Support generation of Parcelable nano messages.

This CL adds the "parcelable_messages" option. When enabled, all
generated message classes will conform to the Android Parcelable
contract. This is achieved by introducing a new parent class for
generated classes which implements the required functionality.

Since the store_unknown_fields option also makes use of a superclass,
ExtendableMessageNano, we have two versions of the new Parcelable
superclass: one extending MessageNano, and one extending
ExtendableMessageNano. These classes are otherwise identical.

As these classes depend on Android framework jars, they are not
included in the host .jar build of the nanoproto library.

Finally, add a test suite for running tests of Android-specific
functionality, as this cannot be done on a desktop JVM.

Change-Id: Icc2a257f03317e947f7078dbb9857c3286857497

6 files changed, 355 insertions, 1 deletions

diff --git a/java/README.txt b/java/README.txt
index f922c4b..c693313 100644
--- a/java/README.txt
+++ b/java/README.txt
@@ -476,6 +476,7 @@ java_nano_generate_has -> true or false [DEPRECATED]
 optional_field_style   -> default or accessors
 enum_style             -> c or java
 ignore_services        -> true or false
+parcelable_messages    -> true or false
 
 java_package:
 java_outer_classname:
@@ -588,6 +589,9 @@ ignore_services={true,false} (default: false)
   it will generate a compilation error. If this flag is set to true,
   services will be silently ignored, instead.
 
+parcelable_messages={true,false} (default: false)
+  Android-specific option to generate Parcelable messages.
+
 
 To use nano protobufs within the Android repo:
 
@@ -638,8 +642,13 @@ Please run the following steps to test:
 - cd ../../..
 - . build/envsetup.sh
 - lunch 1
-- "make -j12 aprotoc libprotobuf-java-2.3.0-nano aprotoc-test-nano-params" and
+- "make -j12 aprotoc libprotobuf-java-2.3.0-nano aprotoc-test-nano-params NanoAndroidTest" and
   check for build errors.
+- Plug in an Android device or start an emulator.
+- adb install -r out/target/product/generic/data/app/NanoAndroidTest.apk
+- Run:
+  "adb shell am instrument -w com.google.protobuf.nano.test/android.test.InstrumentationTestRunner"
+  and verify all tests pass.
 - repo sync -c -j256
 - "make -j12" and check for build errors
 
diff --git a/java/src/device/main/java/com/google/protobuf/nano/android/ParcelableExtendableMessageNano.java b/java/src/device/main/java/com/google/protobuf/nano/android/ParcelableExtendableMessageNano.java
new file mode 100644
index 0000000..f3b82ed
--- /dev/null
+++ b/java/src/device/main/java/com/google/protobuf/nano/android/ParcelableExtendableMessageNano.java
@@ -0,0 +1,69 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2014 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.nano.android;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import com.google.protobuf.nano.ExtendableMessageNano;
+
+/**
+ * Base class for Parcelable Protocol Buffer messages which also need to store unknown
+ * fields, such as extensions.
+ */
+public abstract class ParcelableExtendableMessageNano<M extends ExtendableMessageNano<M>>
+        extends ExtendableMessageNano<M> implements Parcelable {
+
+    // Used by Parcelable
+    @SuppressWarnings({"unused"})
+    public static final Creator<ParcelableExtendableMessageNano<?>> CREATOR =
+            new Creator<ParcelableExtendableMessageNano<?>>() {
+        @Override
+        public ParcelableExtendableMessageNano<?> createFromParcel(Parcel in) {
+            return ParcelingUtil.createFromParcel(in);
+        }
+
+        @Override
+        public ParcelableExtendableMessageNano<?>[] newArray(int size) {
+            return new ParcelableExtendableMessageNano<?>[size];
+        }
+    };
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel out, int flags) {
+        ParcelingUtil.writeToParcel(getClass(), this, out);
+    }
+}
diff --git a/java/src/device/main/java/com/google/protobuf/nano/android/ParcelableMessageNano.java b/java/src/device/main/java/com/google/protobuf/nano/android/ParcelableMessageNano.java
new file mode 100644
index 0000000..b07f1d6
--- /dev/null
+++ b/java/src/device/main/java/com/google/protobuf/nano/android/ParcelableMessageNano.java
@@ -0,0 +1,67 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2014 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.nano.android;
+
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import com.google.protobuf.nano.MessageNano;
+
+/**
+ * Base class for Parcelable Protocol Buffer messages.
+ */
+public abstract class ParcelableMessageNano extends MessageNano implements Parcelable {
+
+    // Used by Parcelable
+    @SuppressWarnings("unused")
+    public static final Creator<ParcelableMessageNano> CREATOR =
+            new Creator<ParcelableMessageNano>() {
+        @Override
+        public ParcelableMessageNano createFromParcel(Parcel in) {
+            return ParcelingUtil.createFromParcel(in);
+        }
+
+        @Override
+        public ParcelableMessageNano[] newArray(int size) {
+            return new ParcelableMessageNano[size];
+        }
+    };
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(Parcel out, int flags) {
+        ParcelingUtil.writeToParcel(getClass(), this, out);
+    }
+}
diff --git a/java/src/device/main/java/com/google/protobuf/nano/android/ParcelingUtil.java b/java/src/device/main/java/com/google/protobuf/nano/android/ParcelingUtil.java
new file mode 100644
index 0000000..1eb84ee
--- /dev/null
+++ b/java/src/device/main/java/com/google/protobuf/nano/android/ParcelingUtil.java
@@ -0,0 +1,72 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2014 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.nano.android;
+
+import android.os.Parcel;
+import android.util.Log;
+
+import com.google.protobuf.nano.InvalidProtocolBufferNanoException;
+import com.google.protobuf.nano.MessageNano;
+
+final class ParcelingUtil {
+    private static final String TAG = "ParcelingUtil";
+
+    @SuppressWarnings("unchecked")
+    static <T extends MessageNano> T createFromParcel(Parcel in) {
+        String className = in.readString();
+        byte[] data = in.createByteArray();
+
+        T proto = null;
+
+        try {
+            Class<?> clazz = Class.forName(className);
+            Object instance = clazz.newInstance();
+            proto = (T) instance;
+            MessageNano.mergeFrom(proto, data);
+        } catch (ClassNotFoundException e) {
+            Log.e(TAG, "Exception trying to create proto from parcel", e);
+        } catch (IllegalAccessException e) {
+            Log.e(TAG, "Exception trying to create proto from parcel", e);
+        } catch (InstantiationException e) {
+            Log.e(TAG, "Exception trying to create proto from parcel", e);
+        } catch (InvalidProtocolBufferNanoException e) {
+            Log.e(TAG, "Exception trying to create proto from parcel", e);
+        }
+
+        return proto;
+    }
+
+    static <T extends MessageNano> void writeToParcel(Class<T> clazz, MessageNano message,
+            Parcel out) {
+        out.writeString(clazz.getName());
+        out.writeByteArray(MessageNano.toByteArray(message));
+    }
+}
diff --git a/java/src/device/test/AndroidManifest.xml b/java/src/device/test/AndroidManifest.xml
new file mode 100644
index 0000000..cc54e57
--- /dev/null
+++ b/java/src/device/test/AndroidManifest.xml
@@ -0,0 +1,50 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  Protocol Buffers - Google's data interchange format
+  Copyright 2014 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.
+-->
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.google.protobuf.nano.test"
+    android:versionCode="1"
+    android:versionName="1.0">
+
+    <uses-sdk
+        android:minSdkVersion="8"
+        android:targetSdkVersion="8" />
+
+    <instrumentation
+        android:name="android.test.InstrumentationTestRunner"
+        android:targetPackage="com.google.protobuf.nano.test" />
+
+    <application>
+        <uses-library android:name="android.test.runner" />
+    </application>
+
+</manifest>
diff --git a/java/src/device/test/java/com/google/protobuf/nano/NanoAndroidTest.java b/java/src/device/test/java/com/google/protobuf/nano/NanoAndroidTest.java
new file mode 100644
index 0000000..7092485
--- /dev/null
+++ b/java/src/device/test/java/com/google/protobuf/nano/NanoAndroidTest.java
@@ -0,0 +1,87 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2014 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.nano;
+
+import android.os.Parcel;
+
+import com.google.protobuf.nano.Extensions.ContainerMessage;
+import com.google.protobuf.nano.Extensions.ExtendableMessage;
+import com.google.protobuf.nano.UnittestSimpleNano.SimpleMessageNano;
+import com.google.protobuf.nano.UnittestSimpleNano.SimpleMessageNano.NestedMessage;
+
+import junit.framework.TestCase;
+
+public class NanoAndroidTest extends TestCase {
+    public void testParceling() {
+        SimpleMessageNano message = new SimpleMessageNano();
+        message.d = 54321;
+        message.nestedMsg = new NestedMessage();
+        message.nestedMsg.bb = 12345;
+        message.defaultNestedEnum = SimpleMessageNano.FOO;
+
+        Parcel parcel = null;
+        try {
+            parcel = Parcel.obtain();
+            parcel.writeParcelable(message, 0);
+            parcel.setDataPosition(0);
+            message = parcel.readParcelable(getClass().getClassLoader());
+        } finally {
+            if (parcel != null) {
+                parcel.recycle();
+            }
+        }
+
+        assertEquals(54321, message.d);
+        assertEquals(12345, message.nestedMsg.bb);
+        assertEquals(SimpleMessageNano.FOO, message.defaultNestedEnum);
+    }
+
+    public void testExtendableParceling() {
+        ExtendableMessage message = new ExtendableMessage();
+        message.field = 12345;
+        message.setExtension(ContainerMessage.anotherThing, true);
+
+        Parcel parcel = null;
+        try {
+            parcel = Parcel.obtain();
+            parcel.writeParcelable(message, 0);
+            parcel.setDataPosition(0);
+            message = parcel.readParcelable(getClass().getClassLoader());
+        } finally {
+            if (parcel != null) {
+                parcel.recycle();
+            }
+        }
+
+        assertEquals(12345, message.field);
+        assertTrue((boolean) message.getExtension(ContainerMessage.anotherThing));
+    }
+}