/**
     * Indexes suggest data from documents.
     *
     * @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 CountDownLatch latch = new CountDownLatch(1);

            logger.info("Parsing words from indexed documents.");
            suggestHelper.indexFromDocuments(ret -> {
                logger.info("Success indexing from documents.");
                latch.countDown();
            }, t -> {
                logger.error("Failed to update suggest index.", t);

            assertTrue(success);
        };
        Consumer<Throwable> errorCallback = (error) -> {
            assertNotNull(error);
        };

        try {
            suggestHelper.indexFromDocuments(successCallback, errorCallback);
            assertTrue(true);
        } catch (Exception e) {
            assertTrue(true);
        }
    }

    @Test
    public void test_purgeDocumentSuggest() {