*
     * - OutOfMemoryError from allocations in setFuture(): The calculus here is similar to
     * StackOverflowError: We can't reliably call setException(error).
     *
     * - Any kind of Error from a listener. Even if we could distinguish that case (by exposing some
     * extra state from AbstractFuture), our options are limited: A call to setException() would be

    RecordingListener listener = new RecordingListener();
    manager.addListener(listener, directExecutor());
    manager.startAsync().awaitHealthy();
    assertTrue(manager.isHealthy());
    assertTrue(listener.healthyCalled);
    assertFalse(listener.stoppedCalled);
    assertTrue(listener.failedServices.isEmpty());
    manager.stopAsync().awaitStopped();

    checkNotNull(unit);
    return get();
  }

  @Override
  public void addListener(Runnable runnable, Executor executor) {
    Listener listener = new Listener(runnable, executor);
    if (isDone()) {
      listener.execute();
    } else {
      listeners.add(listener);
    }
  }

  @CanIgnoreReturnValue
  protected boolean setException(Throwable throwable) {
    checkNotNull(throwable);

    CountingRemovalListener<Object, Object> listener = countingRemovalListener();
    LoadingCache<Object, Object> nullCache =
        CacheBuilder.newBuilder().maximumSize(0).removalListener(listener).build(identityLoader());
    assertEquals(0, nullCache.size());
    Object key = new Object();
    assertSame(key, nullCache.getUnchecked(key));
    assertEquals(1, listener.getCount());
    assertEquals(0, nullCache.size());

       * lets all futures share the same listener.
       *
       * We store `localFutures` inside the listener because `this.futures` might be nulled out by
       * the time the listener runs for the final future -- at which point we need to check all
       * inputs for exceptions *if* we're collecting values. If we're not, then the listener doesn't
       * need access to the futures again, so we can just pass `null`.

   *   <li>When a {@code ListenableFuture} listener is registered to run under {@code
   *       directExecutor}, the listener can execute in any of three possible threads:
   *       <ol>
   *         <li>When a thread attaches a listener to a {@code ListenableFuture} that's already
   *             complete, the listener runs immediately in that thread.
   *         <li>When a thread attaches a listener to a {@code ListenableFuture} that's

  private static final ListenerCallQueue.Event<Listener> STARTING_EVENT =
      new ListenerCallQueue.Event<Listener>() {
        @Override
        public void call(Listener listener) {
          listener.starting();
        }

        @Override
        public String toString() {
          return "starting()";
        }
      };
  private static final ListenerCallQueue.Event<Listener> RUNNING_EVENT =

  }

  @Override
  public final State state() {
    return delegate.state();
  }

  /** @since 13.0 */
  @Override
  public final void addListener(Listener listener, Executor executor) {
    delegate.addListener(listener, executor);
  }

  /** @since 14.0 */
  @Override
  public final Throwable failureCause() {
    return delegate.failureCause();
  }

  /** @since 15.0 */

          }
        };
    // Adding the listener to both futures guarantees that newFuture will always be set. Adding to
    // taskFuture guarantees completion if the callable is invoked, and adding to outputFuture
    // propagates cancellation if the callable has not yet been invoked.
    outputFuture.addListener(listener, directExecutor());
    taskFuture.addListener(listener, directExecutor());

    return outputFuture;
  }

    final Error error = new Error();
    final CountDownLatch latch = new CountDownLatch(1);
    TestService service = new TestService();
    service.addListener(
        new Service.Listener() {
          @Override
          public void running() {
            throw error;
          }

          @Override
          public void failed(State from, Throwable failure) {