Mybatis 注解开发

public interface UserMapper {
    @Update("update user set name=#{name},password=#{password} where id=#{id}")
    public void update(User user) ;

    @Insert("insert into user values(#{id},#{name},#{password},null,null)")
    public void insert(User user) ;

    @Delete("delete from user where id=#{id}")
    public  void delete(int id) ;

    @Select("select * from user where id=#{id}")
    public User findById(int id) ;

    @Select("select * from user")
    public List findAll() ;

}

public interface OrderMapper {
    @Select("select * from orders")
    @Results({
            @Result(column = "id",property = "id"),
            @Result(column = "date",property = "ordertime"),
            @Result(
                    property = "user", //要封装的属性名称
                    column = "uid", //根据那个字段去查询user表的数据
                    javaType = User.class, //要封装的实体类型
                    //select属性 代表查询那个接口的方法获得数据
                    one = @One(select = "com.itheima.mapper.UserMapper.findById")
            )
    })
    public List findAll();
}

public class test {
    private UserMapper mapper;
    private SqlSession sqlSession;

    @Before
    //前置增强
    public void before() throws IOException {
        InputStream resourceAsStream = Resources.getResourceAsStream("VI/SqlMapConfig.xml");
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(resourceAsStream);
        sqlSession = sqlSessionFactory.openSession(true);//自动提交
        mapper = sqlSession.getMapper(UserMapper.class);
    }

    @After
    //后置增强
    public void after() {
        sqlSession.close();
    }

    @Test
    public void testInsert() {
        mapper.insert(new User(5,"薛之谦","yeyeye"));
    }

    @Test
    public void testDelete() {
        mapper.delete(5);
    }

    @Test
    public void testUpdate() {
        mapper.update(new User(5,"薛之谦","wawawaw"));
    }

    @Test
    public void testFindById() {
        User user = mapper.findById(5);
        System.out.println(user);
    }

    @Test
    public void testFindAll() {
        List userList = mapper.findAll();
        System.out.println(userList);
    }
}

注意：Mybatis配置文件中的映射关系仍需声明：