final Object url = params.get("url");
        if (url == null) {
            return StringUtil.EMPTY_STRINGS;
        }
        final SearchResponse response = client.prepareSearch(index)
                .setQuery(QueryBuilders.termQuery(fessConfig.getIndexFieldUrl(), url))
                .setFetchSource(false)
                .setSize(fessConfig.getPageScoreBoosterMaxFetchSizeAsInteger())

    }

    @Override
    protected void processRequest(final Client client, final Deferred<PopularWordsResponse> deferred) {
        final SearchRequestBuilder builder = client.prepareSearch(index);
        builder.setSize(size);
        builder.setQuery(buildQuery());
        builder.setRescorer(buildRescore(), windowSize);

        builder.execute(new ActionListener<SearchResponse>() {