}

  public void testListenInPoolThreadUsesGivenExecutor() throws Exception {
    ExecutorService executorService =
        newCachedThreadPool(new ThreadFactoryBuilder().setDaemon(true).build());
    NonListenableSettableFuture<String> abstractFuture = NonListenableSettableFuture.create();
    ExecutorSpy spy = new ExecutorSpy(executorService);
    ListenableFuture<String> listenableFuture = listenInPoolThread(abstractFuture, spy);

     * test the forwarded methods
     */
  }

  @AndroidIncompatible // Mocking ExecutorService is forbidden there. TODO(b/218700094): Don't mock.
  public void testListeningDecorator_noWrapExecuteTask() {
    ExecutorService delegate = mock(ExecutorService.class);
    ListeningExecutorService service = listeningDecorator(delegate);
    Runnable task = () -> {};
    service.execute(task);

     * test the forwarded methods
     */
  }

  @AndroidIncompatible // Mocking ExecutorService is forbidden there. TODO(b/218700094): Don't mock.
  public void testListeningDecorator_noWrapExecuteTask() {
    ExecutorService delegate = mock(ExecutorService.class);
    ListeningExecutorService service = listeningDecorator(delegate);
    Runnable task = () -> {};
    service.execute(task);

    ExecutorService delegate =
        new ThreadPoolExecutor(0, Integer.MAX_VALUE, 60, SECONDS, new SynchronousQueue<>()) {
          @Override
          public void close() {
            throw new AssertionError(
                "ForwardingExecutorService should have used the default method"
                    + " ExecutorService.close() (which would forward to methods like shutdown() on"

  }

  public void testListenInPoolThreadUsesGivenExecutor() throws Exception {
    ExecutorService executorService =
        newCachedThreadPool(new ThreadFactoryBuilder().setDaemon(true).build());
    NonListenableSettableFuture<String> abstractFuture = NonListenableSettableFuture.create();
    ExecutorSpy spy = new ExecutorSpy(executorService);
    ListenableFuture<String> listenableFuture = listenInPoolThread(abstractFuture, spy);

    ExecutorService delegate =
        new ThreadPoolExecutor(0, Integer.MAX_VALUE, 60, SECONDS, new SynchronousQueue<>()) {
          @Override
          public void close() {
            throw new AssertionError(
                "ForwardingExecutorService should have used the default method"
                    + " ExecutorService.close() (which would forward to methods like shutdown() on"

            ThumbnailManager mockThumbnailManager = new ThumbnailManager() {
                private int callCount = 0;

                @Override
                public int generate(ExecutorService executorService, boolean cleanup) {
                    // Return 0 to exit the loop
                    if (callCount++ == 0) {
                        return 1;
                    }
                    return 0;

        int count = 1;
        final ExecutorService executorService = Executors.newFixedThreadPool(options.numOfThreads);
        try {
            while (count != 0) {
                count = ComponentUtil.getThumbnailManager().generate(executorService, options.cleanup);
                totalCount += count;
            }
            executorService.shutdown();
            executorService.awaitTermination(60, TimeUnit.SECONDS);

  @GwtIncompatible // concurrency
  private void runConcurrentTest(int numberOfThreads, Callable<@Nullable Void> callable)
      throws Exception {
    ExecutorService executorService = newFixedThreadPool(numberOfThreads);
    try {
      CountDownLatch startLatch = new CountDownLatch(numberOfThreads);
      CountDownLatch doneLatch = new CountDownLatch(numberOfThreads);

  @GwtIncompatible // concurrency
  private void runConcurrentTest(int numberOfThreads, Callable<@Nullable Void> callable)
      throws Exception {
    ExecutorService executorService = newFixedThreadPool(numberOfThreads);
    try {
      CountDownLatch startLatch = new CountDownLatch(numberOfThreads);
      CountDownLatch doneLatch = new CountDownLatch(numberOfThreads);