userlogindao.java

学生信息管理系统

package dao;
import java.sql.*;

import vo.*;
import conn.*;

public class UserLoginDao
{
	public UserLoginDao()
	{
		
	}

	public boolean checkUser(String name,String pass)
	{
		boolean isright=false;
	
		try
		{
			Connection conn = ConnectDB.getConnection();
			Statement stmt =conn.createStatement();
			
			String sql="select * from users where userName='"+name+"'and password='"+pass+"'";
			ResultSet rs=stmt.executeQuery(sql);
			if(rs.next())
			{
				isright=true;
			}
			conn.close();
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	
		return isright;
	}

	public UserVO getUser(String userName)
	{
		ResultSet rs=null;
		UserVO user=null;
		try
		{
			user=new UserVO();
			Connection conn = ConnectDB.getConnection();
			Statement stmt =conn.createStatement();
			rs=stmt.executeQuery("select * from users where userName='"+userName+"'");
			if(rs.next())
			{
				user.setUserName(rs.getString("userName"));
				user.setPassword(rs.getString("password"));
				user.setType(rs.getString("type"));
				
			}
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		return user;
	}
	public void changePassword(String userName,String newpassword)
	{
		ResultSet rs=null;
		try
		{
			Connection conn=ConnectDB.getConnection();
			Statement stat=conn.createStatement();
			rs=stat.executeQuery("select * from users where userName='"+userName+"'");
			if(rs.next())
			{
				ConnectDB.executeUpdate("update users set password='"+newpassword+"'where userName='"+userName+"'");
			}
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
}