}
  }

  /**
   * Invoke this method to transition the service to the {@link State#FAILED}. The service will
   * <b>not be stopped</b> if it is running. Invoke this method when a service has failed critically
   * or otherwise cannot be started nor stopped.
   */
  protected final void notifyFailed(Throwable cause) {
    checkNotNull(cause);

    monitor.enter();
    try {

  public final void awaitTerminated() {
    monitor.enterWhenUninterruptibly(isStopped);
    try {
      checkCurrentState(TERMINATED);
    } finally {
      monitor.leave();
    }
  }

  @Override
  public final void awaitTerminated(long timeout, TimeUnit unit) throws TimeoutException {
    if (monitor.enterWhenUninterruptibly(isStopped, timeout, unit)) {
      try {
        checkCurrentState(TERMINATED);

      new ListenerCallQueue.Event<Listener>() {
        @Override
        public void call(Listener listener) {
          listener.stopped();
        }

        @Override
        public String toString() {
          return "stopped()";
        }
      };

  /**
   * A listener for the aggregate state changes of the services that are under management. Users

   * this initiates service shutdown and returns immediately. If the service is {@linkplain
   * State#NEW new}, it is {@linkplain State#TERMINATED terminated} without having been started nor
   * stopped. If the service has already been stopped, this method returns immediately without
   * taking action.
   *
   * @return this
   * @since 15.0
   */
  @CanIgnoreReturnValue
  Service stopAsync();

  /**

   * this initiates service shutdown and returns immediately. If the service is {@linkplain
   * State#NEW new}, it is {@linkplain State#TERMINATED terminated} without having been started nor
   * stopped. If the service has already been stopped, this method returns immediately without
   * taking action.
   *
   * @return this
   * @since 15.0
   */
  @CanIgnoreReturnValue
  Service stopAsync();

  /**

    manager.awaitStopped(5, SECONDS); // no exception thrown
  }

  /**
   * This covers a case where if the last service to stop failed then the stopped callback would
   * never be called.
   */
  public void testSingleFailedServiceCallsStopped() {
    Service a = new FailStartService();
    ServiceManager manager = new ServiceManager(asList(a));

        } catch (final ContainerNotAvailableException e) {
            if (logger.isDebugEnabled()) {
                logger.debug("SuggestCreator is stopped.", e);
            } else if (logger.isInfoEnabled()) {
                logger.info("SuggestCreator is stopped.");
            }
            exitCode = Constants.EXIT_FAIL;
        } catch (final Throwable t) {

        } catch (final ContainerNotAvailableException e) {
            if (logger.isDebugEnabled()) {
                logger.debug("Crawler is stopped.", e);
            } else if (logger.isInfoEnabled()) {
                logger.info("Crawler is stopped.");
            }
            exitCode = Constants.EXIT_FAIL;
        } catch (final Throwable t) {
            logger.error("Crawler does not work correctly.", t);

        }

        try {
            dataIndexHelper.crawl("test-session-force-stop");
            assertTrue("Should exit quickly when force stopped", true);
        } catch (Exception e) {
            assertTrue("Force stop should handle exceptions quickly", true);
        }
    }

    public void test_crawl_with_short_intervals() {
        try {

                } finally {
                    if (systemHelper.isForceStop()) {
                        finishCrawling = true;
                        if (logger.isDebugEnabled()) {
                            logger.debug("Stopped indexUpdater.");
                        }
                    }
                }

                if (emptyListCount >= maxEmptyListCount) {
                    if (logger.isInfoEnabled()) {