SSM11.4【Mybatis：Mybatis相关API】

 

 

 

 

 

userMapper.xml

+

<!--根据id进行查询-->
    <select id="findById" resultType="user" parameterType="int">
        select * from user where id=#{id}
    </select>

MybatisTest

+

    @Test
    public void test5() throws IOException {
        //模拟User对象
        User user = new User();
        user.setUsername("tom");
        user.setPassword("abc");

        //加载Mybatis核心配置文件
        InputStream resourceAsStream = Resources.getResourceAsStream("sqlMapConfig.xml");
        //获取session工厂对象
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
        //获取session会话对象
        SqlSession sqlSession = sqlSessionFactory.openSession(true); //设置为true，那么不需要手动提交事务
        //执行操作
        sqlSession.insert("userMapper.save", user);
        //提交事务
//        sqlSession.commit();
        //释放资源
        sqlSession.close();
    }

    /**
     * 查询一条数据
     * @throws IOException
     */
    @Test
    public void test6() throws IOException {
        //加载Mybatis核心配置文件
        InputStream resourceAsStream = Resources.getResourceAsStream("sqlMapConfig.xml");
        //获取session工厂对象
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
        //获取session会话对象
        SqlSession sqlSession = sqlSessionFactory.openSession();
        //执行操作
        User user = sqlSession.selectOne("userMapper.findById", 2);
        //打印结果
        System.out.println(user); //User{id=2, username='lisi', password='345'}
        //释放资源
        sqlSession.close();
    }