<?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPE configuration

        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"

        "http://mybatis.org/dtd/mybatis-3-config.dtd">

<configuration>

    <!--配置环境-->

    <environments default="mysql">

        <environment id="mysql">

            <!--配置事务的类型-->

            <transactionManager type="JDBC"></transactionManager>

            <!--配置数据源（连接池）-->

            <dataSource type="POOLED">

                <!--配置连接数据库的4个基本信息-->

                <property name="driver" value="com.mysql.jdbc.Driver"/>

                <property name="url" value="jdbc:mysql://localhost:3306/mybatis"/>

                <property name="username" value="root"/>

                <property name="password" value=""/>

            </dataSource>

        </environment>

    </environments>

    <!--1.指定映射文件的位置，映射配置文件指的是每个dao独立的配置文件

             <mapper resources="com.ysong.dao.IUserDao.xml"></mapper>

        2.如果这里用的是注解，用class属性指定被注解的dao全限定名

            <mapper class="com.ysong.dao.IUserDao"></mapper>

    -->

    <mappers>

        <mapper class="com.ysong.dao.IUserDao"></mapper>

    </mappers>

</configuration>

package com.ysong.dao;

import com.ysong.domain.User;

import org.apache.ibatis.annotations.Select;

import java.util.List;

public interface IUserDao {

    @Select("select * from user")

    List<User> findAll();

}

/**

 * Copyright (C), 2015-2019, XXX有限公司

 * FileName: MyBatisTest

 * Author:   Administrator

 * Date:     2019/5/29 19:20

 * Description:

 **/

package com.ysong.test;

import com.ysong.dao.IUserDao;

import com.ysong.domain.User;

import org.apache.ibatis.io.Resources;

import org.apache.ibatis.session.SqlSession;

import org.apache.ibatis.session.SqlSessionFactory;

import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.InputStream;

import java.util.List;

public class MyBatisTest {

    public static void main(String[] args) throws Exception {

        //1.读取配置文件

        InputStream in = Resources.getResourceAsStream("SqlMapConfig.xml");

        //2.创建sqlSessionFactory工厂

        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();

        SqlSessionFactory factory = builder.build(in);

        //3.使用工厂生产sqlSession对象

        SqlSession session = factory.openSession();

        //4.使用sqlsession创建Dao接口的代理对象

        IUserDao userDao = session.getMapper(IUserDao.class);

        //5.使用代理对象执行方法

        List<User> users = userDao.findAll();

        for (User user : users) {

            System.out.println(user);

        }

        //6.释放资源

        session.close();

        in.close();

    }

}