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在jsp中用bean和servlet聯合實現用戶注冊、登錄

作者：imagebear
版權：imagebear

本例需要的軟件和運行環境：
1、Windows2000 Server操作系統
2、jdk1.4
3、JCreator2.5（java源碼編輯調試器，吐血推薦?。?BR>4、Macromedia JRun MX
5、Macromedia Dreamweaver MX（非必需）
6、MySQL數據庫（最好安裝MySQL Control Center）

一、數據庫設計
用MySQL Control Center打開MySQL數據庫，新建數據庫shopping，在其下新建表tbl_user，其中各字段設置如下：

二、編寫連接數據庫bean：DBConn.java

//DBConn.java

//include required classes
import java.sql.*;

//==========================================
// Define Class DBConn
//==========================================
public class DBConn
{
 public String sql_driver = "org.gjt.mm.mysql.Driver";
 public String sql_url = "jdbc:mysql://localhost:3306";
 public String sql_DBName = "shopping";
 public String user = "sa";
 public String pwd = ";

 Connection conn = null;
 Statement stmt = null;
 ResultSet rs = null;

 public boolean setDriver(String drv)
 {
  this.sql_driver = drv;
  return true;
 }

 public String getDriver()
 {
  return this.sql_driver;
 }

 public boolean setUrl(String url)
 {
  this.sql_url = url;
  return true;
 }

 public boolean setDBName(String dbname)
 {
  this.sql_DBName = dbname;
  return true;
 }

 public String getDBName()
 {
  return this.sql_DBName;
 }

 public boolean setUser(String user)
 {
  this.user = user;
  return true;
 }

 public String getUser()
 {
  return this.user;
 }

 public boolean setPwd(String pwd)
 {
  this.pwd = pwd;
  return true;
 }

 public String getPwd()
 {
  return this.pwd;
 }

 public DBConn()
 {
  try{
   Class.forName(sql_driver);//加載數據庫驅動程序
   this.conn = DriverManager.getConnection(sql_url + "/" + sql_DBName + "?user=" + user + "password=" + pwd + "useUnicode=truecharacterEncoding=gb2312");
   this.stmt = this.conn.createStatement();
  }catch(Exception e){
   System.out.println(e.toString());
  }
 }

                //執行查詢操作
 public ResultSet executeQuery(String strSql)
 {
  try{
   this.rs = stmt.executeQuery(strSql);
   return this.rs;
  }catch(SQLException e){
   System.out.println(e.toString());
   return null;
  }catch(NullPointerException e){
   System.out.println(e.toString());
   return null;
  }
 }

                //執行數據的插入、刪除、修改操作
 public boolean execute(String strSql)
 {
  try{
   if(this.stmt.executeUpdate(strSql) == 0)
    return false;
   else
    return true;
  }catch(SQLException e){
   System.out.println(e.toString());
   return false;
  }catch(NullPointerException e){
   System.out.println(e.toString());
   return false;
  }
 }

                //結果集指針跳轉到某一行
 public boolean rs_absolute(int row)
 {
  try{
   this.rs.absolute(row);
   return true;
  }catch(SQLException e){
   System.out.println(e.toString());
   return false;
  }
 }

 public void rs_afterLast()
 {
  try{
   this.rs.afterLast();
  }catch(SQLException e){
   System.out.println(e.toString());
  }
 }

 public void rs_beforeFirst()
 {
  try{
   this.rs.beforeFirst();
  }catch(SQLException e){
   System.out.print(e.toString());
  }
 }

 public void rs_close()
 {
  try{
   this.rs.close();
  }catch(SQLException e){
   System.out.print(e.toString());
  }
 }

 public void rs_deleteRow()
 {
  try{
   this.rs.deleteRow();
  }catch(SQLException e){
   System.out.print(e.toString());
  }
 }

 public boolean rs_first()
 {
  try{
   this.rs.first();
   return true;
  }catch(SQLException e){
   System.out.print(e.toString());
   return false;
  }
 }

 public String rs_getString(String column)
 {
  try{
   return this.rs.getString(column);
  }catch(SQLException e){
   System.out.println(e.toString());
   return null;
  }
 }

                //此方法用于獲取大段文本，
                //將其中的回車換行替換為br>
                //輸出到html頁面
 public String rs_getHtmlString(String column)
 {
  try{
   String str1 = this.rs.getString(column);
   String str2 = "\r\n";
   String str3 = "br>";
   return this.replaceAll(str1,str2,str3);
  }catch(SQLException e){
   System.out.println(e.toString());
   return null;
  }
 }

                //把str1字符串中的str2字符串替換為str3字符串
 private static String replaceAll(String str1,String str2,String str3)
 {
  StringBuffer strBuf = new StringBuffer(str1);
     int index=0;
  while(str1.indexOf(str2,index)!=-1)
  {
   index=str1.indexOf(str2,index);
   strBuf.replace(str1.indexOf(str2,index),str1.indexOf(str2,index)+str2.length(),str3);
   index=index+str3.length();

    str1=strBuf.toString();
  }
  return strBuf.toString();
 }

 public int rs_getInt(String column)
 {
  try{
   return this.rs.getInt(column);
  }catch(SQLException e){
   System.out.println(e.toString());
   return -1;
  }
 }

 public int rs_getInt(int column)
 {
  try{
   return this.rs.getInt(column);
  }catch(SQLException e){
   System.out.println(e.toString());
   return -1;
  }
 }

 public boolean rs_next()
 {
  try{
   return this.rs.next();
  }catch(SQLException e){
   System.out.println(e.toString());
   return false;
  }
 }

                //判斷結果集中是否有數據
 public boolean hasData()
 {
  try{
   boolean has_Data = this.rs.first();  
   this.rs.beforeFirst();
   return has_Data;
  }catch(SQLException e){
   System.out.println(e.toString());
   return false;
  }
 }

 public boolean rs_last()
 {
  try{
   return this.rs.last();
  }catch(SQLException e){
   System.out.println(e.toString());
   return false;
  }
 }

 public boolean rs_previous()
 {
  try{
   return this.rs.previous();
  }catch(Exception e){
   System.out.println(e.toString());
   return false;
  }
 }

                //main方法，調試用
 public static void main(String args[])
 {
  try{
   DBConn myconn = new DBConn();
   //myconn.setDBName("shopping");
   //myconn.DBConn();
   //myconn.execute("Insert Into tbl_test(id,name) values('10','shandaer')");
   //myconn.execute("Update tbl_test set name='yyyyyyyyyyyy' where id=10");
   //myconn.execute("Delete from tbl_test where id=1");
   ResultSet rs = myconn.executeQuery("select * from tbl_user order by id desc limit 1");
   //boolean hasData = myconn.hasData();
   //System.out.println("has data:" + hasData);
   //rs.first();
   while (myconn.rs.next()) 
   {
    int id = myconn.rs_getInt("id") + 1;
    System.out.print(id);
    System.out.println(myconn.rs_getInt("id") + myconn.rs_getString("name"));

    //System.out.println('\n' + myconn.rs_getHtmlString("name"));
    //System.out.println(myconn.rs.getString("name") + myconn.rs_getInt(1));
   }
  }catch(Exception e){
   System.err.println(e.toString());
  }
 }

}

聲明：因為使用的是MySQL數據庫，所以需要MySQL數據庫的驅動
下載后請將org包放至DBConn.java所在目錄下
以確保該bean能正常運行

三、編寫用戶注冊的bean：reg.java

//reg.java

//import required classes
import java.sql.*;

public class reg
{
 public int newID = 0;
 public boolean result = false;
 public boolean reg(String username,String password,String confirm,String email)
 {
  try{
   if(!this.checkUser(username))
    return false;
   if(!this.checkPwd(password))
    return false;
   if(!this.verifyPwd(password,confirm))
    return false;
   if(!this.checkEmail(email))
    return false;
   if(!this.userNotExit(username))
    return false;
   this.getNewID(); 
   this.result = this.register(username,password,confirm,email);
   return this.result;
  }catch(Exception e){
   System.out.println(e.toString());
   return false;
  }
 }//End boolean reg

 public boolean checkUser(String user)
 {
  try{  
   if(user.indexOf("'")!=-1)
   {
    System.out.println("姓名中含有非法字符！");
    return false;
   }else
    return true;
  }catch(Exception e){
   System.out.println(e.toString());
   return false;
   }
 }

 public boolean checkPwd(String pwd)
 {
  try{
   if(pwd.indexOf("'")!=-1)
   {
    System.out.println("密碼中含有非法字符！");
    return false;
   }else
    return true;
  }catch(Exception e){
   System.out.println(e.toString());
   return false;
  }
 }

 public boolean verifyPwd(String pwd,String confirm)
 {
  try{
   if(!pwd.equals(confirm))
   {
    System.out.println("兩次輸入的密碼不一致！");
    return false;
   }else
    return true;
  }catch(Exception e){
   System.out.println(e.toString());
   return false;
  }
 }

 public boolean checkEmail(String email)
 {
  try{
   if(email.indexOf("'")!=-1)
   {
    System.out.println("E-mail中含有非法字符！");
    return false;
   }else
    return true;
  }catch(Exception e){
   System.out.println(e.toString());
   return false;
  }
 }

 public boolean userNotExit(String user)
 {
  try{
   DBConn userDBConn = new DBConn();
   userDBConn.executeQuery("select * from tbl_user where name='" + user + "'");
   if(userDBConn.rs_next())
   {
    System.out.println("用戶名已存在，請選擇其它的用戶名！");
    return false;
   }else
    return true;
  }catch(Exception e){
   System.out.println(e.toString());
   return false;
   }
 }

 public int getNewID()
 {
  try{
   DBConn newIDDBConn = new DBConn();
   newIDDBConn.executeQuery("select * from tbl_user order by id desc limit 1");
   if(newIDDBConn.rs_next())
   {
    this.newID = newIDDBConn.rs_getInt("id") + 1;
    System.out.println(this.newID);
   }else{
    this.newID = 1;
   }
   return this.newID;
  }catch(Exception e){
   System.out.println(e.toString());
   return -1;
   }   
 }

 public int getID()
 {
  return this.newID;
 }

 public boolean register(String username,String password,String confirm,String email)
 {
  try{
   DBConn regDBConn = new DBConn();
   String strSQL = "insert into tbl_user(id,name,pwd,email) values('" + this.newID +"','" + username + "','" + password + "','" + email + "')";
   regDBConn.execute(strSQL);
   return true;
  }catch(Exception e){
   System.out.println(e.toString());
   return false;
   }
 }

 public static void main(String args[])
 {
  try{

   reg newreg = new reg();  

   System.out.println(newreg.reg("sssssssss","ssssss","ssssss","imagebear@163.com"));

   DBConn myconn = new DBConn();
   myconn.executeQuery("select * from tbl_user");
   while(myconn.rs_next())
   {
    System.out.println(myconn.rs_getInt("id") + "    " + myconn.rs_getString("name") + "    " + myconn.rs_getString("pwd") + "    " + myconn.rs_getString("email"));
   }
   System.out.println(newreg.getID());
  }catch(Exception e){
   System.err.println(e.toString());
  }
 }
};

說明：
1、該bean文件應和上文所述DBConn.class文件放于同一目錄下
2、本例主要研究注冊的過程，其中的Email檢測等方法并不完善，若要應用請自行設計方法

四、編寫用戶登陸的Servlet：login.java

//login.java

//import required classes
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;

//class login
public class login extends HttpServlet
{
 public void doGet(HttpServletRequest req,HttpServletResponse res)
 throws IOException,ServletException
 {
  String username = req.getParameter("username");
  String password = req.getParameter("password");
  if(this.checklogin(username,password))
  {
   Cookie mylogin = new Cookie("username",username);
   mylogin.setVersion(1);
   mylogin.setPath("/");
   mylogin.setComment("Your login username");
   res.addCookie(mylogin);
  }
  //Cookie[] myCookies = req.getCookies();
  //String nameValue = this.getCookieValue(myCookies,"username","not found");
  //PrintWriter out = res.getWriter();
  //out.println("username" + ":" + nameValue);
  //out.println("Test Cookie Success!");
  res.sendRedirect("/index.jsp");
 }

 public void doPost(HttpServletRequest req,HttpServletResponse res)
 throws IOException,ServletException
 {
  doGet(req,res);
 }

 public static String getCookieValue(Cookie[] cookies,String cookieName,String defaultValue)
 {
  for(int i=0;icookies.length;i++) {
  Cookie cookie = cookies[i];
  if (cookieName.equals(cookie.getName()))
  return(cookie.getValue());
 }
  return(defaultValue);
 }

 public boolean checklogin(String username,String password)
 {
  try{
   DBConn loginConn = new DBConn();
   loginConn.executeQuery("select * from tbl_user where name='" + username + "'");
   if(loginConn.rs_next())
   {
    System.out.println("Connection created!");
    if(loginConn.rs_getString("pwd").trim().equals(password))
    {
     System.out.println(loginConn.rs_getString("name"));
     return true;
    }
    else
    {
     return false;
    }
   }
   System.out.println("Test Login Success!");
   return false;
  }catch(Exception e){
   System.out.println(e.toString());
   return false;
   }
 }

 public static void main(String args[])
 {
  login mylogin = new login();
  System.out.println(mylogin.checklogin("shandong","shandong"));
 }

}

說明：
1、默認的jdk1.4中并沒有servlet包，請至sun公司網頁下載servlet.jar，放至jdk目錄下的jre\lib\目錄下，并在JCreator中設置jdk處添加servlet.jar包 

2、本Servlet用于檢驗用戶名和密碼，若正確則將用戶名寫入Cookie，完成后將當前頁重定向到index.jsp頁

五、編寫檢測用戶是否已經登陸的bean：checkLogin.java

//checkLogin.java

//import required classes
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;

//class checkLogin
public class checkLogin
{
 public String username = ";

 public boolean check(HttpServletRequest req,HttpServletResponse res)
 throws IOException,ServletException
 {
  String cookieName = "username";
  Cookie[] myCookies = req.getCookies();
  this.username = this.getCookieValue(myCookies,cookieName,"not found");
  PrintWriter out = res.getWriter();
  if(this.username != null)
  {  
   //out.println("早上好，" + this.username + "！");
   return true;
  }else{
   out.println("登陸失敗！");
   return false;
   }

 }

 public String getUserName()
 {
  return this.username;
 }

 public static String getCookieValue(Cookie[] cookies,String cookieName,String defaultValue)
 {
  for(int i=0;icookies.length;i++) {
  Cookie cookie = cookies[i];
  if (cookieName.equals(cookie.getName()))
  return(cookie.getValue());
 }
  return(defaultValue);
 }
}

說明：此bean檢測cookie中的username，若不為空則說明已登錄，反之說明沒有登錄。方法不夠完善，您可以自行擴充。

六、在JRun中建立shopping服務器
打開JRun Administrator，新建shopping服務器，這里端口為8101。
將上文所述所有編譯后的class文件連同org包拷至JRun的shopping服務器所在目錄中的classes文件夾下，路徑為：

C:\JRun4\servers\shopping\default-ear\default-war\WEB-INF\classes\

七、建立jsp文件
應用DW，在C:\JRun4\servers\shopping\default-ear\default-war\目錄下新建如下的jsp文件：
index.jsp：

%@ page contentType="text/html;charset=gb2312" pageEncoding="gb2312" %>
html>
head>
title>Shopping123/title>
meta http-equiv="Content-Type" content="text/html; charset=gb2312">
link href="styles/shoppingstyle.css" rel="stylesheet" type="text/css">
/head>
body bgcolor="#FFFFFF" leftmargin="0" topmargin="0">
jsp:useBean id="checklogin" class="checkLogin" scope="page"/>
%
 boolean login = checklogin.check(request,response);
%>
table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0">
  tr bgcolor="#990000">
    td height="80" colspan="5">table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0">
        tr>
          td width="120">nbsp;/td>
          td class="caption">Shopping123/td>
          td width="200">nbsp;/td>
        /tr>
      /table>/td>
  /tr>
  tr>
    td width="200" align="center" valign="top">table width="100%" height="20" border="0" cellpadding="0" cellspacing="0">
        tr>
          td>nbsp;/td>
        /tr>
      /table>
   %
    if(!login){
   %>
      table width="90%" border="0" align="center" cellpadding="0" cellspacing="1" bgcolor="#CCCCCC">
   form name="form1" method="post" action="/servlet/login">
        tr align="center" bgcolor="#CCCCCC">
          td height="30" colspan="2" class="deepred">賣場入口/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">會員/td>
          td align="center" bgcolor="#FFFFFF">input name="username" type="text" id="username" size="10">/td>
        /tr>
        tr>
          td height="24" align="center" bgcolor="#FFFFFF">密碼/td>
          td align="center" bgcolor="#FFFFFF">input name="password" type="text" id="password" size="10">/td>
        /tr>
        tr>
          td height="24" align="center" bgcolor="#FFFFFF">a href="reg.jsp" target="_blank" class="red">注冊/a>/td>
          td align="center" bgcolor="#FFFFFF">input type="submit" name="Submit" value="進入">/td>
        /tr>
  /form>
      /table>
   %
    }
  else
  {
   out.println("您好，" + checklogin.getUserName() + "!");
  }
   %>
   /td>
 td width="1" valign="top" bgcolor="#CCCCCC">/td>
    td width="400">nbsp;/td>
 td width="1" valign="top" bgcolor="#CCCCCC">/td>
    td width="200">nbsp;/td>
  /tr>
  tr align="center" bgcolor="#990000">
    td height="60" colspan="5" class="white">copyrightcopy; 2003 Shopping123/td>
  /tr>
/table>
/body>
/html>

reg.jsp%@ page contentType="text/html;charset=gb2312" pageEncoding="gb2312" %>
html>
head>
title>Shopping123/title>
meta http-equiv="Content-Type" content="text/html; charset=gb2312">
link href="styles/shoppingstyle.css" rel="stylesheet" type="text/css">
/head>
body bgcolor="#FFFFFF" leftmargin="0" topmargin="0">
table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0">
  tr bgcolor="#990000">
    td height="80" colspan="5">table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0">
        tr>
          td width="120">nbsp;/td>
          td class="caption">Shopping123/td>
          td width="200">nbsp;/td>
        /tr>
      /table>/td>
  /tr>
  tr>
    td width="100" align="center" valign="top">nbsp;/td>
    td width="1" valign="top">/td>
    td width="400" align="center" valign="top">table width="100%" height="20" border="0" cellpadding="0" cellspacing="0">
        tr>
          td>nbsp;/td>
        /tr>
      /table>
      table width="100%" border="0" cellpadding="0" cellspacing="1" bgcolor="#CCCCCC">
   form action="regpost.jsp" method="post" name="form1">
        tr align="center">
          td height="30" colspan="2" bgcolor="#CCCCCC" class="deepred">會員注冊/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">會員/td>
          td align="center" bgcolor="#FFFFFF">input name="username" type="text" id="username" size="16">/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">密碼/td>
          td align="center" bgcolor="#FFFFFF">input name="password" type="password" id="password" size="16">/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">驗證密碼/td>
          td align="center" bgcolor="#FFFFFF">input name="confirm" type="password" id="confirm" size="16">/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">E-mail/td>
          td align="center" bgcolor="#FFFFFF">input name="email" type="text" id="email" size="16">/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">input type="submit" name="Submit" value="重寫">/td>
          td align="center" bgcolor="#FFFFFF">input type="submit" name="Submit2" value="注冊">/td>
        /tr>
  /form>
      /table>/td>
    td width="1" valign="top">/td>
    td width="100">nbsp;/td>
  /tr>
  tr align="center" bgcolor="#990000">
    td height="60" colspan="5" class="white">copyrightcopy; 2003 Shopping123/td>
  /tr>
/table>
/body>
/html>
 regpost.jsp：注冊表單提交頁面%@ page contentType="text/html;charset=gb2312" pageEncoding="gb2312" %>
%@ page import="reg"%>
html>
head>
title>Shopping123/title>
meta http-equiv="Content-Type" content="text/html; charset=gb2312">
link href="styles/shoppingstyle.css" rel="stylesheet" type="text/css">
/head>
body bgcolor="#FFFFFF" leftmargin="0" topmargin="0">
%
 String username = new String(request.getParameter("username").getBytes("ISO8859_1")).trim();
 String password = new String(request.getParameter("password").getBytes("ISO8859_1")).trim();
 String confirm = new String(request.getParameter("confirm").getBytes("ISO8859_1")).trim();
 String email = new String(request.getParameter("email").getBytes("ISO8859_1")).trim();
%>
table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0">
  tr bgcolor="#990000">
    td height="80" colspan="5">table width="100%" height="100%" border="0" cellpadding="0" cellspacing="0">
        tr>
          td width="120">nbsp;/td>
          td class="caption">Shopping123/td>
          td width="200">nbsp;/td>
        /tr>
      /table>/td>
  /tr>
  tr>
    td width="100" align="center" valign="top">nbsp;/td>
    td width="1" valign="top">/td>
    td width="400" align="center" valign="top">
table width="100%" height="20" border="0" cellpadding="0" cellspacing="0">
        tr>
          td>nbsp;/td>
        /tr>
      /table>
jsp:useBean id="regID" class="reg" scope="session"/>
%
 if(regID.reg(username,password,confirm,email))
 {
  out.print("ok");
  String newID = regID.getID() + ";
%>
      table width="100%" border="0" cellpadding="0" cellspacing="1" bgcolor="#CCCCCC">
        tr align="center">
          td height="30" colspan="2" bgcolor="#CCCCCC" class="deepred">恭喜您，注冊成功！/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">編號/td>
          td align="center" bgcolor="#FFFFFF">%=newID%>/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">會員/td>
          td align="center" bgcolor="#FFFFFF">%=username%>/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">密碼/td>
          td align="center" bgcolor="#FFFFFF">%=password%>/td>
        /tr>
        tr>
          td width="50%" height="24" align="center" bgcolor="#FFFFFF">E-mail/td>
          td align="center" bgcolor="#FFFFFF">%=email%>/td>
        /tr>
      /table>
%
  out.print("br>");
  out.print("a href=javascript:window.close()>關閉/a>");
 }else{
  out.print("注冊失??！br>");
  out.print("該用戶名已有人使用，請使用另外的用戶名！");
  out.print("a href=javascript:history.go(-1)>返回/a>");
 }
%>
   /td>
    td width="1" valign="top">/td>
    td width="100">nbsp;/td>
  /tr>
  tr align="center" bgcolor="#990000">
    td height="60" colspan="5" class="white">copyrightcopy; 2003 Shopping123/td>
  /tr>
/table>
/body>
/html>
 至此，我們已經完成了一個用戶注冊、登錄的系統。 因為這是本人自己邊學邊做完成的，所以代碼一定有很多不完善的地方，歡迎大家批評指正。 以上所有代碼均經本人測試通過。