我学我会 网上订餐系统

package com.restrant.servlet; import java.io.IOException; import java.io.PrintWriter; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import com.restrant.entity.CartItemBean; import com.restrant.entity.FoodBean; public class AddFoodToCart extends HttpServlet { /** * Constructor of the object. */ public AddFoodToCart() { super(); } /** * Destruction of the servlet. <br> */ public void destroy() { super.destroy(); // Just puts "destroy" string in log // Put your code here } /** * The doGet method of the servlet. <br> * * This method is called when a form has its tag value method equals to get. * * @param request the request send by the client to the server * @param response the response send by the server to the client * @throws ServletException if an error occurred * @throws IOException if an error occurred */ public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); request.setCharacterEncoding("GBK"); HttpSession session =request.getSession(false); String id=request.getParameter("id"); if(id!=null){ int foodid=Integer.parseInt(id); List<FoodBean> foodList = (List<FoodBean>) session .getAttribute("FoodList"); for (int i = 0; i < foodList.size(); i++) { FoodBean currentfood = (FoodBean) foodList.get(i); if (currentfood.getFoodId() == foodid) { session.setAttribute("foodToAdd", currentfood); break; }} } Map cart=(Map)session.getAttribute("cart"); FoodBean food=(FoodBean)session.getAttribute("foodToAdd"); RequestDispatcher dispatcher; if(cart==null){ cart=new HashMap(); session.setAttribute("cart", cart); } CartItemBean cartItem=(CartItemBean)cart.get(food.getFoodId()); if(cartItem!=null){ cartItem.setQuantity(cartItem.getQuantity()+1); }else{ cart.put(food.getFoodId(), new CartItemBean(food,1)); // dispatcher=request.getRequestDispatcher("/ch01/shopcart.jsp"); // dispatcher.forward(request, response); }response.sendRedirect("/restrant/ch01/shopcart.jsp"); } /** * The doPost method of the servlet. <br> * * This method is called when a form has its tag value method equals to post. * * @param request the request send by the client to the server * @param response the response send by the server to the client * @throws ServletException if an error occurred * @throws IOException if an error occurred */ public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request,response); } /** * Initialization of the servlet. <br> * * @throws ServletException if an error occurs */ public void init() throws ServletException { // Put your code here } }