private volatile boolean shutdown;

    @Override
    public void shutdown() {
      shutdown = true;
    }

    @Override
    public List<Runnable> shutdownNow() {
      shutdown();
      return ImmutableList.of();
    }

    @Override
    public boolean isShutdown() {
      return shutdown;
    }

    @Override
    public boolean isTerminated() {

    private volatile boolean shutdown;

    @Override
    public void shutdown() {
      shutdown = true;
    }

    @Override
    public List<Runnable> shutdownNow() {
      shutdown();
      return ImmutableList.of();
    }

    @Override
    public boolean isShutdown() {
      return shutdown;
    }

    @Override
    public boolean isTerminated() {

    private final Object lock = new Object();

    /*
     * Conceptually, these two variables describe the executor being in
     * one of three states:
     *   - Active: shutdown == false
     *   - Shutdown: runningTasks > 0 and shutdown == true
     *   - Terminated: runningTasks == 0 and shutdown == true
     */
    @GuardedBy("lock")

  private final ListeningExecutorService delegate = newDirectExecutorService();

  @Override
  public void shutdown() {
    delegate.shutdown();
  }

  @Override
  public List<Runnable> shutdownNow() {
    return delegate.shutdownNow();
  }

  @Override
  public boolean isShutdown() {
    return delegate.isShutdown();
  }

  @Override
  public boolean isTerminated() {
    return delegate.isTerminated();
  }

  public void testStop_failed() {
    final Exception exception = new Exception("deliberate");
    TestService service =
        new TestService() {
          @Override
          protected void shutDown() throws Exception {
            super.shutDown();
            throw exception;
          }
        };
    service.startAsync().awaitRunning();
    assertEquals(1, service.startUpCalled);
    assertEquals(0, service.shutDownCalled);

 * the "running" state need to perform a periodic task. Subclasses can implement {@link #startUp},
 * {@link #shutDown} and also a {@link #runOneIteration} method that will be executed periodically.
 *
 * <p>This class uses the {@link ScheduledExecutorService} returned from {@link #executor} to run
 * the {@link #startUp} and {@link #shutDown} methods and also uses that service to schedule the

  /** Simple same thread listening executor service that doesn't handle shutdown. */
  private static class TestListeningExecutorService extends AbstractListeningExecutorService {

    @Override
    public void execute(Runnable runnable) {
      assertThat(runnable).isInstanceOf(TrustedListenableFutureTask.class);
      runnable.run();
    }

    @Override
    public void shutdown() {}

    @Override
    public List<Runnable> shutdownNow() {

      enterRun.countDown();
      try {
        exitRun.await();
      } catch (InterruptedException e) {
        throw new RuntimeException(e);
      }
    }

    @Override
    protected void shutDown() {
      assertTrue(startUpCalled);
      assertTrue(runCalled);
      assertFalse(shutDownCalled);
      shutDownCalled = true;
      assertEquals(expectedShutdownState, state());
    }

    @Override

    assertFalse(testExecutor.isTerminated());
    mock.assertLastMethodCalled("isTerminated");
    assertFalse(testExecutor.isShutdown());
    mock.assertLastMethodCalled("isShutdown");
    testExecutor.shutdown();
    mock.assertLastMethodCalled("shutdown");
    List<Runnable> list = testExecutor.shutdownNow();
    mock.assertLastMethodCalled("shutdownNow");
    assertEquals(ImmutableList.of(), list);
  }

      queue.enqueue(countDownEvent(latch));
      assertEquals(0, counters.size());
      queue.dispatch();
      latch.await();
      assertEquals(multiset(listener, 4), counters);
    } finally {
      service.shutdown();
    }
  }

  public void testEnqueueAndDispatch_multithreaded_withThrowingRunnable()
      throws InterruptedException {
    Object listener = new Object();