boolean generate(String thumbnailId, File outputFile);

    boolean isTarget(Map<String, Object> docMap);

    boolean isAvailable();

    void destroy();

    Tuple3<String, String, String> createTask(String path, Map<String, Object> docMap);

    private static final Logger logger = LogManager.getLogger(HtmlTagBasedGenerator.class);

    @Override
    public void destroy() {
    }

    @Override
    public Tuple3<String, String, String> createTask(final String path, final Map<String, Object> docMap) {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final String thumbnailId = DocumentUtil.getValue(docMap, fessConfig.getIndexFieldId(), String.class);

                return found;
            });
        } else {
            available = true;
        }
        return available;
    }

    @Override
    public Tuple3<String, String, String> createTask(final String path, final Map<String, Object> docMap) {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final String thumbnailId = DocumentUtil.getValue(docMap, fessConfig.getIndexFieldId(), String.class);

            if (generator.isTarget(docMap)) {
                final String path = getImageFilename(docMap);
                final Tuple3<String, String, String> task = generator.createTask(path, docMap);
                if (task != null) {
                    if (logger.isDebugEnabled()) {
                        logger.debug("Add thumbnail task: {}", task);
                    }

      mock.assertLastMethodCalled("submit");
      assertEquals(RESULT_VALUE, f.get());
    }
  }

  public void testInvokeAll() throws InterruptedException, ExecutionException {
    List<Callable<String>> tasks = createTasks(3);
    {
      MockExecutor mock = new MockExecutor();
      TestExecutor testExecutor = new TestExecutor(mock);
      List<Future<String>> futures = testExecutor.invokeAll(tasks);

      mock.assertLastMethodCalled("submit");
      assertEquals(RESULT_VALUE, f.get());
    }
  }

  public void testInvokeAll() throws InterruptedException, ExecutionException {
    List<Callable<String>> tasks = createTasks(3);
    {
      MockExecutor mock = new MockExecutor();
      TestExecutor testExecutor = new TestExecutor(mock);
      List<Future<String>> futures = testExecutor.invokeAll(tasks);