public void updateDishInfo() {
		int dish_id;
		String dish_name, user_id, user_password;
		double dish_price;
		try {
			dish_id = Integer.valueOf(request.getParameter("dish_id").trim());
			dish_name = request.getParameter("dish_name").trim();
			user_id = request.getParameter("user_id").trim();
			user_password = request.getParameter("user_password").trim();
			dish_price = Double.valueOf(request.getParameter("dish_price").trim());
		} catch (Exception e) {
			jsonObject.put("RC", RC.PARAMETER_ERROR);
			return;
		}

		UserInfo userInfo;
		try {
			userInfo = new UserInfoDao().getById(user_id);
		} catch (Exception e) {
			jsonObject.put("RC", RC.SQL_EXCEPTION);
			return;
		}
		if (userInfo == null) {
			jsonObject.put("OC", OC.UNKNOWN_USER_ID);
			return;
		} else if (userInfo.getUser_password().equals(user_password)) {
			jsonObject.put("OC", OC.WRONG_PASSWORD);
			return;
		} else if (userInfo.getUser_type().equals("customer")) {
			jsonObject.put("OC", OC.INSUFFICIENT_PRIVILEGES);
			return;
		}

		DishInfoDao dishInfoDao;
		try {
			dishInfoDao = new DishInfoDao();
		} catch (Exception e) {
			jsonObject.put("RC", RC.SQL_EXCEPTION);
			return;
		}
		DishInfo dishInfo = dishInfoDao.getById(dish_id);
		if (dishInfo == null) {
			jsonObject.put("OC", OC.UNKNOWN_DISH_ID);
			return;
		}
		dishInfo.setDish_name(dish_name);
		dishInfo.setDish_price(dish_price);
		jsonObject.put("OC", dishInfoDao.Update(dishInfo));
	}