Add lint recycle detector

This lint check looks for missing recycle() calls on resources such as
TypedArrays, MotionEvents, and Messages.

41140 New Lint Check: Check Recycling VelocityTracker
41138 New Lint Check: Check Recycling Message
41137 New Lint Check: Check Recycling MotionEvent
41136 New Lint Check: Check Recycling TypedArray

In addition, it also flags cases where a method is called on a resource
after the resource has been recycled.

Change-Id: Ia06a1779519971d5459f1cd98914a6aededc4b83

5 files changed, 244 insertions, 9 deletions

diff --git a/lint/cli/.classpath b/lint/cli/.classpath
index ade4f41..3278842 100644
--- a/lint/cli/.classpath
+++ b/lint/cli/.classpath
@@ -5,11 +5,11 @@
 	<classpathentry combineaccessrules="false" kind="src" path="/common"/>
 	<classpathentry combineaccessrules="false" kind="src" path="/lint-api"/>
 	<classpathentry combineaccessrules="false" kind="src" path="/lint-checks"/>
-	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src.zip"/>
-	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-tree-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src.zip"/>
-	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-analysis-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src.zip"/>
-	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/guava-tools/guava-13.0.1.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/guava-tools/src.zip"/>
-	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/lombok-ast/lombok-ast-0.2.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/lombok-ast/src.zip"/>
+	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src-4.0.zip"/>
+	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-tree-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src-4.0.zip"/>
+	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-analysis-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src-4.0.zip"/>
+	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/guava-tools/guava-13.0.1.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/guava-tools/src-4.0.zip"/>
+	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/lombok-ast/lombok-ast-0.2.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/lombok-ast/src-4.0.zip"/>
 	<classpathentry combineaccessrules="false" kind="src" path="/SdkLib"/>
 	<classpathentry kind="output" path="bin"/>
 </classpath>
diff --git a/lint/cli/src/test/.classpath b/lint/cli/src/test/.classpath
index 178cd8c..e79b65f 100644
--- a/lint/cli/src/test/.classpath
+++ b/lint/cli/src/test/.classpath
@@ -7,10 +7,10 @@
 	<classpathentry combineaccessrules="false" kind="src" path="/lint-api"/>
 	<classpathentry combineaccessrules="false" kind="src" path="/lint-checks"/>
 	<classpathentry combineaccessrules="false" kind="src" path="/lint-cli"/>
-	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src.zip"/>
-	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-tree-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src.zip"/>
-	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/guava-tools/guava-13.0.1.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/guava-tools/src.zip"/>
-	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/lombok-ast/lombok-ast-0.2.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/lombok-ast/src.zip"/>
+	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src-4.0.zip"/>
+	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/asm-tools/asm-tree-4.0.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/asm-tools/src-4.0.zip"/>
+	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/guava-tools/guava-13.0.1.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/guava-tools/src-4.0.zip"/>
+	<classpathentry kind="var" path="ANDROID_SRC/prebuilts/tools/common/lombok-ast/lombok-ast-0.2.jar" sourcepath="/ANDROID_SRC/prebuilts/tools/common/lombok-ast/src-4.0.zip"/>
 	<classpathentry combineaccessrules="false" kind="src" path="/layoutlib_api"/>
 	<classpathentry combineaccessrules="false" kind="src" path="/common"/>
 	<classpathentry combineaccessrules="false" kind="src" path="/testutils"/>
diff --git a/lint/cli/src/test/java/com/android/tools/lint/checks/RecycleDetectorTest.java b/lint/cli/src/test/java/com/android/tools/lint/checks/RecycleDetectorTest.java
new file mode 100644
index 0000000..ebef046
--- /dev/null
+++ b/lint/cli/src/test/java/com/android/tools/lint/checks/RecycleDetectorTest.java
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.tools.lint.checks;
+
+import com.android.tools.lint.detector.api.Detector;
+
+@SuppressWarnings("javadoc")
+public class RecycleDetectorTest extends AbstractCheckTest {
+    @Override
+    protected Detector getDetector() {
+        return new RecycleDetector();
+    }
+
+    public void test() throws Exception {
+        assertEquals(
+            "src/test/pkg/RecycleTest.java:56: Warning: This TypedArray should be recycled after use with #recycle() [Recycle]\n" +
+            "  final TypedArray a = getContext().obtainStyledAttributes(attrs,\n" +
+            "                                    ~~~~~~~~~~~~~~~~~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:63: Warning: This TypedArray should be recycled after use with #recycle() [Recycle]\n" +
+            "  final TypedArray a = getContext().obtainStyledAttributes(new int[0]);\n" +
+            "                                    ~~~~~~~~~~~~~~~~~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:79: Warning: This VelocityTracker should be recycled after use with #recycle() [Recycle]\n" +
+            "  VelocityTracker tracker = VelocityTracker.obtain();\n" +
+            "                                            ~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:85: Warning: This Message should be recycled after use with #recycle() [Recycle]\n" +
+            "  Message message1 = getHandler().obtainMessage();\n" +
+            "                                  ~~~~~~~~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:86: Warning: This Message should be recycled after use with #recycle() [Recycle]\n" +
+            "  Message message2 = Message.obtain();\n" +
+            "                             ~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:92: Warning: This MotionEvent should be recycled after use with #recycle() [Recycle]\n" +
+            "  MotionEvent event1 = MotionEvent.obtain(null);\n" +
+            "                                   ~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:93: Warning: This MotionEvent should be recycled after use with #recycle() [Recycle]\n" +
+            "  MotionEvent event2 = MotionEvent.obtainNoHistory(null);\n" +
+            "                                   ~~~~~~~~~~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:98: Warning: This MotionEvent should be recycled after use with #recycle() [Recycle]\n" +
+            "  MotionEvent event2 = MotionEvent.obtainNoHistory(null); // Not recycled\n" +
+            "                                   ~~~~~~~~~~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:103: Warning: This MotionEvent should be recycled after use with #recycle() [Recycle]\n" +
+            "  MotionEvent event1 = MotionEvent.obtain(null);  // Not recycled\n" +
+            "                                   ~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:113: Warning: This MotionEvent has already been recycled [Recycle]\n" +
+            "  int contents2 = event1.describeContents(); // BAD, after recycle\n" +
+            "                         ~~~~~~~~~~~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:117: Warning: This TypedArray has already been recycled [Recycle]\n" +
+            "  example = a.getString(R.styleable.MyView_exampleString); // BAD, after recycle\n" +
+            "              ~~~~~~~~~\n" +
+            "src/test/pkg/RecycleTest.java:129: Warning: This Parcel should be recycled after use with #recycle() [Recycle]\n" +
+            "  Parcel myparcel = Parcel.obtain();\n" +
+            "                           ~~~~~~\n" +
+            "0 errors, 12 warnings\n",
+
+            lintProject(
+                "apicheck/classpath=>.classpath",
+                "apicheck/minsdk4.xml=>AndroidManifest.xml",
+                "project.properties1=>project.properties",
+                "bytecode/RecycleTest.java.txt=>src/test/pkg/RecycleTest.java",
+                "bytecode/RecycleTest.class.data=>bin/classes/test/pkg/RecycleTest.class"
+            ));
+    }
+}
diff --git a/lint/cli/src/test/java/com/android/tools/lint/checks/data/bytecode/RecycleTest.class.data b/lint/cli/src/test/java/com/android/tools/lint/checks/data/bytecode/RecycleTest.class.data
new file mode 100644
index 0000000..3bdc829
--- /dev/null
+++ b/lint/cli/src/test/java/com/android/tools/lint/checks/data/bytecode/RecycleTest.class.data
diff --git a/lint/cli/src/test/java/com/android/tools/lint/checks/data/bytecode/RecycleTest.java.txt b/lint/cli/src/test/java/com/android/tools/lint/checks/data/bytecode/RecycleTest.java.txt
new file mode 100644
index 0000000..2a026f2
--- /dev/null
+++ b/lint/cli/src/test/java/com/android/tools/lint/checks/data/bytecode/RecycleTest.java.txt
@@ -0,0 +1,159 @@
+package test.pkg;
+
+import com.unit.test.R;
+
+import android.annotation.SuppressLint;
+import android.content.Context;
+import android.content.res.TypedArray;
+import android.os.Message;
+import android.os.Parcel;
+import android.util.AttributeSet;
+import android.view.MotionEvent;
+import android.view.VelocityTracker;
+import android.view.View;
+
+@SuppressWarnings("unused")
+public class RecycleTest extends View {
+	// ---- Check recycling TypedArrays ----
+
+	public RecycleTest(Context context, AttributeSet attrs, int defStyle) {
+		super(context, attrs, defStyle);
+	}
+
+	public void ok1(AttributeSet attrs, int defStyle) {
+		final TypedArray a = getContext().obtainStyledAttributes(attrs,
+				R.styleable.MyView, defStyle, 0);
+		String example = a.getString(R.styleable.MyView_exampleString);
+		a.recycle();
+	}
+
+	public void ok2(AttributeSet attrs, int defStyle) {
+		final TypedArray a = getContext().obtainStyledAttributes(attrs,
+				R.styleable.MyView, defStyle, 0);
+		String example = a.getString(R.styleable.MyView_exampleString);
+		// If there's complicated logic, don't flag
+		if (something()) {
+			a.recycle();
+		}
+	}
+
+	public TypedArray ok3(AttributeSet attrs, int defStyle) {
+		// Value passes out of method: don't flag, caller might be recycling
+		return getContext().obtainStyledAttributes(attrs, R.styleable.MyView,
+				defStyle, 0);
+	}
+
+	private TypedArray myref;
+
+	public void ok4(AttributeSet attrs, int defStyle) {
+		// Value stored in a field: might be recycled later
+		TypedArray ref = getContext().obtainStyledAttributes(attrs,
+				R.styleable.MyView, defStyle, 0);
+		myref = ref;
+	}
+
+	public void wrong1(AttributeSet attrs, int defStyle) {
+		final TypedArray a = getContext().obtainStyledAttributes(attrs,
+				R.styleable.MyView, defStyle, 0);
+		String example = a.getString(R.styleable.MyView_exampleString);
+		// a.recycle();
+	}
+
+	public void wrong2(AttributeSet attrs, int defStyle) {
+		final TypedArray a = getContext().obtainStyledAttributes(new int[0]);
+		// a.recycle();
+	}
+
+	public void unknown(AttributeSet attrs, int defStyle) {
+		final TypedArray a = getContext().obtainStyledAttributes(attrs,
+				R.styleable.MyView, defStyle, 0);
+		// We don't know what this method is (usually it will be in a different
+		// class)
+		// so don't flag it; it might recycle
+		handle(a);
+	}
+
+	// ---- Check recycling VelocityTracker ----
+
+	public void tracker() {
+		VelocityTracker tracker = VelocityTracker.obtain();
+	}
+
+	// ---- Check recycling Message ----
+
+	public void message() {
+		Message message1 = getHandler().obtainMessage();
+		Message message2 = Message.obtain();
+	}
+
+	// ---- Check recycling MotionEvent ----
+
+	public void motionEvent() {
+		MotionEvent event1 = MotionEvent.obtain(null);
+		MotionEvent event2 = MotionEvent.obtainNoHistory(null);
+	}
+
+	public void motionEvent2() {
+		MotionEvent event1 = MotionEvent.obtain(null); // OK
+		MotionEvent event2 = MotionEvent.obtainNoHistory(null); // Not recycled
+		event1.recycle();
+	}
+
+	public void motionEvent3() {
+		MotionEvent event1 = MotionEvent.obtain(null);  // Not recycled
+		MotionEvent event2 = MotionEvent.obtain(event1);
+		event2.recycle();
+	}
+
+	// ---- Using recycled objects ----
+
+	public void recycled() {
+		MotionEvent event1 = MotionEvent.obtain(null);  // Not recycled
+		event1.recycle();
+		int contents2 = event1.describeContents(); // BAD, after recycle
+		final TypedArray a = getContext().obtainStyledAttributes(new int[0]);
+		String example = a.getString(R.styleable.MyView_exampleString); // OK
+		a.recycle();
+		example = a.getString(R.styleable.MyView_exampleString); // BAD, after recycle
+	}
+
+	// ---- Check recycling Parcel ----
+
+	public void parcelOk() {
+		Parcel myparcel = Parcel.obtain();
+		myparcel.createBinderArray();
+		myparcel.recycle();
+	}
+
+	public void parcelMissing() {
+		Parcel myparcel = Parcel.obtain();
+		myparcel.createBinderArray();
+	}
+
+
+	// ---- Check suppress ----
+
+	@SuppressLint("Recycle")
+	public void recycledSuppress() {
+		MotionEvent event1 = MotionEvent.obtain(null);  // Not recycled
+		event1.recycle();
+		int contents2 = event1.describeContents(); // BAD, after recycle
+		final TypedArray a = getContext().obtainStyledAttributes(new int[0]);
+		String example = a.getString(R.styleable.MyView_exampleString); // OK
+	}
+
+	// ---- Stubs ----
+
+	static void handle(TypedArray a) {
+		// Unknown method
+	}
+
+	protected boolean something() {
+		return true;
+	}
+
+	public android.content.res.TypedArray obtainStyledAttributes(
+			AttributeSet set, int[] attrs, int defStyleAttr, int defStyleRes) {
+		return null;
+	}
+}