@Override
	protected void service(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		log.debug("JServer - " + TAG + " is invoked");
		log.debug(TAG + " receiveed : " + request.getContentLength() + " bytes");
		String uid = request.getParameter("uid");
		if(uid == null) {
			log.error("Error : uid is required");
			responseError(response, "Error : uid is required");
			return;
		}
		User user = qs.getUser(uid);
		if(user == null) {
			log.error("get user error, user == null!");
			return;
		}
		log.debug("get user ok ! username : " + user.username );
		Gson gson = new Gson();
		Map<String, String> params = new HashMap<String, String>();
		params.put("username", user.username);
		String info = gson.toJson(params);
		response.getOutputStream().write(info.getBytes());
	}