Session机制二（简易购物车案例）

一：案例一（简易购物车）

1.目录结构

2.step1.jsp

 1 <%@ page language="java" contentType="text/html; charset=utf-8"
 2     pageEncoding="utf-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
 7 <title>Insert title here</title>
 8 </head>
 9 <body>
10     <h2>Step1：选择要购买的图书</h2>
11     <form action="<%=request.getContextPath() %>/processStep1" method="post">
12         <table border="1" cellpadding="10" cellspacing="0">
13             <tr>
14                 <td>书名</td>
15                 <td>购买</td>
16             </tr>
17             <tr>
18                 <td>JAVA</td>
19                 <td><input type="checkbox" name="book" value="JAVA"></td>
20             </tr>
21             <tr>
22                 <td>Oracle</td>
23                 <td><input type="checkbox" name="book" value="Oracle"></td>
24             </tr>
25             <tr>
26                 <td>Struct2</td>
27                 <td><input type="checkbox" name="book" value="Struct2"></td>
28             </tr>
29             <tr>
30                 <td colspan="2">
31                     <input type="submit" value="Submit"/>
32                 </td>
33             </tr>
34         </table>
35     </form>
36 </body>
37 </html>

3.ProcessStep1Servlet.java

 1 package javaweb;
 2 
 3 import java.io.IOException;
 4 import javax.servlet.ServletException;
 5 import javax.servlet.annotation.WebServlet;
 6 import javax.servlet.http.HttpServlet;
 7 import javax.servlet.http.HttpServletRequest;
 8 import javax.servlet.http.HttpServletResponse;
 9 
10 /**
11  * Servlet implementation class ProcessStep1Servlet
12  */
13 @WebServlet("/processStep1")
14 public class ProcessStep1Servlet extends HttpServlet {
15     private static final long serialVersionUID = 1L;
16 
17     /**
18      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
19      */
20     protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
21         //获取选中的图书的信息
22         String[] books=request.getParameterValues("book");
23         
24         //将图书放进HttpSession中
25         request.getSession().setAttribute("books", books);
26         
27         //重定向页面到shopcart/step2.jsp
28         //这里使用的绝对路径，同理，在jsp里也需要使用相对路径
29         response.sendRedirect(request.getContextPath()+"/shopCart/step2.jsp");
30     }
31 
32 }

4.step2.jsp

 1 <%@ page language="java" contentType="text/html; charset=utf-8"
 2     pageEncoding="utf-8"%>
 3 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 4 <html>
 5 <head>
 6 <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
 7 <title>Insert title here</title>
 8 </head>
 9 <body>
10     <h2>Step2:请输入信用卡的信息</h2>
11     <form action="<%=request.getContextPath()%>/processStep2" method="post">
12         <table border="1" cellpadding="10" cellspacing="0">
13             <tr>
14                 <td colspan="2">寄送信息</td>
15             </tr>
16             <tr>
17                 <td>姓名</td>
18                 <td><input type="text" name="name" /></td>
19             </tr>
20             <tr>
21                 <td>地址</td>
22                 <td><input type="text" name="address" /></td>
23             </tr>
24             <tr>
25                 <td colspan="2">信用卡信息</td>
26             </tr>
27             <tr>
28                 <td>种类</td>
29                 <td><input type="radio" name="cardType" value="Visa" />Visa <input
30                     type="radio" name="cardType" value="Master" />Master</td>
31             </tr>
32             <tr>
33                 <td>卡号</td>
34                 <td><input type="text" name="cardNum" /></td>
35             </tr>
36             <tr>
37                 <td colspan="2"><input type="submit" value="Submit" /></td>
38             </tr>
39         </table>
40     </form>
41 </body>
42 </html><%@ page language="java" contentType="text/html; charset=utf-8"
43     pageEncoding="utf-8"%>
44 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
45 <html>
46 <head>
47 <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
48 <title>Insert title here</title>
49 </head>
50 <body>
51     <h2>Step2:请输入信用卡的信息</h2>
52     <form action="<%=request.getContextPath()%>/processStep2" method="post">
53         <table border="1" cellpadding="10" cellspacing="0">
54             <tr>
55                 <td colspan="2">寄送信息</td>
56             </tr>
57             <tr>
58                 <td>姓名</td>
59                 <td><input type="text" name="name" /></td>
60             </tr>
61             <tr>
62                 <td>地址</td>
63                 <td><input type="text" name="address" /></td>
64             </tr>
65             <tr>
66                 <td colspan="2">信用卡信息</td>
67             </tr>
68             <tr>
69                 <td>种类</td>
70                 <td><input type="radio" name="cardType" value="Visa" />Visa <input
71                     type="radio" name="cardType" value="Master" />Master</td>
72             </tr>
73             <tr>
74                 <td>卡号</td>
75                 <td><input type="text" name="cardNum" /></td>
76             </tr>
77             <tr>
78                 <td colspan="2"><input type="submit" value="Submit" /></td>
79             </tr>
80         </table>
81     </form>
82 </body>
83 </html>

5.ProcessStep2Servlet.java

 1 package javaweb;
 2 
 3 import java.io.IOException;
 4 import javax.servlet.ServletException;
 5 import javax.servlet.annotation.WebServlet;
 6 import javax.servlet.http.HttpServlet;
 7 import javax.servlet.http.HttpServletRequest;
 8 import javax.servlet.http.HttpServletResponse;
 9 
10 /**
11  * Servlet implementation class ProcessStep2Servlet
12  */
13 @WebServlet("/processStep2")
14 public class ProcessStep2Servlet extends HttpServlet {
15     private static final long serialVersionUID = 1L;
16 
17     /**
18      * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
19      */
20     protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
21         //获取请求参数name address cardType cardNum
22         String name=request.getParameter("name");
23         String address=request.getParameter("address");
24         String cardType=request.getParameter("cardType");
25         String cardNum=request.getParameter("cardNum");
26         
27         //将参入放进一个对象中
28         Customer customer=new Customer(name, address, cardType, cardNum);
29                 
30         //将请求信息存入HtppSession中        
31         request.getSession().setAttribute("customer", customer);
32         
33         //重定向到confirm.jsp
34         response.sendRedirect(request.getContextPath()+"/shopCart/confirm.jsp");
35     }
36 
37 }

6.conform.jsp

 1 <%@page import="javaweb.Customer"%>
 2 <%@ page language="java" contentType="text/html; charset=utf-8"
 3     pageEncoding="utf-8"%>
 4 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
 5 <html>
 6 <head>
 7 <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
 8 <title>Insert title here</title>
 9 </head>
10 <body>
11     <%
12         Customer customer=(Customer)session.getAttribute("customer");
13         String[] books=(String[])session.getAttribute("books");
14     %>
15     <h2>Step3:请确认</h2>
16     <table>
17         <tr>
18             <td>顾客姓名</td>
19             <td><%=customer.getName() %></td>
20         </tr>
21         <tr>
22             <td>顾客地址</td>
23             <td><%=customer.getAddress() %></td>
24         </tr>
25         <tr>
26             <td>顾客卡号</td>
27             <td><%=customer.getCardNum() %></td>
28         </tr>
29         <tr>
30             <td>顾客类型</td>
31             <td><%=customer.getCardType() %></td>
32         </tr>
33         <tr>
34             <td>Books</td>
35             <td>
36                 <%
37                     for(String book:books){
38                         out.print(book);
39                         out.print("<br>");
40                     }
41                 %>
42             </td>        
43         </tr>
44     </table>
45 </body>
46 </html>

7.补充简单bean，Customer.java

 1 package javaweb;
 2 
 3 public class Customer {
 4     private String name;
 5     private String address;
 6     private String cardType;
 7     private String cardNum;
 8     public Customer() {
 9         
10     }
11     public Customer(String name, String address, String cardType, String cardNum) {
12         super();
13         this.name = name;
14         this.address = address;
15         this.cardType = cardType;
16         this.cardNum = cardNum;
17     }
18     public String getName() {
19         return name;
20     }
21     public void setName(String name) {
22         this.name = name;
23     }
24     public String getAddress() {
25         return address;
26     }
27     public void setAddress(String address) {
28         this.address = address;
29     }
30     public String getCardType() {
31         return cardType;
32     }
33     public void setCardType(String cardType) {
34         this.cardType = cardType;
35     }
36     public String getCardNum() {
37         return cardNum;
38     }
39     public void setCardNum(String cardNum) {
40         this.cardNum = cardNum;
41     }
42     
43 }

8.展示结果

二：