总结学了 j2ee 一月半后的项目情况(2)

源码: 韩顺平 j2ee myshopping（MODEL2）

1、数据库链接和数据库CRUD类

 1 package fafa.shop.util;
 2 
 3 import java.sql.*;
 4 
 5 public class DBUtil {
 6     private static final String DBDRIVER = "org.gjt.mm.mysql.Driver" ;
 7     private static final String DBURL = "jdbc:mysql://localhost:3306/test" ;
 8     private static final String DBUSER = "root" ;
 9     private static final String DBPASS = "123456" ;
10     
11     private static Connection conn = null ;
12     
13     //外部取得连接
14     public static Connection getConnection() throws Exception {
15         Class.forName(DBDRIVER) ;
16         conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS) ;
17         return conn ;
18     }
19     
20     //关闭连接
21     public static void close(ResultSet rs, Statement ps, Connection ct){
22         try {
23             if (rs!=null){
24                 rs.close() ;
25             }
26         } catch (SQLException e) {
27             e.printStackTrace();
28         }
29         try {
30             if (ps!=null){
31                 ps.close() ;
32             }
33         } catch (SQLException e) {
34             e.printStackTrace();
35         }
36         try {
37             if (ct!=null){
38                 ct.close() ;
39             }
40         } catch (SQLException e) {
41             e.printStackTrace();
42         }
43     }
44 }

 1 package fafa.shop.util;
 2 
 3 import java.sql.*;
 4 import java.util.ArrayList;
 5 
 6 public class SqlHelper {
 7     
 8     private static Connection ct = null ;
 9     private static PreparedStatement ps = null ;
10     private static ResultSet rs = null ;
11     
12     /**
13      * 执行sql查询  返回结果集
14      * @param sql
15      * @param param
16      * @return rs
17      */
18     public ResultSet executeQuery(String sql, String []param){
19          try {
20              //取得连接
21              ct = DBUtil.getConnection() ;
22              //sql预处理
23              ps = ct.prepareStatement(sql) ;
24              //如果参数存在，循环赋值
25              if (param!=null && !param.equals("")){
26                  for(int i=0; i<param.length; i++){
27                      ps.setString(i+1, param[i]) ;
28                  }
29              }
30              //执行sql
31              rs = ps.executeQuery() ;
32         } catch (Exception e) {    //异常抛出
33             e.printStackTrace() ;
34         }
35          //返回结果集
36          return rs ;
37      }
38      
39     /**
40      * 执行查询 返回集合
41      * @param sql
42      * @param param
43      * @return all 集合
44      */
45      public ArrayList<Object> executeQuery1(String sql, String []param){
46          //定义集合接收
47          ArrayList<Object> all = new ArrayList<Object>() ;
48          try {
49              //取得连接
50             ct = DBUtil.getConnection() ;
51             //预处理
52             ps = ct.prepareStatement(sql) ;
53             //如果存在 循环赋值
54             if (param!=null && !param.equals("")){
55                 for(int i=0; i<param.length; i++){
56                     ps.setString(i+1, param[i]) ;
57                 }
58             }
59             //执行sql语句 取得结果集
60             rs = ps.executeQuery() ;
61             //取得字段列表
62             ResultSetMetaData rsmd = rs.getMetaData() ;
63             //取得字段数量
64             int columnNum = rsmd.getColumnCount() ;
65             //循环取值
66             while(rs.next()){
67                 Object []objects = new Object[columnNum] ;
68                 for(int i=0; i<objects.length; i++){
69                     objects[i] = rs.getObject(i+1) ;//返回对象数组
70                 }
71                 //循环加入集合
72                 all.add(objects) ;
73             }
74         } catch (Exception e) {
75             e.printStackTrace();
76         }finally{
77             //关闭连接
78             DBUtil.close(rs, ps, ct) ;
79         }
80         //返回集合
81         return all;
82      }
83 }

2、用户需要登录 Servlet去接收并验证

 1 package fafa.shop.controller;
 2 
 3 import java.io.IOException;
 4 import java.util.ArrayList;
 5 
 6 import javax.servlet.*;
 7 import javax.servlet.http.*;
 8 
 9 import fafa.shop.doamin.User;
10 import fafa.shop.service.BookService;
11 import fafa.shop.service.MyCart;
12 import fafa.shop.service.UserService;
13 
14 @SuppressWarnings("serial")
15 public class GoHallUI extends HttpServlet {
16 
17     public void doGet(HttpServletRequest request, HttpServletResponse response)
18             throws ServletException, IOException {
19         request.setCharacterEncoding("GBK") ;
20         //取得登陆表单的数据
21         String userid = request.getParameter("userid") ;
22         String password = request.getParameter("password") ;
23         
24         //创建user对象，构造方法设置用户ID password
25         User user = new User(Integer.parseInt(userid), password) ;
26         
27         //使用UserService验证数据
28         UserService us = new UserService() ;
29         if (us.checkUser(user)){
30             //数据库验证成功后，写入session
31             request.getSession().setAttribute("loginUser", user) ;
32             //用户登录成功 就创建购物车 存入session
33             MyCart mycart = new MyCart() ;
34             request.getSession().setAttribute("mycart", mycart) ;
35             
36             //给hall.jsp 输出数据
37             BookService bookservice = new BookService() ;
38             ArrayList<?> all = bookservice.getAllBook() ;
39             request.setAttribute("all", all) ;
40             
41             //成功跳转  hall.jsp 购物大厅页
42             request.getRequestDispatcher("/WEB-INF/hall.jsp").forward(request, response) ;
43         }else{
44             //失败跳转 login.jsp 登陆页
45             request.setAttribute("error", "用户名或密码错误") ;
46             request.getRequestDispatcher("/WEB-INF/login.jsp").forward(request, response) ;
47         }
48     }
49 
50     public void doPost(HttpServletRequest request, HttpServletResponse response)
51             throws ServletException, IOException {
52         this.doGet(request, response) ;
53     }
54 }

3、user bean类和 userService CRUD类

 1 package fafa.shop.doamin;
 2 /**
 3  *  User Bean 
 4  * @author administrator
 5  */
 6 public class User {
 7     private int id ;
 8     private String username ;
 9     private String password ;
10     private String email ;
11     private String tel ;
12     private int grade ;
13     
14     public User(int id, String password) {
15         super();
16         this.id = id;
17         this.password = password;
18     }
19     public int getId() {
20         return id;
21     }
22     public void setId(int id) {
23         this.id = id;
24     }
25     public String getUsername() {
26         return username;
27     }
28     public void setUsername(String username) {
29         this.username = username;
30     }
31     public String getPassword() {
32         return password;
33     }
34     public void setPassword(String password) {
35         this.password = password;
36     }
37     public String getEmail() {
38         return email;
39     }
40     public void setEmail(String email) {
41         this.email = email;
42     }
43     public String getTel() {
44         return tel;
45     }
46     public void setTel(String tel) {
47         this.tel = tel;
48     }
49     public int getGrade() {
50         return grade;
51     }
52     public void setGrade(int grade) {
53         this.grade = grade;
54     }
55     
56 }

 1 package fafa.shop.service;
 2 
 3 import java.util.ArrayList;
 4 
 5 import fafa.shop.doamin.User;
 6 import fafa.shop.util.SqlHelper;
 7 
 8 public class UserService {
 9     
10     //验证用户
11     public boolean checkUser(User user) {
12         //到数据库验证
13         String sql = "SELECT id, username, password, email, grade FROM user WHERE username=? AND password=?" ;
14         String param[] = {user.getUsername(), user.getPassword()} ;
15         //取得查询后的结果集
16         ArrayList<?> all = (ArrayList<?>) new SqlHelper().executeQuery(sql, param) ;
17         if (all.size() == 0){
18             return false ;
19         }else{
20             Object []obj = (Object[]) all.get(0) ;
21             user.setId((Integer) obj[0]) ;
22             user.setUsername((String) obj[1]) ;
23             user.setTel((String) obj[3]) ;
24             user.setGrade((Integer) obj[4]) ;
25             return true ;
26         }
27     }
28 }

3、购物车类

 1 package fafa.shop.service;
 2 
 3 import java.util.*;
 4 
 5 import fafa.shop.doamin.Book;
 6 
 7 public class MyCart {
 8     //定义hashmap接收书
 9     HashMap<String, Book> hm = new HashMap<String, Book>() ;
10     
11     public void addBook2(String id){
12         if (hm.containsKey(id)){//判断此ID是否存在
13             Book book = hm.get(id) ; //其实拿出来的是前一本书 修改购买数量
14             int shoppingNum = book.getShoppingNum() ;
15             book.setShoppingNum(shoppingNum + 1) ;
16         }else{
17             hm.put(id, new BookService().getBookById(id)) ; //如果是第一本书则直接加入HashMap
18         }
19     }
20     
21     //添加书
22     public void addBook(String id, Book book){
23         if (hm.containsKey(id)){ //判断此ID是否存在
24             book = hm.get(id) ; //其实拿出来的是前一本书 修改购买数量
25             //如果购物车中存在这本书 ，那么则把购买数量加1
26             int shoppingNum = book.getShoppingNum() ;
27             book.setShoppingNum(shoppingNum + 1) ;
28         }else{
29             hm.put(id, book) ;
30         }
31     }
32     //删除书
33     public void delBook(String id){
34         hm.remove(id) ;
35      }
36     //更新书
37     public void updateBook(String id, String nums){
38         Book book = hm.get(id) ;
39         book.setShoppingNum(Integer.parseInt(nums)) ;
40         
41     }
42     
43     //显示购物车中的所有商品
44     public ArrayList<Book> showMycart(){
45         Iterator<String> iter = hm.keySet().iterator() ;
46         ArrayList<Book> all = new ArrayList<Book>() ;
47         while(iter.hasNext()){
48             String key = (String) iter.next() ;
49             Book book = hm.get(key) ;
50             all.add(book) ;
51         }
52         return all ;
53     }
54     
55     //计算总价
56     public float getTotalPrice(){
57         float totalPrice = 0.0f ;
58         Iterator<String> iterator = hm.keySet().iterator() ;
59         while(iterator.hasNext()){
60             String bookId = (String) iterator.next() ;
61             Book book = hm.get(bookId) ;
62             totalPrice += book.getPrice() * book.getShoppingNum() ;
63         }
64         return totalPrice;
65     }
66     
67     //清空购物车
68     public void clearBook(){
69         hm.clear() ;
70     }
71 }

4、购物大厅数据，book bean类和 bookService 类

 1 package fafa.shop.doamin;
 2 /**
 3  * Book bean 
 4  * @author administrator
 5  */
 6 public class Book {
 7     private int id ;
 8     private String name ;
 9     private String author ;
10     private String publishHouse ;
11     private float price ;
12     private int nums ;
13     private int shoppingNum = 1;  //购买数量
14     
15     public int getShoppingNum() {
16         return shoppingNum;
17     }
18     public void setShoppingNum(int shoppingNum) {
19         this.shoppingNum = shoppingNum;
20     }
21     public int getId() {
22         return id;
23     }
24     public void setId(int id) {
25         this.id = id;
26     }
27     public String getName() {
28         return name;
29     }
30     public void setName(String name) {
31         this.name = name;
32     }
33     public String getAuthor() {
34         return author;
35     }
36     public void setAuthor(String author) {
37         this.author = author;
38     }
39     public String getPublishHouse() {
40         return publishHouse;
41     }
42     public void setPublishHouse(String publishHouse) {
43         this.publishHouse = publishHouse;
44     }
45     public float getPrice() {
46         return price;
47     }
48     public void setPrice(float price) {
49         this.price = price;
50     }
51     public int getNums() {
52         return nums;
53     }
54     public void setNums(int nums) {
55         this.nums = nums;
56     }
57     
58 }

 1 package fafa.shop.service;
 2 
 3 import java.util.ArrayList;
 4 
 5 import fafa.shop.doamin.Book;
 6 import fafa.shop.util.SqlHelper;
 7 
 8 
 9 public class BookService {
10     public ArrayList<?> getAllBook(){
11         String sql = "SELECT * FROM book WHERE bname LIKE '%?%'" ;
12         String param[] = {""} ;
13         ArrayList<?> all = (ArrayList<?>) new SqlHelper().executeQuery(sql, param) ;
14         ArrayList<Book> newall = new ArrayList<Book>();
15         
16         for(int i=0; i<all.size(); i++){
17             Object obj[] = (Object[]) all.get(i) ;
18             Book book = new Book();
19             book.setId(Integer.parseInt(obj[0].toString())) ;
20             book.setName(obj[1].toString()) ;
21             book.setPublishHouse(obj[2].toString()) ;
22             book.setAuthor(obj[3].toString()) ;
23             book.setPrice(Float.parseFloat(obj[4].toString())) ;
24             book.setNums(Integer.parseInt(obj[5].toString())) ;
25             newall.add(book);
26         }
27         return newall;
28     }
29     
30     //根据ID 去一条数据 
31     public Book getBookById(String id){
32         String sql = "SELECT * FROM book WHERE id=?" ;
33         String param[] = {id} ;
34         ArrayList<?> all = (ArrayList<?>) new SqlHelper().executeQuery(sql, param) ;
35         Book book = new Book();
36         if (all.size() == 1){
37             Object []obj = (Object[])all.get(0) ;
38             book.setId(Integer.parseInt(obj[0].toString())) ;
39             book.setName(obj[1].toString()) ;
40             book.setPublishHouse(obj[2].toString()) ;
41             book.setAuthor(obj[3].toString()) ;
42             book.setPrice(Float.parseFloat(obj[4].toString())) ;
43             book.setNums(Integer.parseInt(obj[5].toString())) ;
44         }
45         return book;
46     }
47 }

5、用户点击购买，跳转到购物车界面购物车中的CRUD Servlet

 1 package fafa.shop.controller;
 2 
 3 import java.io.IOException;
 4 
 5 import javax.servlet.ServletException;
 6 import javax.servlet.http.HttpServlet;
 7 import javax.servlet.http.HttpServletRequest;
 8 import javax.servlet.http.HttpServletResponse;
 9 
10 import fafa.shop.service.MyCart;
11 
12 @SuppressWarnings("serial")
13 public class GoShowMyCart extends HttpServlet {
14     public void doGet(HttpServletRequest request, HttpServletResponse response)
15             throws ServletException, IOException {
16         request.setCharacterEncoding("GBK") ;
17         
18         //从Seesion中取出数据 到showMyCart.jsp页面显示 
19         MyCart mycart = (MyCart) request.getSession().getAttribute("mycart") ;
20         //把mycart中的书，输出到页面showMyCart.jsp
21         request.setAttribute("booklist", mycart.showMycart()) ;
22         //输出总价
23         request.setAttribute("totalPrice", mycart.getTotalPrice()) ;
24         //跳转到showMyCart.jsp
25         request.getRequestDispatcher("/WEB-INF/showMyCart.jsp").forward(request, response) ;
26         
27     }
28 
29     public void doPost(HttpServletRequest request, HttpServletResponse response)
30             throws ServletException, IOException {
31         this.doGet(request, response) ;
32     }
33 
34 }

 1 package fafa.shop.controller;
 2 import java.io.IOException;
 3 import javax.servlet.ServletException;
 4 import javax.servlet.http.HttpServlet;
 5 import javax.servlet.http.HttpServletRequest;
 6 import javax.servlet.http.HttpServletResponse;
 7 import fafa.shop.service.MyCart;
 8 
 9 /**
10  * 处理购物车请求
11  * @author administrator
12  *
13  */
14 @SuppressWarnings("serial")
15 public class ShoppingCLservlet extends HttpServlet {
16 
17     @Override
18     protected void doGet(HttpServletRequest req, HttpServletResponse resp)
19             throws ServletException, IOException {
20         req.setCharacterEncoding("GBK") ;
21         //获取处理类型
22         String type = req.getParameter("type") ;
23         
24         //判断类型
25         if (type.equals("del")){
26             String id = req.getParameter("id") ;
27             //获取购物车，并删除商品
28             MyCart mycart = (MyCart) req.getSession().getAttribute("mycart") ;
29             mycart.delBook(id) ;
30             //把数据也传递过去
31             req.setAttribute("booklist", mycart.showMycart()) ;
32             //输出总价
33             req.setAttribute("totalPrice", mycart.getTotalPrice()) ;
34             //跳转到购物车jsp页面
35             req.getRequestDispatcher("/WEB-INF/showMyCart.jsp").forward(req, resp) ;
36             
37         }else if(type.equals("add")){
38             //获取商品编号
39             String id = req.getParameter("id") ;
40             //取出购物车，并添加商品到购物车
41             MyCart mycart = (MyCart) req.getSession().getAttribute("mycart") ;
42             mycart.addBook2(id) ;
43             
44             //客户端跳转到 GoShowMyCart 控制器  然后准备数据 传输到 showMyCart.jsp 页面
45             resp.sendRedirect("/sp/GoShowMyCart");
46 
47         }else if (type.equals("update")){
48             String bookIds[] = req.getParameterValues("id") ;
49             String nums[] = req.getParameterValues("num") ;
50             //取出购物车，并更新数量
51             MyCart mycart = (MyCart) req.getSession().getAttribute("mycart") ;
52             for(int i=0; i<bookIds.length; i++){
53                 mycart.updateBook(bookIds[i], nums[i]) ;
54             }
55             //把mycart中的书，输出到页面showMyCart.jsp
56             req.setAttribute("booklist", mycart.showMycart()) ;
57             //输出总价
58             req.setAttribute("totalPrice", mycart.getTotalPrice()) ;
59             //跳转到购物车jsp页面
60             req.getRequestDispatcher("/WEB-INF/showMyCart.jsp").forward(req, resp) ;
61         }else if (type.equals("clear")){
62             //获取购物车，并删除商品
63             MyCart mycart = (MyCart) req.getSession().getAttribute("mycart") ;
64             mycart.clearBook() ;
65             //把数据也传递过去
66             req.setAttribute("booklist", mycart.showMycart()) ;
67             //输出总价
68             req.setAttribute("totalPrice", mycart.getTotalPrice()) ;
69             //跳转到购物车jsp页面
70             req.getRequestDispatcher("/WEB-INF/showMyCart.jsp").forward(req, resp) ;
71         }
72     }
73 
74     @Override
75     protected void doPost(HttpServletRequest req, HttpServletResponse resp)
76             throws ServletException, IOException {
77         super.doGet(req, resp);
78     }
79 }

6、生成订单，跳转到订单页面

 1 package fafa.shop.controller;
 2 import java.io.IOException;
 3 import java.util.ArrayList;
 4 
 5 import javax.servlet.ServletException;
 6 import javax.servlet.http.HttpServlet;
 7 import javax.servlet.http.HttpServletRequest;
 8 import javax.servlet.http.HttpServletResponse;
 9 
10 import fafa.shop.service.MyCart;
11 @SuppressWarnings("serial")
12 public class GoMyOrderServlet extends HttpServlet {
13     public void doGet(HttpServletRequest request, HttpServletResponse response)
14             throws ServletException, IOException {
15         request.setCharacterEncoding("GBK") ;
16         //取出购物车， 取得商品信息 和 价格 ， 并设置
17         MyCart mycart = (MyCart) request.getSession().getAttribute("mycart") ;
18         ArrayList<?> all = mycart.showMycart() ;
19         float totalPrice = mycart.getTotalPrice() ;
20         request.setAttribute("orderinfo", all) ;
21         request.setAttribute("tatalPrice", totalPrice) ;
22         
23         //跳转到 showMyOrder.jsp 显示订单信息
24         request.getRequestDispatcher("/WEB-INF/showMyOrder.jsp").forward(request, response) ;
25      }
26 
27     public void doPost(HttpServletRequest request, HttpServletResponse response)
28             throws ServletException, IOException {
29         this.doGet(request, response) ;
30     }
31 }

 1 package fafa.shop.service;
 2 
 3 import java.sql.*;
 4 import java.util.ArrayList;
 5 
 6 import fafa.shop.doamin.Book;
 7 import fafa.shop.doamin.User;
 8 import fafa.shop.util.DBUtil;
 9 
10 public class OrderService {
11     private Connection ct = null ;
12     private PreparedStatement ps = null ;
13     private ResultSet rs = null ;
14     
15     //下订单涉及到两张表， 且有关系
16     public boolean submitOrder(MyCart mycart, User user){
17         boolean flag = false ;
18         String sql = "INSERT INTO order VALUES(order_seq.nextval, ?, ?, sysdate)"; 
19         try{
20             ct = DBUtil.getConnection() ;        //取得连接
21             
22             //为了保证两张表的数据在提交时不发生错乱，所以必须升级事务隔离级别，为可串行化。
23             ct.setAutoCommit(false) ;            //设置非自动提交事务 ；
24             ct.setTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE) ;    //设置隔离级别为串行化
25             
26             ps = ct.prepareStatement(sql) ;        //预处理sql
27             ps.setInt(1, user.getId()) ;        //设置值
28             ps.setFloat(2, mycart.getTotalPrice()) ;//设置值
29             ps.executeUpdate() ;                //执行sql
30             
31             //得到刚刚插入订单表的订单号
32             sql = "SELECT order_seq FROM order" ;
33             ps = ct.prepareStatement(sql) ;
34             rs = ps.executeQuery() ; 
35             int orderId = 0 ;
36             if (rs.next()){
37                 orderId = rs.getInt(1) ;
38             }
39             //取得上面的 订单ID 生成订单细节表 
40             ArrayList<?> all = mycart.showMycart() ;
41             for(int i=0; i<all.size(); i++){
42                 Book book = (Book) all.get(i) ;
43                 sql = "INSERT INTO orderItem VALUES(orderItem_seq.nextval, ?, ?, ?)" ; 
44                 ps = ct.prepareStatement(sql) ;
45                 ps.setInt(1, orderId) ;
46                 ps.setInt(2, book.getId()) ;
47                 ps.setInt(3, book.getShoppingNum()) ;
48                 ps.executeUpdate() ;
49             }
50             
51             ct.commit() ;    //提交事务
52             flag = true ;
53         }catch(Exception e){
54             try {
55                 ct.rollback() ; //事务回滚
56             } catch (SQLException e1) {
57                 e1.printStackTrace();
58             }
59             e.printStackTrace() ;
60         }
61         
62         return flag ;
63     }
64 }

7、确认订单并发送邮件

 1 package fafa.shop.controller;
 2 import java.io.IOException;
 3 
 4 import javax.servlet.ServletException;
 5 import javax.servlet.http.HttpServlet;
 6 import javax.servlet.http.HttpServletRequest;
 7 import javax.servlet.http.HttpServletResponse;
 8 
 9 import fafa.shop.doamin.User;
10 import fafa.shop.mail.MailSenderInfo;
11 import fafa.shop.mail.SimpleMailSender;
12 import fafa.shop.service.MyCart;
13 import fafa.shop.service.OrderService;
14 
15 
16 @SuppressWarnings("serial")
17 public class SubmitOrderServlet extends HttpServlet {
18     public void doGet(HttpServletRequest request, HttpServletResponse response)
19             throws ServletException, IOException {
20         request.setCharacterEncoding("GBK") ;
21         //从Session中取出 购物车 和用户信息
22         MyCart mycart = (MyCart) request.getSession().getAttribute("mycart") ;
23         User user = (User) request.getSession().getAttribute("loginUser") ;
24         //实例化 OrderService 对象
25         OrderService orderservice = new OrderService() ;
26         //如果不成功  跳转错误页面  否则跳转 正确页面
27         if ( orderservice.submitOrder(mycart, user) == false ){
28             request.getRequestDispatcher("/WEB-INF/orderError.jsp") ;
29         }else{
30             // 这个类主要是设置邮件相关信息
31             MailSenderInfo mailInfo = new MailSenderInfo();    
32             mailInfo.setMailServerHost("smtp.163.com"); //代理发邮件的服务器地址
33             mailInfo.setMailServerPort("25");            //邮件服务器端口
34             mailInfo.setValidate(true);                    //是否验证
35             mailInfo.setUserName("dafa168@163.com");    //邮件账号
36             mailInfo.setPassword("**********");            //邮箱密码
37             mailInfo.setFromAddress("dafa168@163.com"); //发送邮件邮箱
38             mailInfo.setToAddress("dafa168@126.com");    //接收邮件邮箱
39             mailInfo.setSubject("设置测试邮箱标题 ");        //邮件标题
40             mailInfo.setContent("设置邮箱内容测试测试测试测试"); //邮件内容
41             
42             // 这个类主要来发送邮件
43             SimpleMailSender sms = new SimpleMailSender();
44             //sms.sendTextMail(mailInfo);// 发送文体格式
45             sms.sendHtmlMail(mailInfo);// 发送html格式
46             request.getRequestDispatcher("/WEB-INF/showMyOrder.jsp").forward(request, response) ;
47         }
48     }
49 
50     public void doPost(HttpServletRequest request, HttpServletResponse response)
51             throws ServletException, IOException {
52         this.doGet(request, response); 
53     }
54 }

下面应该跳转到支付界面，付款，以后开发过了就会补上来

需要研究啊

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原文地址：https://www.cnblogs.com/dafa/p/2770998.html