Ajax

开发平台：
Java

AddItem.java：源码内容
							/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package servlet;
import Entity.Item;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
 *
 * @author rincewind
 */
public class AddItem extends HttpServlet {
   
    
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        ArrayList<Item> items=new ArrayList();
        String name=request.getParameter("itemid");     //接受商品名称
        String num=request.getParameter("num");          //接受商品数               //将其转化为整型
        String price=request.getParameter("price");
        HttpSession session=request.getSession();
        String[] info=new String[4];
        Item item=new Item();                       //用类封装
          item.setItemname(name);
          item.setPrice("1");
          item.setNum(num);
        try {
         if(session.getAttribute("items")==null){     //第一次购物
               items.add(item);                      //将商品添加到已经购物的商品中
               session.setAttribute("items",items);
         }else{                                       //以后添加商品
             items=(ArrayList<Item>) session.getAttribute("items");
             items.add(item);
             session.setAttribute("items",items);
         }
         int num1=Integer.parseInt(num);
         int p1=Integer.parseInt(price);
         int sum=num1*p1;
           String result="{name:'"+name+"',price:'"+price+"',num:'"+num+"',sum:'"+String.valueOf(sum)+"'}";
           out.print(result);
        }catch(Exception e){
            request.setAttribute("error", e.getMessage());
           out.print(e.getMessage());
        } finally { 
            out.close();
        }
    } 
    // <editor-fold defaultstate="collapsed" desc="HttpServlet 方法。单击左侧的 + 号以编辑代码。">
    /** 
     * Handles the HTTP <code>GET</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    } 
    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }
    /** 
     * Returns a short description of the servlet.
     * @return a String containing servlet description
     */
    @Override
    public String getServletInfo() {
        return "Short description";
    }// </editor-fold>
}

						