return new HighlightInfo();
        }
    }

    @Override
    protected void writeHeaders(final HttpServletResponse response) {
        ComponentUtil.getFessConfig().getApiJsonResponseHeaderList().forEach(e -> response.setHeader(e.getFirst(), e.getSecond()));
    }

    protected void writeJsonResponse(final int status, final Throwable t) {
        final Supplier<String> stacktraceString = () -> {

            propMap.put(API_GSA_RESPONSE_HEADER_LIST, list);
        }
        return list;
    }

    String getApiJsonResponseHeaders();

    default List<Pair<String, String>> getApiJsonResponseHeaderList() {
        @SuppressWarnings("unchecked")
        List<Pair<String, String>> list = (List<Pair<String, String>>) propMap.get(API_JSON_RESPONSE_HEADER_LIST);
        if (list == null) {