用户登录界面(1.8版本--网站框架改进)

1.创建数据库db_user与表users

 1 CREATE DATABASE db_user CHARACTER SET utf8;
 2 
 3 CREATE TABLE users (
 4     userid TINYINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
 5     username varchar(20),
 6     passwd varchar(20),
 7     email varchar(30),
 8     priority int
 9 );
10 
11 DROP TABLE users;
12 
13 SELECT * FROM users;
14 
15 INSERT INTO users(username,passwd,email,priority) VALUES('admin','admin','admin@sohu.com',1);
16 INSERT INTO users(username,passwd,email,priority) VALUES('shunping','shunping','shunping@sohu.com',1);
17 INSERT INTO users(username,passwd,email,priority) VALUES('tester1','tester2','tester1@sohu.com',5);
18 INSERT INTO users(username,passwd,email,priority) VALUES('tester2','tester2','tseter2@sohu.com',5);
19 INSERT INTO users(username,passwd,email,priority) VALUES('tester3','tester3','tester3@sohu.com',5);
20 INSERT INTO users(username,passwd,email,priority) VALUES('tester4','tester4','tester4@sohu.com',5);
21 INSERT INTO users(username,passwd,email,priority) VALUES('tester5','tester5','tester5@sohu.com',5);
22 INSERT INTO users(username,passwd,email,priority) VALUES('tester6','tester6','tester6@sohu.com',5);
23 INSERT INTO users(username,passwd,email,priority) VALUES('tester7','tester7','tester7@sohu.com',5);
24 INSERT INTO users(username,passwd,email,priority) VALUES('tester8','tester8','tester8@sohu.com',5);
25 
26 //快速增加记录
27 INSERT INTO users(username,passwd,email,priority) SELECT username,passwd,email,priority FROM users;
28 
29 SELECT COUNT(*) FROM users;

Database

2.登录界面

 1 package com.tsinghua;
 2 
 3 import javax.servlet.http.*;
 4 import java.io.*;
 5 
 6 public class Login3 extends HttpServlet {
 7     public void doGet(HttpServletRequest req,HttpServletResponse res)  {
 8         try {
 9             res.setContentType("text/html;charset=utf8");
10             PrintWriter pw = res.getWriter();
11             String info1 = req.getParameter("info1");
12             String info3 = req.getParameter("info3");
13             pw.println("<html>");
14             pw.println("<body>");
15             //用户尚未登录提醒
16             if(info1!=null) {
17                 pw.println("<span>您还没有登录</span>");    
18             }
19             if(info3 != null) {
20                 pw.println("<span>您的用户名或密码错误</span>");    
21             }
22             pw.println("<h1>用户登录</h1>");
23             pw.println("<form action=loginCl3>");
24             pw.println("用户名:<input type=text name=username><br/>");
25             pw.println("密码:<input type=pasword name=passwd><br/>");
26             pw.println("<input type=checkbox name=checked value=2>两周之内不需要登录<br/>");
27             pw.println("<input type=submit value=login>");
28             pw.println("</form>");
29             pw.println("</body>");
30             pw.println("</html>");
31                 
32         }catch(Exception ex) {
33             ex.printStackTrace();    
34         }    
35     }
36     public void doPost(HttpServletRequest req,HttpServletResponse res)  {
37         this.doGet(req,res);    
38     }    
39 }

Login3.java

3.数据库连接

 1 package com.tsinghua;
 2  
 3 import java.sql.*;
 4  
 5 public class ConnDB {
 6      private Connection con = null;
 7      public Connection getConn() {
 8          try {
 9              Class.forName("com.mysql.jdbc.Driver");
10              con = DriverManager.getConnection("jdbc:mysql://localhost:3306/db_user","root","");
11          }catch(Exception ex) {
12              ex.printStackTrace();
13          }    
14          return con;
15      }        
16  }

ConnDB.java

4.映射表users

 1 //与表users一一映射
 2 package com.tsinghua;
 3 
 4 import java.sql.*;
 5 
 6 public class UserBean {
 7     private int userId;
 8     private String userName;
 9     private String passwd;
10     private String email;
11     private int priority;
12     public void setUserId(int userId) {
13         this.userId = userId;    
14     }        
15     public int getUserId() {
16         return     this.userId;
17     }
18     public void setUserName(String userName) {
19         this.userName = userName;    
20     }
21     public String getUserName() {
22         return this.userName;    
23     }
24     public void setPasswd(String passwd) {
25         this.passwd = passwd;    
26     }
27     public String getPasswd() {
28         return this.passwd;    
29     }
30     public void setEmail(String email) {
31         this.email = email;    
32     }
33     public String getEmail() {
34         return this.email;    
35     }
36     public void setPriority(int priority) {
37         this.priority = priority;
38     }
39     public int getPriority() {
40         return this.priority;    
41     }
42 }

UserBean.java

5.sql语句处理,操作表users

  1 //处理users表--->操作UserBean
  2 //业务逻辑处理
  3 
  4 package com.tsinghua;
  5 
  6 import java.sql.*;
  7 import java.util.*;
  8 import com.tsinghua.*;
  9 
 10 public class UserBeanCl {
 11     private Connection ct=null;
 12     private PreparedStatement ps=null;
 13     private ResultSet rs=null;
 14     private int pageCount=0;
 15     
 16     public int getPageCount() {
 17         return this.pageCount; 
 18     }
 19     
 20     public ArrayList getResultByPage(int pageNow,int pageSize) {
 21         
 22         //将数据库中记录分页 
 23         ArrayList arraylist = new ArrayList();
 24         try {
 25             int rowCount=0;
 26             ConnDB cd = new ConnDB();
 27             ct = cd.getConn();
 28             ps = ct.prepareStatement("select count(*) from users");
 29             rs = ps.executeQuery();
 30             if(rs.next()) {
 31                 rowCount = rs.getInt(1);
 32             }
 33             //计算pageCount
 34             if(rowCount % pageSize == 0) {
 35                 pageCount = rowCount / pageSize;    
 36             }else {
 37                 pageCount = rowCount / pageSize + 1;    
 38             }
 39          
 40             ps = ct.prepareStatement("select * from users limit ?,?");
 41             ps.setInt(1,(pageNow-1)*pageSize);
 42             ps.setInt(2,pageSize);
 43             rs = ps.executeQuery();
 44             if(rs.next()) {
 45                 UserBean ub = new UserBean();
 46                 ub.setUserId(rs.getInt(1));
 47                 ub.setUserName(rs.getString(2));
 48                 ub.setPasswd(rs.getString(3));
 49                 ub.setEmail(rs.getString(4));
 50                 ub.setPriority(rs.getInt(5));
 51                 arraylist.add(ub);    
 52             }
 53              
 54         }catch(Exception ex) {
 55             ex.printStackTrace();
 56         }finally {
 57             this.close();
 58         }
 59         return arraylist;
 60     }
 61                 
 62     //验证用户
 63     public boolean checkUser(String user,String pass) {
 64         boolean bool = false;
 65         try {
 66             ConnDB cd = new ConnDB();
 67             ct = cd.getConn();
 68             ps = ct.prepareStatement("select passwd from users where username=?");
 69             ps.setString(1,user);
 70             rs=ps.executeQuery();
 71             if(rs.next()) {
 72                 String sPasswd = rs.getString(1);
 73                 if(sPasswd.equals(pass)) {
 74                     bool=true;
 75                 }    
 76             }
 77         }catch(Exception ex) {
 78             ex.printStackTrace();    
 79         }finally {
 80             this.close(); 
 81         }
 82         return bool;    
 83     }
 84     public void close() {
 85         try {
 86             if(rs!=null) {
 87                 rs.close();    
 88                 rs=null;
 89             }    
 90             if(ps!=null) {
 91                 ps.close();
 92                 ps=null;    
 93             }
 94             if(ct!=null) {
 95                 ct.close();    
 96                 ct=null;
 97             }
 98         }catch(Exception ex) {
 99             ex.printStackTrace();    
100         }    
101     }
102         
103 }

UserBeanCl.java

6.业务逻辑处理

 1 package com.tsinghua;
 2 
 3 import javax.servlet.http.*;
 4 import java.io.*;
 5 import java.sql.*;
 6 import com.tsinghua.*;
 7 
 8 public class LoginCl3 extends HttpServlet {
 9     public void doGet(HttpServletRequest req,HttpServletResponse res) {
10         
11         try {
12             String user = req.getParameter("username");
13             String pass = req.getParameter("passwd");
14              
15              //检验用户
16              UserBeanCl ubc = new UserBeanCl();
17              if(ubc.checkUser(user,pass)){
18                   
19                     String checked = req.getParameter("checked");
20                     if(checked!=null) {
21                      
22                         //创建Cookie
23                         Cookie username = new Cookie("myName",user);
24                         Cookie passwd = new Cookie("myPasswd",pass);
25                         //设置存在时间
26                         username.setMaxAge(14*24*60*60);
27                         passwd.setMaxAge(14*24*60*60);
28                         //将Cookie回写到客户端
29                         res.addCookie(username);
30                         res.addCookie(passwd);
31                     }
32                     
33                     
34                      HttpSession hs = req.getSession(true);
35                     //添加session属性
36                     hs.setAttribute("uname",user);
37                     //设置存在时间
38                     hs.setMaxInactiveInterval(20);
39                      
40                     
41                     //跳转到欢迎页面
42                     res.sendRedirect("wel3?user="+user);    
43                  
44              }else {
45                  res.sendRedirect("login3?info3=err3");    
46              }
47         }catch(Exception ex) {
48             ex.printStackTrace();    
49         } 
50     }
51     public void doPost(HttpServletRequest req,HttpServletResponse res) {
52         this.doGet(req,res);
53     }    
54 }

LoginCl3.java

7.欢迎界面

  1 package com.tsinghua;
  2 import javax.servlet.http.*;
  3 import java.io.*;
  4 import java.sql.*;
  5 import java.util.*;
  6 import com.tsinghua.*;
  7 
  8 public class Wel3 extends HttpServlet {
  9     public void doGet(HttpServletRequest req,HttpServletResponse res) {
 10         //数据库
 11         Connection con = null;
 12         PreparedStatement ps = null;
 13         ResultSet rs = null;
 14         try {
 15             //html格式声明
 16             res.setContentType("text/html;charset=utf8"); 
 17             //分页 
 18             int pageSize=3;   //每页记录数     
 19             int pageNow=1;    //希望当前页数
 20             
 21             String user="";
 22             String pass="";
 23             
 24             //动态的接收pageNow    
 25             String sPageNow = req.getParameter("pageCur");
 26             if(sPageNow!=null) {
 27                 pageNow = Integer.parseInt(sPageNow);    
 28             }
 29             
 30                         
 31             PrintWriter pw = res.getWriter();
 32             //获取session属性
 33             HttpSession hs = req.getSession(true);
 34             String name = (String)hs.getAttribute("uname");
 35             
 36             //session不存在
 37             if(name==null) {
 38                 //检测是否有Cookie信息
 39                 Cookie []allCookies = req.getCookies();
 40                 if(allCookies != null) {
 41                     for(int i=0;i<allCookies.length;i++) {
 42                         Cookie temp = allCookies[i];
 43                         if(temp.getName().equals("myName")) {
 44                             user = temp.getValue();    
 45                         }else if(temp.getName().equals("myPasswd")) {
 46                             pass = temp.getValue();    
 47                         }
 48                     }
 49                     if(user.equals("")&&pass.equals("")) {
 50                         res.sendRedirect("loginCl3?username="+user+"&passwd="+pass);
 51                     }else {
 52                         //跳转登陆页面,提醒用户未登录
 53                         res.sendRedirect("login3?info1=err1");    
 54             
 55                     }
 56                 } 
 57             }
 58              
 59             UserBeanCl ubc = new UserBeanCl();
 60             ArrayList arraylist = ubc.getResultByPage(pageNow,pageSize);
 61             int pageCount = ubc.getPageCount(); 
 62              
 63             //欢迎用户(用户名)
 64             pw.println("Welcome your coming,"+name+"<br/>");
 65             //图片
 66             pw.println("<img width=100px height=100px src=imgs/KSYoon.jpg>");
 67             //输出分页后users表中信息
 68             pw.println("<table border=1>");
 69             pw.println("<tr>");
 70             pw.println("<th>userid</th>");
 71             pw.println("<th>username</th>");
 72             pw.println("<th>passwd</th>");
 73             pw.println("<th>email</th>");
 74             pw.println("<th>priority</th>");
 75             pw.println("</tr>");
 76              
 77             for(int i=0;i<arraylist.size();i++) {
 78                 UserBean ub = (UserBean)arraylist.get(i);
 79                 pw.println("<tr>");
 80                 pw.println("<td>"+ub.getUserId()+"</td>");
 81                 pw.println("<td>"+ub.getUserName()+"</td>");
 82                 pw.println("<td>"+ub.getPasswd()+"</td>");
 83                 pw.println("<td>"+ub.getEmail()+"</td>");
 84                 pw.println("<td>"+ub.getPriority()+"</td>");
 85                 pw.println("</tr>");    
 86             }
 87             
 88             pw.println("</table>");
 89             
 90             //上一页
 91             if(pageNow!=1) {
 92                 pw.println("<a href=wel3?pageCur="+(pageNow-1)+">上一页</a>");    
 93             }
 94             
 95             //页数链接
 96             for(int i=pageNow;i<pageNow+10;i++) {
 97                 //想要显示的当前页
 98                 pw.println("<a href=wel3?pageCur="+i+">"+i+"</a>");
 99             }
100              
101             //下一页
102             if(pageNow!= pageCount) {
103                 pw.println("<a href=wel3?pageCur="+(pageNow+1)+">下一页</a>");    
104             }
105         }catch(Exception ex) {
106             ex.printStackTrace();    
107         } 
108     }
109     public void doPost(HttpServletRequest req,HttpServletResponse res) {
110         this.doGet(req,res);    
111     }    
112 }

Wel3.java

8.servlet部署

 1 <servlet>
 2     <servlet-name>login3</servlet-name>
 3     <servlet-class>com.tsinghua.Login3</servlet-class>
 4   </servlet>
 5   <servlet-mapping>
 6     <servlet-name>login3</servlet-name>
 7     <url-pattern>/login3</url-pattern>
 8   </servlet-mapping>
 9 
10   <servlet>
11     <servlet-name>loginCl3</servlet-name>
12     <servlet-class>com.tsinghua.LoginCl3</servlet-class>
13   </servlet>
14   <servlet-mapping>
15     <servlet-name>loginCl3</servlet-name>
16     <url-pattern>/loginCl3</url-pattern>
17   </servlet-mapping>
18 
19   <servlet>
20     <servlet-name>wel3</servlet-name>
21     <servlet-class>com.tsinghua.Wel3</servlet-class>
22   </servlet>
23   <servlet-mapping>
24     <servlet-name>wel3</servlet-name>
25     <url-pattern>/wel3</url-pattern>
26   </servlet-mapping>
27 
28  <servlet>
29     <servlet-name>connDB</servlet-name>
30     <servlet-class>com.tsinghua.ConnDB</servlet-class>
31   </servlet>
32   <servlet-mapping>
33     <servlet-name>connDB</servlet-name>
34     <url-pattern>/connDB</url-pattern>
35   </servlet-mapping>
36 
37   <servlet>
38     <servlet-name>userBean</servlet-name>
39     <servlet-class>com.tsinghua.UserBean</servlet-class>
40   </servlet>
41   <servlet-mapping>
42     <servlet-name>userBean</servlet-name>
43     <url-pattern>/userBean</url-pattern>
44   </servlet-mapping>
45 
46   <servlet>
47     <servlet-name>userBeanCl</servlet-name>
48     <servlet-class>com.tsinghua.UserBeanCl</servlet-class>
49   </servlet>
50   <servlet-mapping>
51     <servlet-name>userBeanCl</servlet-name>
52     <url-pattern>/userBeanCl</url-pattern>
53   </servlet-mapping>