if (responseFields != null) {
                searchRequestBuilder.setFetchSource(responseFields, null);
            }

            // rescorer
            buildRescorer(queryHelper, queryFieldConfig, fessConfig);

            // sort
            buildSort(queryContext, queryFieldConfig, fessConfig);

            // highlighting
            if (highlightInfo != null) {

        final SearchRequestBuilder builder = client.prepareSearch(index);
        builder.setSize(size);
        builder.setQuery(buildQuery());
        builder.setRescorer(buildRescore(), windowSize);

        builder.execute(new ActionListener<SearchResponse>() {
            @Override
            public void onResponse(final SearchResponse searchResponse) {

    }

    @Test
    public void test_buildRescore() throws Exception {
        PopularWordsRequest request = new PopularWordsRequest();
        request.setSeed("test-seed");

        assertNotNull(request.buildRescore());
    }

    @Test
    public void test_constructor() throws Exception {
        PopularWordsRequest request = new PopularWordsRequest();
        assertNotNull(request);
    }