ajax response from portlet controller class overriding serveResource method
JSONObject jsonObject = JSONFactoryUtil.createJSONObject();
jsonObject.put("success", success);
jsonObject.put("message", "validated");
HttpServletResponse servletResponse = PortalUtil
.getHttpServletResponse(resourceResponse);
PrintWriter pw;
try {
pw = servletResponse.getWriter();
pw.write(jsonObject.toString());
pw.close();
} catch (IOException e) {
}