会话管理 session实现多页面传输数据

以下面购物车几个页面传输数据为例html页面有index.html

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>首页</title>
 6     <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
 7 </head>
 8 <body>
 9 <ul>
10     <li><a href="fuzhuang.html">服装</a></li>
11     <li><a href="shipin.html">食品</a></li>
12     <li><a href="dianzi.html">电子</a></li>
13 </ul>
14 <input type="button" id="view" value="查看购物车">
15 <script>
16     $("#view").click(function () {
17         $.get("getgoods",function (data) {
18             alert(data.goods);
19         });
20     });
21 </script>
22 </body>
23 </html>

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

fuzhuang.html

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>服装</title>
 6     <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
 7 </head>
 8 <body>
 9 <form id="fuz">
10     <input type="checkbox" name="fz" value="服装1"/>服装1
11     <input type="checkbox" name="fz" value="服装2"/>服装2
12     <input type="checkbox" name="fz" value="服装3"/>服装3
13     <input type="checkbox" name="fz" value="服装4"/>服装4
14     <input type="button" value="添加" id="add-btn"/>
15     <input type="button" value="查看购物车"/>
16 </form>
17 <a href="index.html">回到首页</a>
18 <script>
19     $("#add-btn").click(function () {
20         var d=$("#fuz").serialize();
21         $.post("addList",d,function (data) {
22          alert(data.status);
23         });
24     });
25 </script>
26 </body>
27 </html>

dianzi.html

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>电子</title>
 6     <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
 7 </head>
 8 <body>
 9 <form id="dzs">
10     <input type="checkbox" name="dz" value="电子1">电子1
11     <input type="checkbox" name="dz" value="电子2">电子2
12     <input type="checkbox" name="dz" value="电子3">电子3
13     <input type="checkbox" name="dz" value="电子4">电子4
14     <input type="button" value="添加" id="add-btn">
15     <input type="button" value="查看购物车">
16 </form>
17 <a href="index.html">回到首页</a>
18 <script>
19     $("#add-btn").click(function () {
20         var d=$("#dzs").serialize();
21         $.post("addList",d,function (data) {
22             alert(data.status);
23         });
24     });
25 </script>
26 </body>
27 </html>

shipin.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>食品</title>
    <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
</head>
<body>
<form id="sps">
    <input type="checkbox" name="sp" value="食品1">食品1
    <input type="checkbox" name="sp" value="食品2">食品2
    <input type="checkbox" name="sp" value="食品3">食品3
    <input type="checkbox" name="sp" value="食品4">食品4
    <input type="button" value="添加" id="add-btn">
    <input type="button" value="查看购物车">
</form>
<a href="index.html">回到首页</a>
<script>
    $("#add-btn").click(function () {
        var d=$("#sps").serialize();
        $.ajax({url:"addList",
            type:"post",
            data:d,
            success:function (data) {
             alert(data.status)
        }});
    });
</script>
</body>
</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<String> listgoods=(List<String>) 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     @Override
16     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
17         HttpSession session=req.getSession();
18         List<String> goods=(List<String>) 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<arr.length;i++){
27                 s+="""+arr[i]+""";
28                 if (i<arr.length-1)
29                     s+=",";
30             }
31             s+="]}";
32             System.out.println(s);
33             out.write(s);
34     }
35     out.close();
36     }
37 }