会话管理 session实现多页面传输数据-白红宇

以下面购物车几个页面传输数据为例html页面有index.html

1  2  3  4     
      5     首页 6      7  8  9 
     
      10     
      服装
11     
      食品
12     
      电子
13 
     
14 15 22 23

后面是三个副页fuzhuang.html;shipin.html;dianzi.html

fuzhuang.html

1  2  3  4     
      5     服装 6      7  8  9 
     
      10     
      服装111     
      服装212     
      服装313     
      服装414     
      15     
      16 
     
17 回到首页18 26 27

dianzi.html

1  2  3  4     
      5     电子 6      7  8  9 
     
      10     
      电子111     
      电子212     
      电子313     
      电子414     
      15     
      16 
     
17 回到首页18 26 27

shipin.html

Servlet中两个页面 Addlist.java

1 package control; 2  3 import javax.servlet.ServletException; 4 import javax.servlet.annotation.WebServlet; 5 import javax.servlet.http.HttpServlet; 6 import javax.servlet.http.HttpServletRequest; 7 import javax.servlet.http.HttpServletResponse; 8 import javax.servlet.http.HttpSession; 9 import java.io.IOException;10 import java.io.PrintWriter;11 import java.util.ArrayList;12 import java.util.List;13 14 @WebServlet("/addList")15 public class AddList extends HttpServlet {16     protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {17         request.setCharacterEncoding("utf-8");18         String[] goods=request.getParameterValues("fz");19         String[] goods1=request.getParameterValues("dz");20         String[] goods2=request.getParameterValues("sp");21         HttpSession session=request.getSession();22         List
     
       listgoods=(List
      
       ) session.getAttribute("goods");23         if (listgoods==null){24             listgoods=new ArrayList<>();25             session.setAttribute("goods",listgoods);26         }27         if(goods!=null){
   for (String s:goods){28             System.out.println(s+"   ");29             listgoods.add(s);30         }}31         if(goods1!=null){
   for (String s:goods1){32             System.out.println(s+"   ");33             listgoods.add(s);34         }}35         if(goods2!=null){
   for (String s:goods2){36             System.out.println(s+"   ");37             listgoods.add(s);38         }}39         response.setCharacterEncoding("utf-8");40         response.setContentType("application/json;charset=utf-8");41         PrintWriter out=response.getWriter();42         out.write("{\"status\":\"添加成功\"}");43         out.close();44 45     }46 47     protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {48 49     }50 }

Getgoods.java

1 package control; 2  3 import javax.servlet.ServletException; 4 import javax.servlet.annotation.WebServlet; 5 import javax.servlet.http.HttpServlet; 6 import javax.servlet.http.HttpServletRequest; 7 import javax.servlet.http.HttpServletResponse; 8 import javax.servlet.http.HttpSession; 9 import java.io.IOException;10 import java.io.PrintWriter;11 import java.util.List;12 13 @WebServlet("/getgoods")14 public class Getgoods extends HttpServlet {15     @Override16     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {17         HttpSession session=req.getSession();18         List
     
       goods=(List
      
       ) session.getAttribute("goods");19         resp.setContentType("application/json;charset=utf-8");20         PrintWriter out=resp.getWriter();21         if (goods==null){22             out.write("{\"goods\":"+null+"}");23         }else{24             Object[] arr=goods.toArray();25             String s="{\"goods\":[";26             for (int i=0;i