请给一个servlet身份验证的代码，谢谢，在线等

[znjq1001]

谢谢了~

[icecloud]

package works;

import java.util.*;
import java.sql.*;

//中文
public class LoginBean {

private String username = null;
private String password = null;
private String usertype = null;

public boolean doLogin() {
boolean bologin = false;
try {
String sql = "select * from t_user where username='" + username + "' and password='" + password + "'";
//System.out.print("test");
JdbcBean db = new JdbcBean();
ResultSet rs = db.executeQuery(sql);
if (rs.next()) {
this.username = rs.getString("username");
this.usertype = rs.getString("usertype");
bologin = true;
}
else
this.username = null;

}
catch (Exception e) {
System.err.println("LoginBean.doLogin(): " + e.getMessage());
}
finally {
//返回值
return bologin;
}

}

//Access sample property
public String getUsername() {
if (this.doLogin())
return username;
else
return null;
}

public String getUsertype() {
if (this.doLogin())
return usertype;
else
return null;
}


//Access sample property
public void setUsername(String newValue) {
if (newValue != null) {
this.username = newValue;
}
}

public void setPassword(String newValue) {
if (newValue != null) {
this.password = newValue;
}
}

}

[icecloud]

注：该代码是我写的第一个jsp程序里面的bean
写得很烂，仅作参考~~ jdbcbean如下，到处都是随便看看


package works;
//我的包

import java.sql.*;

public class JdbcBean {
private String sDBDriver="sun.jdbc.odbc.JdbcOdbcDriver";
private String connStr="jdbc:odbc:Mydata";
private Connection conn=null;
private Statement stmt=null;
private String username="";
private String password="";
private ResultSet rs=null;


public JdbcBean() throws SQLException {
try {
//注册数据库驱动程序为Oracle驱动

Class.forName(sDBDriver);
conn = DriverManager.getConnection(connStr,username,password);
}
catch(java.lang.ClassNotFoundException e) {
System.err.println("jdbcBean(): " + e.getMessage());
}
}



//executeQuery方法用于进行记录的查询操作

//入口参数为sql语句，返回ResultSet对象
public ResultSet executeQuery(String sql)
{
try {
//建立数据库连接

stmt = conn.createStatement(java.sql.ResultSet.TYPE_SCROLL_INSENSITIVE,java.sql.ResultSet.CONCUR_READ_ONLY);

//执行数据库查询操作
rs = stmt.executeQuery(sql);
}
catch (SQLException ex) {
System.err.println("db.executeQuery: " + sql + "" + ex.getMessage());
}
finally{
return rs;
}
}

//executeUpdate方法用于进行add或者update记录的操作

//入口参数为sql语句，成功返回true，否则为false
public boolean executeUpdate(String sql) {
boolean bupdate = false;
rs = null;
try {
//建立数据库连接，其它参数说明同上面的一样
stmt = conn.createStatement();
int rowCount = stmt.executeUpdate(sql);
//如果不成功，bupdate就会返回0
if (rowCount != 0)
bupdate = true;
}
catch (SQLException ex) {
//打印出错信息
System.err.println("db.executeUpdate: " + ex.getMessage());
}
finally {
return bupdate;
}
}

protected void finalize(){

}


}

[znjq1001]

谢谢你的回复，我想做一个servlet的验证，通过用户输入的不同信息，转向不同的页面。