一，Java Web项目需要掌握的技术

　　·java语言

　　　　-|  JDBC

　　　　-|  Servlet

　　　　-|  JSP

　　　　-|  JavaBean

　　·面向对象分析设计思想

　　·设计模式和框架结构

　　·XML语言

　　·网页脚本语言

　　·开发工具

　　　　-|数据库

　　　　-|应用服务器

　　　　-|集成开发环境（IDE）

二.源代码：

1 package dao; 2  3 import java.util.List; 4  5 import model.*; 6 public interface IUserDao  7 { 8     public void add(User user); 9     public void delete(String username);10     public void update(User user);11     public User load(int id);12     public User load(String username);13     public List
      
        load();14 }
      

1 package dao;  2   3 import java.sql.Connection;  4 import java.sql.PreparedStatement;  5 import java.sql.ResultSet;  6 import java.sql.SQLException;  7 import java.util.ArrayList;  8 import java.util.List;  9  10 import Util.*; 11 import model.*; 12  13 public class UserDaoImpl implements IUserDao 14 { 15     @Override 16     public void add(User user)  17     { 18         Connection connection=Util.getConnection(); 19         String sql="select count(*) from t_user where username=?"; 20         PreparedStatement preparedStatement=null; 21         ResultSet resultSet=null; 22         try { 23             preparedStatement=connection.prepareStatement(sql); 24             preparedStatement.setString(1, user.getUsername()); 25             resultSet=preparedStatement.executeQuery(); 26             while(resultSet.next()) 27             { 28                 if(resultSet.getInt(1)>0) 29                 { 30                     throw new UserException("用户已存在!"); 31                 } 32             } 33         } catch (SQLException e) { 34             // TODO Auto-generated catch block 35             e.printStackTrace(); 36         } 37         sql="insert into t_user(username,password) value(?,?)"; 38         try { 39             preparedStatement=connection.prepareStatement(sql); 40             preparedStatement.setString(1, user.getUsername()); 41             preparedStatement.setString(2, user.getPassword()); 42             preparedStatement.executeUpdate(); 43         } catch (SQLException e) { 44             // TODO Auto-generated catch block 45             e.printStackTrace(); 46         }finally 47         { 48             Util.close(connection); 49             Util.close(preparedStatement); 50             Util.close(resultSet); 51         } 52     } 53  54     @Override 55     public void delete(String username) { 56         Connection connection=Util.getConnection(); 57         String sql="delete from t_user where username = ?"; 58         PreparedStatement preparedStatement=null; 59         try { 60             preparedStatement=connection.prepareStatement(sql); 61             preparedStatement.setString(1, username); 62             preparedStatement.executeUpdate(); 63         } catch (SQLException e) { 64             // TODO Auto-generated catch block 65             e.printStackTrace(); 66         }finally 67         { 68             Util.close(connection); 69             Util.close(preparedStatement); 70         }     71     } 72  73     @Override 74     public void update(User user) { 75         Connection connection=Util.getConnection(); 76         String sql="update t_user set password = ? where username = ?"; 77         PreparedStatement preparedStatement=null; 78         try { 79             preparedStatement=connection.prepareStatement(sql); 80             preparedStatement.setString(1, user.getPassword()); 81             preparedStatement.setString(2, user.getUsername()); 82             preparedStatement.executeUpdate(); 83         } catch (SQLException e) { 84             // TODO Auto-generated catch block 85             e.printStackTrace(); 86         }finally 87         { 88             Util.close(connection); 89             Util.close(preparedStatement); 90         } 91     } 92  93     @Override 94     public User load(int id)  95     { 96         Connection connection=Util.getConnection(); 97         String sql="select * from t_user where id=?"; 98         User user=null; 99         PreparedStatement preparedStatement=null;100         ResultSet resultSet=null;101         try {102             preparedStatement=connection.prepareStatement(sql);103             preparedStatement.setInt(1, id);104             resultSet=preparedStatement.executeQuery();105             while(resultSet.next())106             {107                 user=new User();108                 user.setId(id);109                 user.setUsername(resultSet.getString("username"));110                 user.setPassword(resultSet.getString("password"));111             }112         } catch (SQLException e) {113             // TODO Auto-generated catch block114             e.printStackTrace();115         }finally116         {117             Util.close(connection);118             Util.close(preparedStatement);119             Util.close(resultSet);120         }121         return user;122     }123 124     @Override125     public User load(String username) 126     {127         Connection connection=Util.getConnection();128         String sql="select * from t_user where username=?";129         User user=null;130         PreparedStatement preparedStatement=null;131         ResultSet resultSet=null;132         try {133             preparedStatement=connection.prepareStatement(sql);134             preparedStatement.setString(1, username);135             resultSet=preparedStatement.executeQuery();136             while(resultSet.next())137             {138                 user=new User();139                 user.setId(resultSet.getInt("id"));140                 user.setUsername(username);141                 user.setPassword(resultSet.getString("password"));142             }143         } catch (SQLException e) {144             // TODO Auto-generated catch block145             e.printStackTrace();146         }finally147         {148             Util.close(connection);149             Util.close(preparedStatement);150             Util.close(resultSet);151         }152         return user;153     }154 155     @Override156     public List
      
        load() 157     {158         Connection connection=Util.getConnection();159         String sql="select * from t_user ";160         PreparedStatement preparedStatement=null;161         ResultSet resultSet=null;162         List
       
         users=new ArrayList
        
         ();163         User user=null;164         try165         {166             preparedStatement=connection.prepareStatement(sql);167             resultSet=preparedStatement.executeQuery();168             while(resultSet.next())169             {170                 user=new User();171                 user.setId(resultSet.getInt("id"));172                 user.setUsername(resultSet.getString("username"));173                 user.setPassword(resultSet.getString("password"));174                 users.add(user);175             }176         }catch (SQLException e) {177             // TODO Auto-generated catch block178             e.printStackTrace();179         }finally180         {181             Util.close(connection);182             Util.close(preparedStatement);183             Util.close(resultSet);184         }185         return users;186         }187 }
        
       
      

1 package model; 2  3 public class User  4 { 5     private int id; 6     private String username; 7     private String password; 8     public int getId() { 9         return id;10     }11     public void setId(int id) {12         this.id = id;13     }14     public String getUsername() {15         return username;16     }17     public void setUsername(String username) {18         this.username = username;19     }20     public String getPassword() {21         return password;22     }23     public void setPassword(String password) {24         this.password = password;25     }26 27 }

1 package model; 2  3 public class UserException extends RuntimeException{ 4  5     /** 6      *  7      */ 8     private static final long serialVersionUID = 1L; 9 10     public UserException() {11         super();12         // TODO Auto-generated constructor stub13     }14 15     public UserException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) {16         super(message, cause, enableSuppression, writableStackTrace);17         // TODO Auto-generated constructor stub18     }19 20     public UserException(String message, Throwable cause) {21         super(message, cause);22         // TODO Auto-generated constructor stub23     }24 25     public UserException(String message) {26         super(message);27         // TODO Auto-generated constructor stub28     }29 30     public UserException(Throwable cause) {31         super(cause);32         // TODO Auto-generated constructor stub33     }34 35 36 }

1 <%@page import="dao.UserDaoImpl"%> 2 <%@page import="model.*"%> 3 <%@page import="Util.*"%> 4 <%@ page language="java" contentType="text/html; charset=UTF-8" 5     pageEncoding="UTF-8"%> 6  7  8 
       9 <%10     String username=request.getParameter("username");11     String password=request.getParameter("password");12     String repassword=request.getParameter("repassword");13     if(username==null||"".equals(username.trim()))14     {15         request.setAttribute("error","用户名不能为空！");16 %>17     
      18 <%19     }20     if(password==null||"".equals(password.trim()))21     {22         request.setAttribute("error","密码不能为空！");23 %>24     
      25 <%26     }27     if(repassword==null||"".equals(repassword.trim()))28     {29         request.setAttribute("error","再次输入密码以示确认！");30 %>31     
      32 <%33     }34     if(!password.trim().equals(repassword.trim()))35     {36         request.setAttribute("error","两次输入的密码不一致。请确认后再进行操作！");37 %>38     
      39 <%40     }41     User user=new User();42     user.setUsername(username);43     user.setPassword(password);44     UserDaoImpl userDao=new UserDaoImpl();45     try46     {47     userDao.add(user);48 %>49     
用户保存成功！
50 <%51     }catch(UserException e)52     {53 %>54     
error:<%=e.getMessage() %>
55 <%56     }57     %>           58 

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%>    
              
      
        
       
                    
         
                      
用户名：
                      
                            
                     
                     
                      
密码：
                      
                            
                     
                     
                      
确认密码：
                      
                            
                     
                     
                      
                                            
                     
                
       
    
      
    
    <%    if(request.getAttribute("error")!=null)    {    %>    
<%=request.getAttribute("error") %>
    <%    }    %>

1 <%@page import="dao.*"%> 2 <%@page import="model.*"%> 3 <%@page import="Util.*"%> 4 <%@ page language="java" contentType="text/html; charset=UTF-8" 5     pageEncoding="UTF-8"%> 6  7  8 
       9 <%10     String username=request.getParameter("username");11     String password=request.getParameter("password");12     UserDaoImpl userDao=new UserDaoImpl();13     User user=null;14     user=userDao.load(username);    15     if(user==null)16     {17         request.setAttribute("error", "您要删除的用户不存在");18 %>19 
      20 <%21     }22     if(!user.getPassword().equals(password))23     {24         request.setAttribute("error", "您输入的密码不正确，无权删除该用户！");25 %>26 
      27 <%28     }29     userDao.delete(username);30     %>31     
学号为<%=user.getUsername() %>的用户已经被删除！
32 

1 <%@ page language="java" contentType="text/html; charset=UTF-8" 2     pageEncoding="UTF-8"%> 3  4  5  6     
       7      8  9 10     
      
       11         
       
        12             
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29         
        
         
          
请输入要删除的用户名：
          
15                 16             
         
         
          
该用户的密码为：
          
21                 22             
         
         
          
26                 27             
         
        
       
30     
      
31     
32     <%33     if(request.getAttribute("error")!=null)34     {35     %>36     
<%=request.getAttribute("error") %>
37     <%38     }39     %>40 41 

1 <%@page import="dao.*"%> 2 <%@page import="model.*"%> 3 <%@page import="Util.*"%> 4 <%@ page language="java" contentType="text/html; charset=UTF-8" 5     pageEncoding="UTF-8"%> 6  7  8 
       9 <%    10     String username=request.getParameter("username");11     String password=request.getParameter("password");12     if(username==null||"".equals(username.trim()))13     {14         request.setAttribute("error","用户名不能为空！");15 %>16     
      17 <%18     }19     if(password==null||"".equals(password.trim()))20     {21         request.setAttribute("error","密码不能为空！");22 %>23     
      24 <%25     }26     User user=null;27     UserDaoImpl userDao=new UserDaoImpl();28     user = userDao.load(username);29     if(user==null)30     {31         request.setAttribute("error","该用户名不存在！");32 %>33     
      34 <%35     }36     if(!password.equals(user.getPassword()))37     {38         request.setAttribute("error","密码错误！");39 %>40     
      41 <%42     }43     else44     {45 %>46     
登录成功！
47     用户注册48     删除用户49     修改密码50     查询用户51 <%52     }53 %>54 

1 <%@ page language="java" contentType="text/html; charset=UTF-8" 2     pageEncoding="UTF-8"%> 3  4  5  6     
       7  8  9 10   
      
       11         
       
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27             
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31             
32         
        
         
          
用户名：
          
15                 16             
         
         
          
密码：
          
21                 22             
          
24                 修改密码25             
         
         
          
29                 30             
         
        
       
33   
      
34   
35   <%36     if(request.getAttribute("error")!=null)37     {38     %>39     
<%=request.getAttribute("error") %>
40     <%41     }42     %>43 44 

1 <%@page import="dao.*"%> 2 <%@page import="model.*"%> 3 <%@page import="Util.*"%> 4 <%@ page language="java" contentType="text/html; charset=UTF-8" 5     pageEncoding="UTF-8"%> 6  7  8 
       9 10 11 <%12     String username=request.getParameter("username");13     if(username==null||"".equals(username.trim()))14     {15         request.setAttribute("error", "查询内容不能为空！");16 %>17     
      18 <%19     }20     User user=null;21     UserDaoImpl userDao=new UserDaoImpl();22     user=userDao.load(username);23     if(user==null)24     {25         request.setAttribute("error", "您查找的用户不存在！");26 %>27     
      28 <%29     }30     else31     {32 %>33     
查询结果为：编号:<%=user.getId() %>学号：<%=user.getUsername() %>密码：<%=user.getPassword() %>
34 <%35     }36 %>37 

1 <%@ page language="java" contentType="text/html; charset=UTF-8" 2     pageEncoding="UTF-8"%> 3  4  5  6     
       7      8  9     
      
       10       
       
        11       
          12       
13       
    16       
17       
          18       
21       
 22       
        
         
          
请输入您要搜索的用户名：
          
14           15       
         
         
          
19           20       
         
        
       
23     
      
24      <%25     if(request.getAttribute("error")!=null)26     {27     %>28     
<%=request.getAttribute("error") %>
29     <%30     }31     %>32 

1 <%@page import="dao.*"%> 2 <%@page import="model.*"%> 3 <%@page import="Util.*"%> 4 <%@ page language="java" contentType="text/html; charset=UTF-8" 5     pageEncoding="UTF-8"%> 6  7  8 
       9 <%10     String username=request.getParameter("username");11     String password=request.getParameter("password");12     String newpassword=request.getParameter("newpassword");13     String newrepassword=request.getParameter("newrepassword");14     if(username==null||"".equals(username.trim()))15     {16         request.setAttribute("error","请输入要修改的用户名！");17 %>18     
      19 <%20     }21     if(password==null||"".equals(password.trim()))22     {23         request.setAttribute("error","原密码不能为空！！");24 %>25     
      26 <%27     }28     if(newpassword==null||"".equals(newpassword.trim()))29     {30         request.setAttribute("error","新密码不能为空！");31 %>32     
      33 <%34     }35     if(newrepassword==null||"".equals(newrepassword.trim()))36     {37         request.setAttribute("error","必须再次输入新密码，以免出现错误！");38 %>39     
      40 <%41     }42     User user=new User();43     UserDaoImpl userDao=new UserDaoImpl();44     user=userDao.load(username);45     if(user==null)46     {47         request.setAttribute("error","该用户不存在，请重新输入。");48 %>49     
      50 <%51     }52     if(!user.getPassword().equals(password))53     {54         request.setAttribute("error", "原密码不正确，无法修改！");55 %>56     
      57 <%58     }59     if(!newpassword.equals(newrepassword))60     {61         request.setAttribute("error", "两次输入的新密码不一致，请确认后再操作，修改失败！");62 %>63     
      64 <%65     }66         user.setUsername(username);67         user.setPassword(newpassword);68         userDao.update(user);69 %>70     
用户修改成功！
          71 

1 <%@ page language="java" contentType="text/html; charset=UTF-8" 2     pageEncoding="UTF-8"%> 3  4  5  6     
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41             
42         
        
         
          
要进行修改的用户名：
          
15                 16             
         
         
          
原密码：
          
21                 22             
         
         
          
新密码：
          
27                 28             
         
         
          
请再次输入密码：
          
33                 34             
         
         
          
38                 39                 40             
         
        
       
43     
      
44     <%45     if(request.getAttribute("error")!=null)46     {47     %>48     
<%=request.getAttribute("error") %>
49     <%50     }51     %>52 53 

1 package Util; 2  3  4 import java.sql.Connection; 5 import java.sql.DriverManager; 6 import java.sql.PreparedStatement; 7 import java.sql.ResultSet; 8 import java.sql.SQLException; 9 10 public class Util {11     public  static  Connection getConnection() {12         13             try {14                 Class.forName("com.mysql.jdbc.Driver").newInstance();15             } catch (InstantiationException e1) {16                 // TODO Auto-generated catch block17                 e1.printStackTrace();18             } catch (IllegalAccessException e1) {19                 // TODO Auto-generated catch block20                 e1.printStackTrace();21             } catch (ClassNotFoundException e1) {22                 // TODO Auto-generated catch block23                 e1.printStackTrace();24             }25         String user = "root";26         String password = "root";27         String url = "jdbc:mysql://localhost:3306/jaovo_msg";28         Connection connection = null;29         try {30              connection = DriverManager.getConnection(url,user,password);31         } catch (SQLException e) {32             // TODO Auto-generated catch block33             e.printStackTrace();34         }35         return connection;36     }37     public static void close(Connection connection ) {38         try {39             if (connection != null) {40                 connection.close();41             }42             43         } catch (SQLException e) {44             // TODO Auto-generated catch block45             e.printStackTrace();46         }47     }48     public static void close(PreparedStatement preparedStatement ) {49         try {50             if (preparedStatement != null) {51                 preparedStatement.close();52             }53             54         } catch (SQLException e) {55             // TODO Auto-generated catch block56             e.printStackTrace();57         }58     }59     public static void close(ResultSet resultSet ) {60         try {61             if (resultSet != null) {62                 resultSet.close();63             }64             65         } catch (SQLException e) {66             // TODO Auto-generated catch block67             e.printStackTrace();68         }69     }70     71 }

 

课堂测试完成了

 

三.学习目标

　　　　能自己独立做一个网站

　　　　时间计划，每周将花十个小时以上来学习这门课