【图】在jsp中用bean和servlet联合实现用户注册、登录

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在jsp中用bean和servlet联合实现用户注册、登录

作者：imagebear
版权：imagebear

本例需要的软件和运行环境：
1、Windows2000 Server操作系统
2、jdk1.4
3、JCreator2.5（java源码编辑调试器，吐血推荐！）
4、Macromedia JRun MX
5、Macromedia Dreamweaver MX（非必需）
6、MySQL数据库（最好安装MySQL Control Center）

一、数据库设计
用MySQL Control Center打开MySQL数据库，新建数据库shopping，在其下新建表tbl_user，其中各字段设置如下：

二、编写连接数据库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);//加载数据库驱动程序
   this.conn = DriverManager.getConnection(sql_url + "/" + sql_DBName + "?user=" + user + "&password=" + pwd + "&useUnicode=true&characterEncoding=gb2312");
   this.stmt = this.conn.createStatement();
}catch(Exception e){
   System.out.println(e.toString());
}
}

                //执行查询操作
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;
}
}

                //执行数据的插入、删除、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;
}
}

                //结果集指针跳转到某一行
public boolean rs_absolute(int row)
{
try{
   this.rs.absolute(row);
   return true;
}cat