final SearchEngineClient searchEngineClient = ComponentUtil.getSearchEngineClient();
                final String index = fessConfig.getIndexDocumentUpdateIndex();
                searchEngineClient.admin().indices().prepareRefresh(index).execute().actionGet();
                final long numOfDeleted = searchEngineClient.deleteByQuery(index, queryBuilder);
                logger.info("Deleted {} old docs.", numOfDeleted);

     * @return the refresh status code
     */
    protected int refreshIndex(final SearchEngineClient searchEngineClient, final String index) {
        final RefreshResponse response = searchEngineClient.admin().indices().prepareRefresh(index).execute().actionGet();
        if (logger.isDebugEnabled()) {
            logger.debug("[{}] refresh status: {} ({}/{}/{})", index, response.getStatus(), response.getTotalShards(),

     *
     * @param indices the indices to refresh
     */
    public void refresh(final String... indices) {
        client.admin().indices().prepareRefresh(indices).execute(new ActionListener<RefreshResponse>() {
            @Override
            public void onResponse(final RefreshResponse response) {
                if (logger.isDebugEnabled()) {