Adding a router class to handle messages that expect responses.

mojo/android/javatests/src/org/chromium/mojo/bindings/AutoCloseableRouterTest.java

Index: mojo/android/javatests/src/org/chromium/mojo/bindings/AutoCloseableRouterTest.java
diff --git a/mojo/android/javatests/src/org/chromium/mojo/bindings/AutoCloseableRouterTest.java b/mojo/android/javatests/src/org/chromium/mojo/bindings/AutoCloseableRouterTest.java
new file mode 100644
index 0000000000000000000000000000000000000000..ee83de3005d98dbcbfdca82119e97f85269f1e6b
--- /dev/null
+++ b/mojo/android/javatests/src/org/chromium/mojo/bindings/AutoCloseableRouterTest.java
@@ -0,0 +1,96 @@
+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.mojo.bindings;
+
+import android.test.suitebuilder.annotation.SmallTest;
+
+import org.chromium.mojo.MojoTestCase;
+import org.chromium.mojo.system.Core;
+import org.chromium.mojo.system.MessagePipeHandle;
+import org.chromium.mojo.system.impl.CoreImpl;
+
+import java.lang.ref.WeakReference;
+
+/**
+ * Testing the the AutoCloseableRouter.
+ */
+public class AutoCloseableRouterTest extends MojoTestCase {
+
+    private static final long RUN_LOOP_TIMEOUT_MS = 25;
+
+    private static class CloseRecordingRouter implements Router {
+
+        private Thread mThread = null;
+
+        @Override
+        public boolean acceptWithResponder(MessageWithHeader message, MessageReceiver responder) {
+            return false;
+        }
+
+        @Override
+        public boolean accept(MessageWithHeader message) {
+            return false;
+        }
+
+        @Override
+        public MessagePipeHandle passHandle() {
+            return null;
+        }
+
+        @Override
+        public void start() {
+        }
+
+        @Override
+        public void setIncomingMessageReceiver(
+                MessageReceiverWithResponder incomingMessageReceiver) {
+        }
+
+        @Override
+        public void setErrorHandler(ConnectionErrorHandler errorHandler) {
+        }
+
+        /**
+         * Record the thread it was last called on.
+         */
+        @Override
+        public void close() {
+            mThread = Thread.currentThread();
+        }
+
+        /**
+         * Returns the thread this router was last called on. Returns |null| if it was never closed.
+         */
+        public Thread getClosingThread() {
+            return mThread;
+        }
+    }
+
+    /**
+     * Testing that an {@link AutoCloseableRouter} close its delegate when getting deallocated.

[rmcilroy, 2014/07/14 14:44:57]

Test that an {@link AutoCloseableRouter} closes its delegate when it is
deallocated.

[qsr, 2014/07/15 12:03:16]

Done.

+     */
+    @SmallTest
+    public void testCloseOnDeallocation() {
+        Core core = CoreImpl.getInstance();
+        CloseRecordingRouter closeRecordingRouter = new CloseRecordingRouter();
+        AutoCloseableRouter autoCloseableRouter = new AutoCloseableRouter(core,
+                closeRecordingRouter);
+        WeakReference<AutoCloseableRouter> weakRef = new WeakReference<AutoCloseableRouter>(
+                autoCloseableRouter);
+
+        assertNotNull(weakRef.get());
+        assertNull(closeRecordingRouter.getClosingThread());
+
+        autoCloseableRouter = null;
+        System.gc();
+        System.runFinalization();

[rmcilroy, 2014/07/14 14:44:57]

Hmm, both System.gc and System.runFinalization are only suggestions to the VM
(and I don't think System.gc will do anything synchronously on newer versions of
Android) so this test will probably be very flaky.  I can't think of any
solution though.

[qsr, 2014/07/15 12:03:15]

 Would you prefer I just remove the test? As you said, I do not have a lot of
leeway here...

[rmcilroy, 2014/07/15 18:11:57]

Yes

[qsr, 2014/07/16 08:53:31]

Done.

+
+        assertNull(weakRef.get());
+
+        nativeRunLoop(RUN_LOOP_TIMEOUT_MS);
+
+        assertEquals(Thread.currentThread(), closeRecordingRouter.getClosingThread());
+    }
+}