登陆的dao层

package com.wh.dao;

import com.wh.entity.User;

public interface LoginDao {
public Boolean login(User user);

}

package com.wh.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import com.wh.entity.User;
import com.wh.utils.DBUtil;

public class LoginDaoImpl implements LoginDao {

	@Override
	public Boolean login(User user) {
		// TODO Auto-generated method stub
		Boolean result=false;
		Connection connection=null;
		PreparedStatement preparedStatement=null;
		ResultSet resultSet=null;
		try {
			connection=DBUtil.getConnection();
			String sql=" select*from user where username=? and password=? ";
			preparedStatement=connection.prepareStatement(sql);
			preparedStatement.setString(1, user.getUsername());
			preparedStatement.setString(2, user.getPassword());
			resultSet=preparedStatement.executeQuery();
			if(resultSet.next()){
				return result=true;
			}
			else {
				return result=false;
			}
			
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return result=false;
		}
		finally {
			try {
				resultSet.close();
				preparedStatement.close();
				connection.close();
			} catch (SQLException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			
		}
	}

}