}

    @Test
    public void test_rejectWithNullError() throws Exception {
        final Deferred<SuggestResponse> deferred = new Deferred<>();
        final AtomicReference<Throwable> received = new AtomicReference<>();
        final CountDownLatch latch = new CountDownLatch(1);

        deferred.promise().error(error -> {
            received.set(error);
            latch.countDown();

     *
     * @param success A callback for successful indexing.
     * @param error   A callback for indexing errors.
     */
    public void indexFromDocuments(final Consumer<Boolean> success, final Consumer<Throwable> error) {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final long interval = fessConfig.getSuggestUpdateRequestIntervalAsInteger().longValue();

        new Service.Listener() {
          @Override
          public void running() {
            throw error;
          }

          @Override
          public void failed(State from, Throwable failure) {
            assertEquals(State.RUNNING, from);
            assertEquals(error, failure);
            latch.countDown();
          }
        },
        directExecutor());
    service.startAsync();

        new Service.Listener() {
          @Override
          public void running() {
            throw error;
          }

          @Override
          public void failed(State from, Throwable failure) {
            assertEquals(State.RUNNING, from);
            assertEquals(error, failure);
            latch.countDown();
          }
        },
        directExecutor());
    service.startAsync();

        try {
            if (value.getClass() == String.class) {
                return converter.getAsObject((String) value);
            }
            return converter.getAsString(value);
        } catch (final Throwable cause) {
            throw new ConverterRuntimeException(destPropertyName, value, cause);
        }
    }

    /**
     * Finds the converter corresponding to the class.
     *
     * @param clazz

            } else {
                try {
                    dataStore.store(dataConfig, indexUpdateCallback, initParamMap);
                } catch (final Throwable e) {
                    logger.error("Failed to process a data crawling: {}", dataConfig.getName(), e);
                    ComponentUtil.getComponent(FailureUrlService.class)

      new ThreadLocal<List<LockGraphNode>>() {
        @Override
        protected List<LockGraphNode> initialValue() {
          return newArrayListWithCapacity(3);
        }
      };

  /**
   * A Throwable used to record a stack trace that illustrates an example of a specific lock
   * acquisition ordering. The top of the stack trace is truncated such that it starts with the
   * acquisition of the lock in question, e.g.
   *

                        urlQueue.getUrl(), urlQueue.getDepth() != null ? urlQueue.getDepth() + 1 : 1);
            } catch (final Throwable t) {
                if (!ComponentUtil.available()) {
                    throw new ContainerNotAvailableException(t);
                }
                throw t;
            }
        }
    }

      return futureValue.set(newValue);
    }

    @CanIgnoreReturnValue
    public boolean setException(Throwable t) {
      return futureValue.setException(t);
    }

    private ListenableFuture<V> fullyFailedFuture(Throwable t) {
      return immediateFailedFuture(t);
    }

    @Override
    public void notifyNewValue(@Nullable V newValue) {

    CountDownLatch completed = new CountDownLatch(1);
    ScheduledThreadPoolExecutor delegate =
        new ScheduledThreadPoolExecutor(1) {
          @Override
          protected void afterExecute(Runnable r, Throwable t) {
            completed.countDown();
          }
        };
    ListeningScheduledExecutorService service = listeningDecorator(delegate);