logger.debug("Destroying LaContainer...");
                    }
                    destroyContainer();
                }
            };
            Runtime.getRuntime().addShutdownHook(shutdownCallback);

            systemMonitorTask = TimeoutManager.getInstance()
                    .addTimeoutTarget(new SystemMonitorTarget(), ComponentUtil.getFessConfig().getThumbnailSystemMonitorIntervalAsInteger(),

                        logger.debug("Destroying LaContainer...");
                    }
                    destroyContainer();
                }
            };
            Runtime.getRuntime().addShutdownHook(shutdownCallback);

            systemMonitorTask = TimeoutManager.getInstance()
                    .addTimeoutTarget(new SystemMonitorTarget(), ComponentUtil.getFessConfig().getSuggestSystemMonitorIntervalAsInteger(),

        .testNulls();
  }

  private static class TestApplication extends Application {
    private final List<Thread> hooks = new ArrayList<>();

    @Override
    synchronized void addShutdownHook(Thread hook) {
      hooks.add(hook);
    }

    synchronized void shutdown() throws InterruptedException {
      for (Thread hook : hooks) {
        hook.start();
      }

        .testNulls();
  }

  private static class TestApplication extends Application {
    private final List<Thread> hooks = new ArrayList<>();

    @Override
    synchronized void addShutdownHook(Thread hook) {
      hooks.add(hook);
    }

    synchronized void shutdown() throws InterruptedException {
      for (Thread hook : hooks) {
        hook.start();
      }

                @Override
                public void run() {
                    destroyContainer();
                }

            };
            Runtime.getRuntime().addShutdownHook(shutdownCallback);

            commandThread = new Thread(() -> {
                try (BufferedReader reader = new BufferedReader(new InputStreamReader(System.in))) {
                    String command;

 *           // some other action.  For now we will just exit.
 *           System.exit(1);
 *         }
 *       },
 *       MoreExecutors.directExecutor());
 *
 *     Runtime.getRuntime().addShutdownHook(new Thread() {
 *       public void run() {
 *         // Give the services 5 seconds to stop to ensure that we are responsive to shutdown
 *         // requests.
 *         try {

            return langItems;
        }
    }

    /**
     * Adds a shutdown hook.
     *
     * @param hook The shutdown hook to add.
     */
    public void addShutdownHook(final Runnable hook) {
        shutdownHookList.add(hook);
    }

    /**
     * Gets the hostname of the local machine.
     *
     * @return The hostname.
     */

        final AtomicReference<Boolean> hookExecuted = new AtomicReference<>(false);
        systemHelper.addShutdownHook(() -> hookExecuted.set(true));
        systemHelper.destroy();
        assertTrue(hookExecuted.get());
    }

    @Test
    public void test_destroy_withException() {
        systemHelper.addShutdownHook(() -> {
            throw new RuntimeException("test exception");
        });
        try {