@Test
    public void test_sortBuilders() {
        queryContext = new QueryContext("test", false);
        List<SortBuilder<?>> sorts = queryContext.sortBuilders();
        assertNotNull(sorts);
        assertTrue(sorts.isEmpty());

        SortBuilder<?> sort = SortBuilders.fieldSort("field");
        queryContext.addSorts(sort);

        sorts = queryContext.sortBuilders();
        assertEquals(1, sorts.size());

        QueryContext queryContext = assertQueryBuilder(null, null, text);
        List<SortBuilder<?>> sortBuilders = queryContext.sortBuilders();
        assertEquals(1, sortBuilders.size());
        logger.info("{} => {}", text, sortBuilders.get(0).toString());
        assertEquals(expect, sortBuilders.get(0).toString().replaceAll("[\s\n]", ""));
    }

                ot = OptionalThing.empty();
            } else {
                final SortBuilder[] sortBuilders = split(sorts, ",").get(stream -> stream.filter(StringUtil::isNotBlank).map(s -> {
                    final String[] values = s.split(":");
                    if (values.length > 1) {
                        return SortBuilders.fieldSort(values[0]).order("desc".equalsIgnoreCase(values[0]) ? SortOrder.DESC : SortOrder.ASC);

        queryHelper.addDefaultSort("timestamp", "DESC");

        QueryContext context = buildQuery("test");
        assertEquals(1, context.sortBuilders().size());
        assertTrue(context.sortBuilders().get(0).toString().contains("timestamp"));
        assertTrue(context.sortBuilders().get(0).toString().contains("desc"));
    }

    @Test
    public void test_addDefaultSort_multipleFields() {

     * @return The appropriate sort builder for the field.
     */
    protected SortBuilder<?> createFieldSortBuilder(final String field, final SortOrder order) {
        if (QueryFieldConfig.SCORE_FIELD.equals(field) || QueryFieldConfig.DOC_SCORE_FIELD.equals(field)) {
            return SortBuilders.scoreSort().order(order);
        }
        return SortBuilders.fieldSort(field).order(order);
    }

    /**

                    .boostMode(CombineFunction.MULTIPLY));
            reader.addSort(SortBuilders.fieldSort(fessConfig.getIndexFieldClickCount()));
            reader.addSort(SortBuilders.scoreSort());
            return reader;
        }, docPerReq, () -> {
            systemHelper.calibrateCpuLoad();
            ThreadUtil.sleep(interval);

         */
        protected void buildSort(final QueryContext queryContext, final QueryFieldConfig queryFieldConfig, final FessConfig fessConfig) {
            queryContext.sortBuilders().forEach(sortBuilder -> searchRequestBuilder.addSort(sortBuilder));
        }

        /**
         * Builds the rescorer configuration.
         *
         * @param queryHelper the query helper