新手提问：关于struts2.0的数据操作。

[colie_li]

刚学习struts2，想做一个连接数据库的用户登录验证，就是输入账号，然后通过该账号去数据库查找密码；如果查找的密码跟输入的密码一样则登陆成功，否则不成功；
action:

package com.test.login;
import java.sql.*;

import com.opensymphony.xwork2.ActionSupport;

public class Login extends ActionSupport 
{
	private  String  username;
	private  String  password;
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
		String a="sadad";
		 System.out.print(a);
	}
	public String  DB()	
	{	
	    Connection con = null;
		   Statement sql=null;
		   ResultSet rs=null;
		   try{ 
			    Class.forName( "sun.jdbc.odbc.JdbcOdbcDriver");
		        con=DriverManager.getConnection("jdbc:odbc:sum","","");
		       }catch(Exception e){System.out.println("数据库连接错误！"); 
		try{      
			     String sqle="select pass from student where studentid='"+username+"'";
		         rs=con.createStatement().executeQuery(sqle);
		         rs.next();
		         String a=rs.getString("pass");
		        
		         if(rs.next())
		         {
		         if(a==password) 
		        	 {
		        		 return this.SUCCESS;
		        	 }
		        	 else
		        	 {
		        		 this.addFieldError("password", "password input worng");
		        		 return this.INPUT;
		        	 }
		         }
		         else
		         {
		        	 this.addFieldError("username", "username input worng");
		        	 return this.INPUT;
		         }		       
		}catch(Exception e1){System.out.println(e1.toString()); 
		}	
		}	
		return null;	
	}
	@Override
	public String execute() throws Exception {
		
		return "sucess";
	}
	@Override
	public void validate() 
	{
		
		if(null==this.getUsername()||"".equals(this.getUsername().trim()))
		{
			this.addFieldError("username", "username err");
		}
		if(null==this.getPassword()||"".equals(this.getPassword().trim()))
		{
			this.addFieldError("password", "password err");
		}
	}
		
}
	
		

xml；

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
    "http://struts.apache.org/dtds/struts-2.0.dtd">

<struts>
     <package name="struts2" extends="struts-default">
     
       <action name="login" class="com.test.login.Login"  >
            <result name="input">/login.jsp</result>
            <result name="sucess">/index.jsp</result>
       </action> 
    
    
     </package>
</struts>

运行的结果是不输入东西提示username err或password err错误，然后无论是输入对的密码还是输入错的密码显示的是空白页；各位牛人解答下；

[加嘞个油]

<result>/index.jsp</result>

这样。

[wang7535067]

try{
String sqle="select pass from student where studentid='"+username+"'";
rs=con.createStatement().executeQuery(sqle);
rs.next();
String a=rs.getString("pass");

if(rs.next())
{
if(a==password)
{
return this.SUCCESS;
}
else
{
this.addFieldError("password", "password input worng");
return this.INPUT;
}
}
去掉这一句 if(rs.next())