String加载配置-->阿帕奇包下Resources.getResourceAsStream()流
-->三部曲读取
-->工厂===new SqlSessionFactoryBuilder().build(in)方法把in拿进来;
-->Sqlsession类
--->mapper返回用户，--->userList返回结果--->遍历结果

import com.xuwen.mapper.UserMapper;
import com.xuwen.pojo.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 org.junit.Test;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

/**
 * author:xuwen
 * Created on 2021/7/28
 */
//test
public class MyTest {

    @Test
    public void test1() throws IOException {
        String resourcesFile = "mybatis-config.xml";
        InputStream in = Resources.getResourceAsStream(resourcesFile);
        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(in);
        SqlSession sqlSession = sessionFactory.openSession(true);

        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        List<User> userList = mapper.selectUser();
        for (User items : userList) {
            System.out.println(items);
        }


    }
}