyInt(1)
+        .setMyString("foo")
+        .setMyFloat(1.0F)
+        .setExtension(UnittestProto.myExtensionInt, 23)
+        .setExtension(UnittestProto.myExtensionString, "bar")
+        .build().toByteString();
+    assertFieldsInOrder(data);
+
+    Descriptors.Descriptor descriptor = TestFieldOrderings.getDescriptor();
+    ByteString dynamic_data =
+      DynamicMessage.newBuilder(TestFieldOrderings.getDescriptor())
+        .setField(descriptor.findFieldByName("my_int"), 1L)
+        .setField(descriptor.findFieldByName("my_string"), "foo")
+        .setField(descriptor.findFieldByName("my_float"), 1.0F)
+        .setField(UnittestProto.myExtensionInt.getDescriptor(), 23)
+        .setField(UnittestProto.myExtensionString.getDescriptor(), "bar")
+        .build().toByteString();
+    assertFieldsInOrder(dynamic_data);
+  }
+
+  private ExtensionRegistry getTestFieldOrderingsRegistry() {
+    ExtensionRegistry result = ExtensionRegistry.newInstance();
+    result.add(UnittestProto.myExtensionInt);
+    result.add(UnittestProto.myExtensionString);
+    return result;
+  }
+
+  public void testParseMultipleExtensionRanges() throws Exception {
+    // Make sure we can parse a message that contains multiple extensions
+    // ranges.
+    TestFieldOrderings source =
+      TestFieldOrderings.newBuilder()
+        .setMyInt(1)
+        .setMyString("foo")
+        .setMyFloat(1.0F)
+        .setExtension(UnittestProto.myExtensionInt, 23)
+        .setExtension(UnittestProto.myExtensionString, "bar")
+        .build();
+    TestFieldOrderings dest =
+      TestFieldOrderings.parseFrom(source.toByteString(),
+                                   getTestFieldOrderingsRegistry());
+    assertEquals(source, dest);
+  }
+
+  public void testParseMultipleExtensionRangesDynamic() throws Exception {
+    // Same as above except with DynamicMessage.
+    Descriptors.Descriptor descriptor = TestFieldOrderings.getDescriptor();
+    DynamicMessage source =
+      DynamicMessage.newBuilder(TestFieldOrderings.getDescriptor())
+        .setField(descriptor.findFieldByName("my_int"), 1L)
+        .setField(descriptor.findFieldByName("my_string"), "foo")
+        .setField(descriptor.findFieldByName("my_float"), 1.0F)
+        .setField(UnittestProto.myExtensionInt.getDescriptor(), 23)
+        .setField(UnittestProto.myExtensionString.getDescriptor(), "bar")
+        .build();
+    DynamicMessage dest =
+      DynamicMessage.parseFrom(descriptor, source.toByteString(),
+                               getTestFieldOrderingsRegistry());
+    assertEquals(source, dest);
+  }
+
+  private static final int UNKNOWN_TYPE_ID = 1550055;
+  private static final int TYPE_ID_1 =
+    TestMessageSetExtension1.getDescriptor().getExtensions().get(0).getNumber();
+  private static final int TYPE_ID_2 =
+    TestMessageSetExtension2.getDescriptor().getExtensions().get(0).getNumber();
+
+  public void testSerializeMessageSet() throws Exception {
+    // Set up a TestMessageSet with two known messages and an unknown one.
+    TestMessageSet messageSet =
+      TestMessageSet.newBuilder()
+        .setExtension(
+          TestMessageSetExtension1.messageSetExtension,
+          TestMessageSetExtension1.newBuilder().setI(123).build())
+        .setExtension(
+          TestMessageSetExtension2.messageSetExtension,
+          TestMessageSetExtension2.newBuilder().setStr("foo").build())
+        .setUnknownFields(
+          UnknownFieldSet.newBuilder()
+            .addField(UNKNOWN_TYPE_ID,
+              UnknownFieldSet.Field.newBuilder()
+                .addLengthDelimited(ByteString.copyFromUtf8("bar"))
+                .build())
+            .build())
+        .build();
+
+    ByteString data = messageSet.toByteString();
+
+    // Parse back using RawMessageSet and check the contents.
+    RawMessageSet raw = RawMessageSet.parseFrom(data);
+
+    assertTrue(raw.getUnknownFields().asMap().isEmpty());
+
+    assertEquals(3, raw.getItemCount());
+    assertEquals(TYPE_ID_1, raw.getItem(0).getTypeId());
+    assertEquals(TYPE_ID_2, raw.getItem(1).getTypeId());
+    assertEquals(UNKNOWN_TYPE_ID, raw.getItem(2).getTypeId());
+
+    TestMessageSetExtension1 message1 =
+      TestMessageSetExtension1.parseFrom(
+        raw.getItem(0).getMessage().toByteArray());
+    assertEquals(123, message1.getI());
+
+    TestMessageSetExtension2 message2 =
+      TestMessageSetExtension2.parseFrom(
+        raw.getItem(1).getMessage().toByteArray());
+    assertEquals("foo", message2.getStr());
+
+    assertEquals("bar", raw.getItem(2).getMessage().toStringUtf8());
+  }
+
+  public void testParseMessageSet() throws Exception {
+    ExtensionRegistry extensionRegistry = ExtensionRegistry.newInstance();
+    extensionRegistry.add(TestMessageSetExtension1.messageSetExtension);
+    extensionRegistry.add(TestMessageSetExtension2.messageSetExtension);
+
+    // Set up a RawMessageSet with two known messages and an unknown one.
+    RawMessageSet raw =
+      RawMessageSet.newBuilder()
+        .addItem(
+          RawMessageSet.Item.newBuilder()
+            .setTypeId(TYPE_ID_1)
+            .setMessage(
+              TestMessageSetExtension1.newBuilder()
+                .setI(123)
+                .build().toByteString())
+            .build())
+        .addItem(
+          RawMessageSet.Item.newBuilder()
+            .setTypeId(TYPE_ID_2)
+            .setMessage(
+              TestMessageSetExtension2.newBuilder()
+                .setStr("foo")
+                .build().toByteString())
+            .build())
+        .addItem(
+          RawMessageSet.Item.newBuilder()
+            .setTypeId(UNKNOWN_TYPE_ID)
+            .setMessage(ByteString.copyFromUtf8("bar"))
+            .build())
+        .build();
+
+    ByteString data = raw.toByteString();
+
+    // Parse as a TestMessageSet and check the contents.
+    TestMessageSet messageSet =
+      TestMessageSet.parseFrom(data, extensionRegistry);
+
+    assertEquals(123, messageSet.getExtension(
+      TestMessageSetExtension1.messageSetExtension).getI());
+    assertEquals("foo", messageSet.getExtension(
+      TestMessageSetExtension2.messageSetExtension).getStr());
+
+    // Check for unknown field with type LENGTH_DELIMITED,
+    //   number UNKNOWN_TYPE_ID, and contents "bar".
+    UnknownFieldSet unknownFields = messageSet.getUnknownFields();
+    assertEquals(1, unknownFields.asMap().size());
+    assertTrue(unknownFields.hasField(UNKNOWN_TYPE_ID));
+
+    UnknownFieldSet.Field field = unknownFields.getField(UNKNOWN_TYPE_ID);
+    assertEquals(1, field.getLengthDelimitedList().size());
+    assertEquals("bar", field.getLengthDelimitedList().get(0).toStringUtf8());
+  }
+}
diff --git a/java/src/test/java/com/google/protobuf/multiple_files_test.proto b/java/src/test/java/com/google/protobuf/multiple_files_test.proto
new file mode 100644
index 0000000..060f159
--- /dev/null
+++ b/java/src/test/java/com/google/protobuf/multiple_files_test.proto
@@ -0,0 +1,67 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// http://code.google.com/p/protobuf/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Author: kenton@google.com (Kenton Varda)
+//
+// A proto file which tests the java_multiple_files option.
+
+
+import "google/protobuf/unittest.proto";
+
+package protobuf_unittest;
+
+option java_multiple_files = true;
+option java_outer_classname = "MultipleFilesTestProto";
+
+message MessageWithNoOuter {
+  message NestedMessage {
+    optional int32 i = 1;
+  }
+  enum NestedEnum {
+    BAZ = 3;
+  }
+  optional NestedMessage nested = 1;
+  repeated TestAllTypes foreign = 2;
+  optional NestedEnum nested_enum = 3;
+  optional EnumWithNoOuter foreign_enum = 4;
+}
+
+enum EnumWithNoOuter {
+  FOO = 1;
+  BAR = 2;
+}
+
+service ServiceWithNoOuter {
+  rpc Foo(MessageWithNoOuter) returns(TestAllTypes);
+}
+
+extend TestAllExtensions {
+  optional int32 extension_with_outer = 1234567;
+}