public void updateValueOnly() {
		UserLabel userLabel = new UserLabel();
		String user_password;
		try {
			userLabel.setUser_id(request.getParameter("user_id").trim());
			user_password = request.getParameter("user_password").trim();
		} catch (Exception e) {
			jsonObject.put("RC", RC.PARAMETER_ERROR);
			return;
		}

		UserInfo userInfo;
		try {
			userInfo = new UserInfoDao().getById(userLabel.getUser_id());
		} catch (Exception e) {
			jsonObject.put("RC", RC.SQL_EXCEPTION);
			return;
		}
		if (userInfo == null) {
			jsonObject.put("OC", OC.UNKNOWN_USER_ID);
			return;
		}
		if (!userInfo.getUser_password().equals(user_password)) {
			jsonObject.put("OC", OC.WRONG_PASSWORD);
			return;
		}
		//set stable user label.
		userLabel.setUser_label1("酸");
		userLabel.setUser_label2("甜");
		userLabel.setUser_label3("苦");
		userLabel.setUser_label4("辣");
		userLabel.setUser_label5("咸");
		userLabel.setUser_label_value1(request.getParameter("user_label_value1"));
		userLabel.setUser_label_value2(request.getParameter("user_label_value2"));
		userLabel.setUser_label_value3(request.getParameter("user_label_value3"));
		userLabel.setUser_label_value4(request.getParameter("user_label_value4"));
		userLabel.setUser_label_value5(request.getParameter("user_label_value5"));

		try {
			jsonObject.put("OC", new UserLabelDao().update(userLabel));
		} catch (Exception e) {
			jsonObject.put("RC", RC.SQL_EXCEPTION);
			return;
		}
	}