userdao.java

用ssh作的一个小例子

package com.blue.manage.DAO;

import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
import com.bluedot.usermanage.bean.User;

public class UserDAO {
	private static Connection connection;
	private static Properties properties ;
	
	
	public static void link(){
		properties = new Properties();
		try{
			properties.load(Thread.currentThread().getContextClassLoader().
					getResourceAsStream("aaa.properties"));
		}catch(IOException e){
			e.printStackTrace();
		}
		String url = properties.getProperty("url");
		String driver = properties.getProperty("drv");
		String username = properties.getProperty("name");
		String password = properties.getProperty("password");
		
		try{
			Class.forName(url);
			connection = DriverManager.getConnection(
					driver, username,password);
		}catch(Exception e){
			e.printStackTrace();
		}
		
	}
	
	public static void add(User u){
		link();
		try{
			int i=1;
			String sql = "insert into users(user_name,password,name,sex,email,birthday) values(?,?,?,?,?,?)";
			PreparedStatement preparedStatement =connection.prepareStatement(sql);
			
			preparedStatement.setString(i++,u.getUsername());
			preparedStatement.setString(i++,u.getPassword());
			preparedStatement.setString(i++,u.getName());
			preparedStatement.setString(i++,u.getSex());
			preparedStatement.setString(i++,u.getEmail());
			preparedStatement.setDate(i++, u.getBirthday());
			preparedStatement.execute();
			
			preparedStatement.close();
		}catch(SQLException e){
			throw new RuntimeException(e);
		}finally{
			if(connection!=null){
				try {
					connection.close();
				} catch (SQLException e1) {
				}
			}
		}
	}
	
	public static boolean logon(String name,String pw){
		link();
		boolean tag = false;
		try{
		    Statement statement = connection.createStatement();
		    ResultSet resultSet = statement.executeQuery("select * from users where user_name='"+name+"' and password ='"+pw+"'");
		    //select * from AUTHENTICATIONS where USER_NAME='marshal' or 'x'='x' and PASSWORD='dddd';
		    if(resultSet.next()){
		    	tag = true;
		    }
		}catch(SQLException e){
			throw new RuntimeException(e);
		}finally{
			if(connection!=null){
				try {
					connection.close();
					
				} catch (SQLException e1) {
				}
			}
		}
		return tag;
	}

}