// facet field
                buf.append(',');
                buf.append("\"facet_field\":[");
                if (facetResponse.getFieldList() != null) {
                    boolean first1 = true;
                    for (final Field field : facetResponse.getFieldList()) {
                        if (!first1) {
                            buf.append(',');
                        } else {

            if (facetResponse != null && facetResponse.hasFacetResponse()) {
                // facet field
                if (facetResponse.getFieldList() != null) {
                    facetField = facetResponse.getFieldList().stream().map(field -> {
                        final Map<String, Object> fieldMap = new HashMap<>(2, 1f);
                        fieldMap.put("name", field.getName());