*/
    protected Function<Map<String, Object>, String[]> idFinder = params -> {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final SearchEngineClient client = ComponentUtil.getSearchEngineClient();
        final String index = fessConfig.getIndexDocumentUpdateIndex();
        final Object url = params.get("url");
        if (url == null) {
            return StringUtil.EMPTY_STRINGS;
        }

     *
     * @return execution result message
     */
    public String execute() {
        final SearchEngineClient searchEngineClient = ComponentUtil.getSearchEngineClient();
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final LabelTypeHelper labelTypeHelper = ComponentUtil.getLabelTypeHelper();

     *
     * @return a string containing the execution result and any error messages
     */
    public String execute() {
        final SearchEngineClient searchEngineClient = ComponentUtil.getSearchEngineClient();
        final FessConfig fessConfig = ComponentUtil.getFessConfig();

        final StringBuilder resultBuf = new StringBuilder();

        // clean up

        final String timeout = fessConfig.getCrawlerHotthreadTimeout();
        final String type = fessConfig.getCrawlerHotthreadType();
        try {
            final SearchEngineClient esClient = ComponentUtil.getSearchEngineClient();
            final NodesHotThreadsResponse response = esClient.admin()
                    .cluster()
                    .prepareNodesHotThreads()
                    .setIgnoreIdleThreads(ignoreIdleThreads)

    /**
     * Executes the ping job.
     *
     * @return the execution result
     */
    public String execute() {
        final SearchEngineClient searchEngineClient = ComponentUtil.getSearchEngineClient();
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final SystemHelper systemHelper = ComponentUtil.getSystemHelper();

        final StringBuilder resultBuf = new StringBuilder();

     * @return the number of documents processed
     */
    public static long scroll(final String index, final Function<SearchHit, Boolean> callback) {
        final SearchEngineClient client = ComponentUtil.getSearchEngineClient();
        return client.<SearchHit> scrollSearch(index, searchRequestBuilder -> true, (searchResponse, hit) -> hit,
                hit -> callback.apply(hit));
    }

    /**

        buf.append("},");
    }

    private void appendFesenStats(final StringBuilder buf) {
        String stats = null;
        try {
            final SearchEngineClient esClient = ComponentUtil.getSearchEngineClient();
            final NodesStatsResponse response = esClient.admin().cluster().prepareNodesStats().all().execute().actionGet(10000L);
            final XContentBuilder builder = XContentFactory.jsonBuilder();