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);

    /**
     * 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();