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;
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 } 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 ?} 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 } ?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 } 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Cookie23 ????????????????????????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 } ?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 }用户登录界面(1.8版本--网站框架改进)
原文地址：https://www.cnblogs.com/KSYoon/p/9435960.html