}
        final SearchHelper searchHelper = ComponentUtil.getSearchHelper();
        final FessConfig fessConfig = ComponentUtil.getFessConfig();

        if (!fessConfig.isAcceptedSearchReferer(request.getHeader("referer"))) {
            writeJsonResponse(HttpServletResponse.SC_BAD_REQUEST, escapeJsonKeyValue(MESSAGE_FIELD, "Referer is invalid."));
            return;
        }

        if (!fessConfig.isApiSearchScroll()) {