一个简单的servlet程序（处理用户登陆、操作数据库）
数据库用的是mysql。
最近在学servlet，顺便把代码共享下。
这个servlet程序主要功能是，通过数据库查找验证用户，以及进行简单的管理，如添加、删除。
Login.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 import java.util.Date; 5 import java.text.DateFormat; 6 import java.text.SimpleDateFormat; 7 import java.net.*; 8 import java.io.*; 9 10 public class Login extends HttpServlet{ 11 12 public void doGet(HttpServletRequest req,HttpServletResponse res){ 13 14 //-------------------------------------------------------------------------------- 15 try{ 16 String ip=req.getRemoteAddr(); 17 this.getServletContext().setAttribute("ip",ip); 18 19 FileWriter fw=new FileWriter("d:\\ip.txt",true); 20 BufferedWriter bw=new BufferedWriter(fw); 21 //获取当前时间 22 Date dt=new Date();//如果不需要格式,可直接用dt,dt就是当前系统时间 23 DateFormat df = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");//设置显示格式 24 String nowTime=""; 25 nowTime= df.format(dt);//用DateFormat的format()方法在dt中获取并以yyyy/MM/dd HH:mm:ss格式显示 26 27 //在文件中写入数据 28 bw.write(""+this.getServletContext().getAttribute("ip")+" "+nowTime+"\r\n"); 29 //关闭文件流 30 bw.close(); 31 }catch(Exception e){ 32 e.printStackTrace(); 33 } 34 //----------------------------------------------------------- 35 try{req.setCharacterEncoding("gb2312"); 36 res.setContentType("text/html;charset=gb2312"); 37 PrintWriter pw=res.getWriter(); 38 pw.println("<html>"); 39 pw.println("<body bgcolor=#CACCF6>"); 40 pw.println("<center><img src='./imgs/imgs.jpg'/><hr>"); 41 pw.println("<h1>登陆界面</h1>"); 42 pw.println("<form action=logincl method=post>"); //跳转到logincl 43 pw.println("用户名:<input type=text name=username><br>"); 44 pw.println("密码:<input type=password name=passwd><br>"); 45 pw.println("<input type=checkbox name=keep value=2>两周内不再重新登陆<br>"); 46 pw.println("<input type=submit value=login><br>"); 47 pw.println("</form>"); 48 pw.println("</center><img src='./imgs/logo.jpg'/><hr>"); 49 pw.println("</body>"); 50 pw.println("</html>"); 51 } 52 catch(Exception e){ 53 e.printStackTrace(); 54 } 55 } 56 57 public void doPost(HttpServletRequest req,HttpServletResponse res){ 58 this.doGet(req,res); 59 } 60 }
LoginCl.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 5 import java.io.*; 6 import java.sql.*; 7 8 public class LoginCl extends HttpServlet{ 9 10 //重写init()函数 11 public void init(){ 12 try{ 13 //创建一个FileReader 14 FileReader fr=new FileReader("d:\\myCounter.txt"); 15 BufferedReader br=new BufferedReader(fr); 16 17 //读取一行 18 String numVal=br.readLine(); 19 br.close(); 20 21 //将times值放入到servletContext中 22 this.getServletContext().setAttribute("visitTimes",numVal); 23 }catch(Exception e){ 24 e.printStackTrace(); 25 } 26 } 27 28 //重写destroy函数 29 public void destroy(){ 30 try{ 31 //创建一个FileWriter,内存->磁盘,写入，输出 32 FileWriter fw=new FileWriter("d:\\myCounter.txt"); 33 BufferedWriter bw=new BufferedWriter(fw); 34 35 //在文件中写入数据 36 bw.write(""+this.getServletContext().getAttribute("visitTimes")); 37 //关闭文件流 38 bw.close(); 39 }catch(Exception e){ 40 e.printStackTrace(); 41 } 42 } 43 public void doGet(HttpServletRequest req,HttpServletResponse res){ 44 45 Connection conn=null; 46 Statement stmt=null; 47 ResultSet rs=null; 48 UserBeanCl ubc=null; 49 // String sql = "select username,passwd from users where username = ? and passwd = ?"; 50 String sql = "select passwd from users where username = ? limit 1"; 51 try{//req.setCharacterEncoding("gb2312"); 52 String user=req.getParameter("username"); 53 String password=req.getParameter("passwd"); 54 55 //调用UserBeanCl 56 ubc=new UserBeanCl(); 57 if(ubc.checkUser(user,password)) 58 { 59 HttpSession hs=req.getSession(true); 60 hs.setMaxInactiveInterval(60); 61 hs.setAttribute("name",user); 62 hs.setAttribute("pass",password); 63 64 String keep=req.getParameter("keep"); 65 if(keep!=null){ 66 67 Cookie name=new Cookie("myname",user); 68 Cookie pass=new Cookie("mypass",password); 69 name.setMaxAge(14*24*3600); 70 pass.setMaxAge(14*24*3600); 71 72 res.addCookie(name); 73 res.addCookie(pass); 74 } 75 76 //将servletContext中的visitTimes所对应的值+1 77 String times=this.getServletContext().getAttribute("visitTimes").toString(); 78 //对times的值++然后写回到servletContext 79 this.getServletContext().setAttribute("visitTimes",(Integer.parseInt(times)+1)+""); 80 81 res.sendRedirect("main"); 82 //res.sendRedirect("welcome?&uname="+user+"&upass="+password); 83 } 84 else{ 85 res.sendRedirect("login"); //url 86 } 87 88 } 89 catch(Exception e){ 90 e.printStackTrace(); 91 }finally{ 92 ubc.close(); 93 } 94 } 95 96 public void doPost(HttpServletRequest req,HttpServletResponse res){ 97 this.doGet(req,res); 98 } 99 }
MainFrame.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 5 import java.io.*; 6 7 public class MainFrame extends HttpServlet{ 8 public void doGet(HttpServletRequest req,HttpServletResponse res){ 9 try{req.setCharacterEncoding("gb2312"); 10 res.setContentType("text/html;charset=gb2312"); 11 PrintWriter pw=res.getWriter(); 12 pw.println("<html>"); 13 pw.println("<body bgcolor=#CACCF6>"); 14 pw.println("<center><img src='./imgs/imgs.jpg'/><hr>"); 15 pw.println("<h1>主界面</h1>"); 16 pw.println("<a href=welcome>管理用户</a>"); 17 pw.println("<a href=adduser>添加用户</a>"); 18 pw.println("<a href=check>查询用户</a>"); 19 pw.println("<a href=login>安全退出</a>"); 20 pw.println("</center><img src='./imgs/logo.jpg'/><hr>"); 21 pw.println("</body>"); 22 pw.println("</html>"); 23 } 24 catch(Exception e){ 25 e.printStackTrace(); 26 } 27 } 28 29 public void doPost(HttpServletRequest req,HttpServletResponse res){ 30 this.doGet(req,res); 31 } 32 }
Welcome.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 5 import java.io.*; 6 import java.sql.*; 7 import java.util.ArrayList; 8 9 public class Welcome extends HttpServlet{ 10 public void doGet(HttpServletRequest req,HttpServletResponse res){ 11 Connection conn=null; 12 Statement stmt=null; 13 ResultSet rs=null; 14 String u=null; 15 String p=null; 16 17 res.setContentType("text/html;charset=gb2312"); 18 HttpSession hs=req.getSession(); 19 String val=(String)hs.getAttribute("pass"); 20 21 Cookie []allCookies=req.getCookies(); 22 if(val==null){ 23 try{ 24 for(int i=0;i<allCookies.length;i++){ 25 26 if(allCookies[i].getName().equals("myname")) 27 u=allCookies[i].getValue(); 28 29 else if(allCookies[i].getName().equals("mypass")) 30 p=allCookies[i].getValue(); 31 } 32 if(u!=null&&p!=null){ 33 // hs.setAttribute("pass",p); 34 // res.sendRedirect("welcome?&uname="+u+"&upass="+p); 35 res.sendRedirect("logincl?username="+u+"&passwd="+p); 36 return ; 37 } 38 39 res.sendRedirect("login"); 40 return ; 41 }catch(Exception e){ 42 e.printStackTrace(); 43 } 44 45 } 46 47 u=req.getParameter("uname"); 48 p=req.getParameter("upass"); 49 50 try{//req.setCharacterEncoding("gb2312"); 51 52 int pageSize=5;//每一页显示记录数 53 int pageNow=1; //当前页 54 55 //动态接收pageNow 56 String sPageNow=req.getParameter("pageNow"); 57 if(sPageNow!=null){ 58 pageNow=Integer.parseInt(sPageNow); 59 } 60 61 //调用UserBeanCl 62 UserBeanCl ubc=new UserBeanCl(); 63 ArrayList al=ubc.getResultByPage(pageNow,pageSize); 64 65 PrintWriter pw=res.getWriter(); 66 67 pw.println("<body><center>"); 68 pw.println("<body bgcolor=#CACCF6>"); 69 pw.println("<img src='./imgs/imgs.jpg'/>"); 70 pw.println("<h1>管理用户</h1>"); 71 pw.println("<table border=1>");//带边框的表格 72 pw.println("<tr><th>id</th><th>name</th><th>password</th><th>email</th><th>grade</th><th>修改用户</th><th>删除用户</th></tr>");//表头 73 for(int i=0;i<al.size();i++){ 74 UserBean ub=(UserBean)al.get(i); 75 pw.println("<tr>"); 76 pw.println("<td>"+ub.getUserId()+"</td>"); 77 pw.println("<td>"+ub.getUserName()+"</td>"); 78 pw.println("<td>"+ub.getPasswd()+"</td>"); 79 pw.println("<td>"+ub.getEmail()+"</td>"); 80 pw.println("<td>"+ub.getGrade()+"</td>"); 81 pw.println("<td><a href=update?uId="+ub.getUserId()+"&uName="+ub.getUserName()+"&uPass="+ub.getPasswd()+"&uMail="+ub.getEmail()+"&uGrade="+ub.getGrade()+">修改用户</a></td>"); 82 pw.println("<td><a href=delete?userid="+ub.getUserId()+" onclick=\"return window.confirm('你确认要删除该用户吗？')\">删除用户</a></td>"); 83 pw.println("</tr>"); 84 } 85 pw.println("</table>"); 86 // res.setContentType("text/html;charset=gb2312"); 87 int pageCount=ubc.getPageCount(); 88 if(pageNow!=1) 89 pw.println("<a href=welcome?pageNow="+(pageNow-1)+"&uname="+u+"&upass="+p+">"+"last"+"</a>"); 90 91 for(int i=pageNow;i<=pageNow+4;i++){ 92 pw.println("<a href=welcome?pageNow="+i+"&uname="+u+"&upass="+p+">"+i+"</a>"); 93 } 94 if(pageNow!=pageCount) 95 pw.println("<a href=welcome?pageNow="+(pageNow+1)+"&uname="+u+"&upass="+p+">"+"next"+"</a>"); 96 97 //跳转功能 98 pw.println("<form action=welcome method=post>"); 99 pw.println("Go to<input type=text name=pageNow>page<br>"); 100 pw.println("<input type=submit value=Go><br>"); 101 102 // pw.println("<img src='./imgs/imgs.jpg'/>"); 103 // pw.println("welcome! "+u+"&pass="+p); 104 pw.println("该网页被访问了"+this.getServletContext().getAttribute("visitTimes").toString()+"次"); 105 pw.println("你的IP："+req.getRemoteAddr()+"<br>"); 106 pw.println("你的机器名="+req.getRemoteHost()+"<br>"); 107 pw.println("</center><img src='./imgs/logo.jpg'/><hr>"); 108 pw.println("</body>"); 109 } 110 catch(Exception e){ 111 e.printStackTrace(); 112 }finally{ 113 114 } 115 } 116 public void doPost(HttpServletRequest req,HttpServletResponse res){ 117 this.doGet(req,res); 118 } 119 }
UserBeanCl.java
1 //处理users表的类,操作userbean 2 //业务逻辑 3 package com.bai; 4 import java.sql.*; 5 import java.util.ArrayList; 6 public class UserBeanCl{ 7 //业务逻辑 8 private Connection conn=null; 9 private PreparedStatement ps=null; 10 private ResultSet rs=null; 11 private int rowCount=0;//共有几条记录 12 private int pageCount=0;//共有几页 13 14 //查询用户 15 public ArrayList Check(String querytype,String username){ 16 ArrayList al=new ArrayList(); 17 try{ 18 //得到连接 19 ConnDB cd=new ConnDB(); 20 conn=cd.getConn(); 21 Statement stmt = conn.createStatement(); 22 if(querytype.equals("fuzzy")){ //模糊查询 23 //模糊查询算法 24 char arr[]=username.toCharArray(); 25 String sql="select * from users where "; 26 for(int i=0;i<username.length();i++){ 27 if(i==0) 28 sql=sql.concat("upper(username) like '%"+arr[i]+"%' "); 29 else sql=sql.concat("and upper(username) like '%"+arr[i]+"%' "); 30 } 31 System.out.println(sql); 32 rs=stmt.executeQuery(sql); 33 34 } 35 if(querytype.equals("precise")){ //精确查询 36 ps=conn.prepareStatement("select * from users where username=?"); 37 ps.setString(1,username); 38 rs=ps.executeQuery(); 39 System.out.println(ps); 40 //String sql1=("select * from users where username="); 41 //sql1=sql1.concat(username); 42 //System.out.println(sql1); 43 //rs=stmt.executeQuery(sql1); 44 } 45 while(rs.next()){ 46 //将rs中每条记录封装到userbean中 47 UserBean ub=new UserBean(); 48 ub.setUserId(rs.getInt(1)); 49 ub.setUserName(rs.getString(2)); 50 ub.setPasswd(rs.getString(3)); 51 ub.setEmail(rs.getString(4)); 52 ub.setGrade(rs.getInt(5)); 53 54 //将ub放入到ArrayList中 55 al.add(ub); 56 } 57 }catch(Exception e){ 58 e.printStackTrace(); 59 }finally{ 60 this.close(); 61 } 62 return al; 63 } 64 65 //添加用户 66 public boolean AddUser(String id,String username,String email,String passwd,String grade){ 67 try{ 68 //得到连接 69 ConnDB cd=new ConnDB(); 70 conn=cd.getConn(); 71 72 ps=conn.prepareStatement("insert into users(userId,username,passwd,email,grade) values(?,?,?,?,?)"); 73 ps.setString(1,id); 74 ps.setString(2,username); 75 ps.setString(3,email); 76 ps.setString(4,passwd); 77 ps.setString(5,grade); 78 79 int num=ps.executeUpdate(); 80 if(num==1){ 81 return true; 82 } 83 84 }catch(Exception e){ 85 e.printStackTrace(); 86 }finally{ 87 this.close(); 88 } 89 return false; 90 } 91 92 //修改用户 93 public boolean UpdateUser(String id,String email,String passwd,String grade){ 94 try{ 95 //得到连接 96 ConnDB cd=new ConnDB(); 97 conn=cd.getConn(); 98 99 ps=conn.prepareStatement("update users set email=?,passwd=?,grade=? where userId=?"); 100 ps.setString(1,email); 101 ps.setString(2,passwd); 102 ps.setString(3,grade); 103 ps.setString(4,id); 104 int num=ps.executeUpdate(); 105 if(num==1){ 106 return true; 107 } 108 109 }catch(Exception e){ 110 e.printStackTrace(); 111 }finally{ 112 this.close(); 113 } 114 return false; 115 } 116 117 //删除用户 118 public boolean deleteUser(String id){ 119 try{ 120 //得到连接 121 ConnDB cd=new ConnDB(); 122 conn=cd.getConn(); 123 124 ps=conn.prepareStatement("delete from users where userId=?"); 125 ps.setString(1,id); 126 int num=ps.executeUpdate(); 127 if(num==1){ 128 return true; 129 } 130 131 }catch(Exception e){ 132 e.printStackTrace(); 133 }finally{ 134 this.close(); 135 } 136 return false; 137 } 138 139 //返回pageCount 140 public int getPageCount(){ 141 return this.pageCount; 142 } 143 //分页显示 144 public ArrayList getResultByPage(int pageNow,int pageSize){ 145 146 ArrayList al=new ArrayList(); 147 try{ 148 149 ConnDB cd=new ConnDB(); 150 conn=cd.getConn(); 151 ps=conn.prepareStatement("select count(*) from users"); 152 rs=ps.executeQuery(); 153 //得到行数 154 if(rs.next()){ 155 rowCount = rs.getInt(1); 156 } 157 //计算页数 158 if(rowCount%pageSize==0){ 159 pageCount=rowCount/pageSize; 160 }else{ 161 pageCount=rowCount/pageSize+1; 162 } 163 String sql="select * from users where userId not in(select * from(select userId from users limit ?)a) limit ?"; 164 PreparedStatement pstmt = conn.prepareStatement(sql); 165 pstmt.setInt(2,pageSize); 166 pstmt.setInt(1,pageSize*(pageNow-1)); 167 rs=pstmt.executeQuery(); 168 169 while(rs.next()){ 170 //将rs中每条记录封装到userbean中 171 UserBean ub=new UserBean(); 172 ub.setUserId(rs.getInt(1)); 173 ub.setUserName(rs.getString(2)); 174 ub.setPasswd(rs.getString(3)); 175 ub.setEmail(rs.getString(4)); 176 ub.setGrade(rs.getInt(5)); 177 178 //奖ub放入到ArrayList中 179 al.add(ub); 180 } 181 }catch(Exception e){ 182 e.printStackTrace(); 183 }finally{ 184 this.close(); 185 } 186 return al; 187 } 188 189 //验证用户 190 public boolean checkUser(String u,String p){ 191 boolean b=false; 192 try{ 193 //得到连接 194 ConnDB cd=new ConnDB(); 195 conn=cd.getConn(); 196 197 ps=conn.prepareStatement("select passwd from users where username = ? limit 1"); 198 ps.setString(1,u); 199 rs=ps.executeQuery(); 200 201 if(rs.next()){ 202 String dbPasswd=rs.getString(1); 203 if(dbPasswd.equals(p)) { 204 b=true; 205 } 206 } 207 }catch(Exception e){ 208 e.printStackTrace(); 209 }finally{ 210 this.close(); 211 } 212 return b; 213 } 214 215 //关闭数据库连接 216 public void close(){ 217 try{ 218 if(rs!=null){ 219 rs.close(); 220 rs=null; 221 } 222 if(ps!=null){ 223 ps.close(); 224 ps=null; 225 } 226 if(conn!=null){ 227 conn.close(); 228 conn=null; 229 } 230 }catch(Exception e){ 231 e.printStackTrace(); 232 } 233 } 234 }
ConnDB.java //获取数据库连接
1 //g从数据库得到连接 2 3 package com.bai; 4 import java.sql.*; 5 6 public class ConnDB{ 7 private Connection conn=null; 8 public Connection getConn(){ 9 try{ 10 //加载驱动 11 Class.forName("com.mysql.jdbc.Driver"); 12 //得到连接 13 conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/sqdb","root","root"); 14 }catch(Exception e){ 15 e.printStackTrace(); 16 } 17 return conn; 18 } 19 }
UserBean.java
1 package com.bai; 2 3 public class UserBean{ 4 private int userId; 5 private String userName; 6 private String passwd; 7 private String email; 8 private int grade; 9 10 public void setUserId(int userId){ 11 this.userId=userId; 12 } 13 public int getUserId(){ 14 return (this.userId); 15 } 16 17 18 public void setEmail(String email) { 19 this.email = email; 20 } 21 22 public String getEmail() { 23 return (this.email); 24 } 25 26 27 public void setUserName(String userName) { 28 this.userName = userName; 29 } 30 31 public void setPasswd(String passwd) { 32 this.passwd = passwd; 33 } 34 35 public void setGrade(int grade) { 36 this.grade = grade; 37 } 38 39 public String getUserName() { 40 return (this.userName); 41 } 42 43 public String getPasswd() { 44 return (this.passwd); 45 } 46 47 public int getGrade() { 48 return (this.grade); 49 } 50 }
Update.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 5 import java.io.*; 6 7 public class Update extends HttpServlet{ 8 9 public void doGet(HttpServletRequest req,HttpServletResponse res){ 10 11 12 try{req.setCharacterEncoding("gb2312"); 13 res.setContentType("text/html;charset=gb2312"); 14 PrintWriter pw=res.getWriter(); 15 pw.println("<html>"); 16 pw.println("<body bgcolor=#CACCF6>"); 17 pw.println("<center><img src='./imgs/imgs.jpg'/><hr>"); 18 19 pw.println("<h1>修改用户界面</h1>"); 20 pw.println("<form action=updatecl>"); 21 pw.println("<table border=1>"); 22 23 pw.println("<tr><td>id</td><td><input readonly name=userid type=text value="+req.getParameter("uId")+"></td></tr>"); 24 pw.println("<tr><td>name</td><td><input readonly type=text value="+req.getParameter("uName")+"></td></tr>"); 25 pw.println("<tr><td>passwd</td><td><input type=text name=newPass value="+req.getParameter("uPass")+"></td></tr>"); 26 pw.println("<tr><td>email</td><td><input type=text name=newEmail value="+req.getParameter("uMail")+"></td></tr>"); 27 pw.println("<tr><td>grade</td><td><input type=text name=newGrade value="+req.getParameter("uGrade")+"></td></tr>"); 28 pw.println("<tr><td colspan=2><input type=submit value=修改用户></td></tr>"); 29 pw.println("</table></form>"); 30 31 pw.println("</center><img src='./imgs/logo.jpg'/><hr>"); 32 pw.println("</body>"); 33 pw.println("</html>"); 34 } 35 catch(Exception e){ 36 e.printStackTrace(); 37 } 38 } 39 40 public void doPost(HttpServletRequest req,HttpServletResponse res){ 41 this.doGet(req,res); 42 } 43 }
UpdateCl.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 5 import java.io.*; 6 7 public class UpdateCl extends HttpServlet{ 8 public void doGet(HttpServletRequest req,HttpServletResponse res){ 9 try{ 10 res.setContentType("text/html;charset=gbk"); 11 12 UserBeanCl ubc=new UserBeanCl(); 13 14 if(ubc.UpdateUser(req.getParameter("userid"),req.getParameter("newEmail"),req.getParameter("newPass"),req.getParameter("newGrade"))){ 15 //删除成功 16 res.sendRedirect("ok"); 17 }else{ 18 //删除失败 19 res.sendRedirect("err"); 20 } 21 } 22 catch(Exception e){ 23 e.printStackTrace(); 24 } 25 } 26 27 public void doPost(HttpServletRequest req,HttpServletResponse res){ 28 this.doGet(req,res); 29 } 30 }
AddUser.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 5 import java.io.*; 6 7 public class AddUser extends HttpServlet{ 8 9 public void doGet(HttpServletRequest req,HttpServletResponse res){ 10 11 12 try{req.setCharacterEncoding("gb2312"); 13 res.setContentType("text/html;charset=gb2312"); 14 PrintWriter pw=res.getWriter(); 15 pw.println("<html>"); 16 pw.println("<body bgcolor=#CACCF6>"); 17 pw.println("<center><img src='./imgs/imgs.jpg'/><hr>"); 18 19 pw.println("<h1>添加用户界面</h1>"); 20 pw.println("<form action=addusercl method=post>"); 21 22 pw.println("用户id:<input type=text name=userid><br>"); 23 pw.println("用户名:<input type=text name=username><br>"); 24 pw.println("密 码:<input type=password name=passwd><br>"); 25 pw.println("邮 箱:<input type=text name=email><br>"); 26 pw.println("等 级:<input type=text name=grade><br>"); 27 28 pw.println("<input type=submit value=添加><br>"); 29 pw.println("</form>"); 30 31 pw.println("</center><img src='./imgs/logo.jpg'/><hr>"); 32 pw.println("</body>"); 33 pw.println("</html>"); 34 } 35 catch(Exception e){ 36 e.printStackTrace(); 37 } 38 } 39 40 public void doPost(HttpServletRequest req,HttpServletResponse res){ 41 this.doGet(req,res); 42 } 43 }
AddUserCl.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 5 import java.io.*; 6 7 public class AddUserCl extends HttpServlet{ 8 public void doGet(HttpServletRequest req,HttpServletResponse res){ 9 try{ 10 res.setContentType("text/html;charset=gbk"); 11 12 UserBeanCl ubc=new UserBeanCl(); 13 14 if(ubc.AddUser(req.getParameter("userid"),req.getParameter("username"),req.getParameter("email"),req.getParameter("passwd"),req.getParameter("grade"))){ 15 //删除成功 16 res.sendRedirect("ok"); 17 }else{ 18 //删除失败 19 res.sendRedirect("err"); 20 } 21 } 22 catch(Exception e){ 23 e.printStackTrace(); 24 } 25 } 26 27 public void doPost(HttpServletRequest req,HttpServletResponse res){ 28 this.doGet(req,res); 29 } 30 }
DeleteUser.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 5 import java.io.*; 6 7 public class DeleteUser extends HttpServlet{ 8 public void doGet(HttpServletRequest req,HttpServletResponse res){ 9 try{ 10 res.setContentType("text/html;charset=gbk"); 11 12 //调用userBean的删除用户的方法，完成删除 13 UserBeanCl ubc=new UserBeanCl(); 14 //接收从welcome.java中传递的id 15 String id=req.getParameter("userid"); 16 System.out.println("id="+id); 17 if(ubc.deleteUser(id)){ 18 //删除成功 19 res.sendRedirect("ok"); 20 }else{ 21 //删除失败 22 res.sendRedirect("err"); 23 } 24 } 25 catch(Exception e){ 26 e.printStackTrace(); 27 } 28 } 29 30 public void doPost(HttpServletRequest req,HttpServletResponse res){ 31 this.doGet(req,res); 32 } 33 }
DeleteError.java
1 //删除失败 2 3 package com.bai; 4 5 import javax.servlet.http.*; 6 7 import java.io.*; 8 9 public class DeleteError extends HttpServlet{ 10 public void doGet(HttpServletRequest req,HttpServletResponse res){ 11 try{ 12 res.setContentType("text/html;charset=gbk"); 13 PrintWriter pw=res.getWriter(); 14 pw.println("<html>"); 15 pw.println("<body bgcolor=#CACCF6>"); 16 pw.println("<center><img src='./imgs/imgs.jpg'/><hr>"); 17 18 pw.println("<h1>操作失败!</h1>"); 19 pw.println("</center><img src='./imgs/logo.jpg'/><hr>"); 20 pw.println("</body>"); 21 pw.println("</html>"); 22 } 23 catch(Exception e){ 24 e.printStackTrace(); 25 } 26 } 27 28 public void doPost(HttpServletRequest req,HttpServletResponse res){ 29 this.doGet(req,res); 30 } 31 }
Ok.java
1 //删除成功界面 2 package com.bai; 3 4 import javax.servlet.http.*; 5 6 import java.io.*; 7 8 public class Ok extends HttpServlet{ 9 public void doGet(HttpServletRequest req,HttpServletResponse res){ 10 try{ 11 res.setContentType("text/html;charset=gbk"); 12 PrintWriter pw=res.getWriter(); 13 pw.println("<html>"); 14 pw.println("<body bgcolor=#CACCF6>"); 15 pw.println("<center><img src='./imgs/imgs.jpg'/><hr>"); 16 17 pw.println("<h1>操作成功!</h1>"); 18 pw.println("<a href=main>返回主界面</a> <a href=welcome>继续删除用户</a>"); 19 pw.println("</center><img src='./imgs/logo.jpg'/><hr>"); 20 pw.println("</body>"); 21 pw.println("</html>"); 22 } 23 catch(Exception e){ 24 e.printStackTrace(); 25 } 26 } 27 28 public void doPost(HttpServletRequest req,HttpServletResponse res){ 29 this.doGet(req,res); 30 } 31 }
新增的查询功能
CheckUser.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 5 import java.io.*; 6 7 public class CheckUser extends HttpServlet{ 8 9 public void doGet(HttpServletRequest req,HttpServletResponse res){ 10 11 12 try{req.setCharacterEncoding("gb2312"); 13 res.setContentType("text/html;charset=gb2312"); 14 PrintWriter pw=res.getWriter(); 15 pw.println("<html>"); 16 pw.println("<body bgcolor=#CACCF6>"); 17 pw.println("<center><img src='./imgs/imgs.jpg'/><hr>"); 18 pw.println("<h1>查询用户</h1>"); 19 20 pw.println("<form action=checkop method=post>"); 21 pw.println("请输入用户名:<input type=text name=username>"); 22 pw.println("<input type=submit value=查询><br>"); 23 pw.println("<input type=radio checked=checked name=querytype value=fuzzy>模糊查询<br>"); 24 pw.println("<input type=radio name=querytype value=precise>精确查询<br>"); 25 pw.println("</form>"); 26 27 pw.println("</center><img src='./imgs/logo.jpg'/><hr>"); 28 pw.println("</body>"); 29 pw.println("</html>"); 30 } 31 catch(Exception e){ 32 e.printStackTrace(); 33 } 34 } 35 36 public void doPost(HttpServletRequest req,HttpServletResponse res){ 37 this.doGet(req,res); 38 } 39 }
CheckUserOperation.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 import java.util.ArrayList; 5 import java.io.*; 6 7 public class CheckUserOperation extends HttpServlet{ 8 public void doGet(HttpServletRequest req,HttpServletResponse res){ 9 try{ 10 res.setContentType("text/html;charset=gbk"); 11 UserBeanCl ubc=new UserBeanCl(); 12 13 HttpSession hs=req.getSession(true); 14 15 ArrayList al=new ArrayList(); 16 al=null; 17 al=ubc.Check(req.getParameter("querytype"),req.getParameter("username")); 18 if(al.size()!=0){ 19 //查询到结果 20 res.sendRedirect("checkresult?state="+"true"); 21 hs.setAttribute("result",al); 22 }else{ 23 //没查询到结果 24 System.out.println("no result"); 25 26 res.sendRedirect("checkresult?state="+"false"); 27 } 28 } 29 catch(Exception e){ 30 e.printStackTrace(); 31 } 32 } 33 34 public void doPost(HttpServletRequest req,HttpServletResponse res){ 35 this.doGet(req,res); 36 } 37 }
CheckResult.java
1 package com.bai; 2 3 import javax.servlet.http.*; 4 import java.util.ArrayList; 5 import java.io.*; 6 7 public class CheckResult extends HttpServlet{ 8 9 public void doGet(HttpServletRequest req,HttpServletResponse res){ 10 11 ArrayList al=new ArrayList(); 12 HttpSession hs=req.getSession(); 13 14 try{req.setCharacterEncoding("gb2312"); 15 res.setContentType("text/html;charset=gb2312"); 16 PrintWriter pw=res.getWriter(); 17 pw.println("<html>"); 18 pw.println("<body bgcolor=#CACCF6>"); 19 pw.println("<center><img src='./imgs/imgs.jpg'/><hr>"); 20 pw.println("<h1>查询用户</h1>"); 21 22 pw.println("<form action=checkop method=post>"); 23 pw.println("请输入用户名:<input type=text name=username>"); 24 pw.println("<input type=submit value=查询><br>"); 25 pw.println("<input type=radio checked=checked name=querytype value=fuzzy>模糊查询<br>"); 26 pw.println("<input type=radio name=querytype value=precise>精确查询<br>"); 27 pw.println("</form>"); 28 29 //如果查询到，则列出结果 30 if(req.getParameter("state").equals("true")){ 31 al=(ArrayList)hs.getAttribute("result"); 32 pw.println("<table border=1>");//带边框的表格 33 pw.println("<tr><th>id</th><th>name</th><th>password</th><th>email</th><th>grade</th></tr>");//表头 34 for(int i=0;i<al.size();i++){ 35 UserBean ub=(UserBean)al.get(i); 36 pw.println("<tr>"); 37 pw.println("<td>"+ub.getUserId()+"</td>"); 38 pw.println("<td>"+ub.getUserName()+"</td>"); 39 pw.println("<td>"+ub.getPasswd()+"</td>"); 40 pw.println("<td>"+ub.getEmail()+"</td>"); 41 pw.println("<td>"+ub.getGrade()+"</td>"); 42 pw.println("</tr>"); 43 } 44 pw.println("</table>"); 45 }else{ 46 pw.println("找不到此用户"); 47 } 48 pw.println("</center><img src='./imgs/logo.jpg'/><hr>"); 49 pw.println("</body>"); 50 pw.println("</html>"); 51 } 52 catch(Exception e){ 53 e.printStackTrace(); 54 } 55 } 56 57 public void doPost(HttpServletRequest req,HttpServletResponse res){ 58 this.doGet(req,res); 59 } 60 }