// thread because the task will block on the task latch after unblocking
    // the run latch.
    exec.execute(task);
    runLatch.await();
    assertEquals(1, listenerLatch.getCount());
    assertFalse(task.isDone());
    assertFalse(task.isCancelled());

    // Finish the task by unblocking the task latch.  Then wait for the
    // listener to be called by blocking on the listener latch.
    taskLatch.countDown();

    return new CheckedCallable<String>() {
      @Override
      protected String realCall() {
        try {
          latch.await();
        } catch (InterruptedException quittingTime) {
        }
        return TEST_STRING;
      }
    };
  }

  public Runnable awaiter(final CountDownLatch latch) {
    return new CheckedRunnable() {

  }

  private static class NoOpThreadedService extends AbstractExecutionThreadService {
    final CountDownLatch latch = new CountDownLatch(1);

    @Override
    protected void run() throws Exception {
      latch.await();
    }

    @Override
    protected void triggerShutdown() {
      latch.countDown();
    }
  }

  private static class StartFailingService extends AbstractService {
    @Override

   * <p>Fingerprint2011() is a form of Murmur2 on strings up to 32 bytes and a form of CityHash for
   * longer strings. It could have been one or the other throughout. The main advantage of the
   * combination is that CityHash has a bunch of special cases for short strings that don't need to
   * be replicated here. The result will never be 0 or 1.
   *
   * <p>This function is best understood as a <a

 *
 * <p>Here's an example that tests a {@code finalize} method:
 *
 * <pre>{@code
 * final CountDownLatch latch = new CountDownLatch(1);
 * Object x = new MyClass() {
 *   ...
 *   protected void finalize() { latch.countDown(); ... }
 * };
 * x = null;  // Hint to the JIT that x is stack-unreachable
 * GcFinalization.await(latch);
 * }</pre>
 *
 * <p>Here's an example that uses a user-defined finalization predicate:
 *

    final CountDownLatch latch = new CountDownLatch(1);
    final SettableFuture<?> future = SettableFuture.create();
    final Executor delegate =
        new Executor() {
          @Override
          public void execute(Runnable task) {
            if (future.set(null)) {
              awaitUninterruptibly(latch);
            }
            throw new RejectedExecutionException();

  public Callable<String> latchAwaitingStringTask(final CountDownLatch latch) {
    return new CheckedCallable<String>() {
      protected String realCall() {
        try {
          latch.await();
        } catch (InterruptedException quittingTime) {
        }
        return TEST_STRING;
      }
    };
  }

  public Runnable awaiter(final CountDownLatch latch) {
    return new CheckedRunnable() {

  }

  private static class NoOpThreadedService extends AbstractExecutionThreadService {
    final CountDownLatch latch = new CountDownLatch(1);

    @Override
    protected void run() throws Exception {
      latch.await();
    }

    @Override
    protected void triggerShutdown() {
      latch.countDown();
    }
  }

  private static class StartFailingService extends AbstractService {
    @Override

    assertWithMessage("Nothing should be logged")
        .that(aggregateFutureLogHandler.getStoredLogRecords())
        .isEmpty();

    // Not even if there are a bunch of failures.
    assertEquals(
        newArrayList(null, null, null),
        getDone(
            successfulAsList(
                immediateFailedFuture(new MyException()),

public abstract class AbstractListenableFutureTest extends TestCase {

  protected CountDownLatch latch;
  protected ListenableFuture<Boolean> future;

  @Override
  protected void setUp() throws Exception {

    // Create a latch and a future that waits on the latch.
    latch = new CountDownLatch(1);
    future = createListenableFuture(Boolean.TRUE, null, latch);
  }

  @Override
  protected void tearDown() throws Exception {