mybatis使用association分步查询关联属性查询

1、我们的程序是要查询员工信息的时候查询出相应的部门信息。

3、定义员工信息返回的resultMap。<resultMap type="com.gwolf.bean.Employee" id="MyEmpByStep"> <id column="emp_id" property="empId"/> <result column="emp_name" property="empName"/> <result column="gender" property="gender"/> <result column="email" property="email"/> <result column="emp_name" property="empName"/> <association property="department" select="com.gwolf.dao.DepartmentMapper.getDepartmentById"></association> </resultMap>

5、编写单元测试类。@Test public void test1() throws Exception { String resource = "mybatis-config.xml"; InputStream inputStream = Resources.getResourceAsStream(resource); SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream); SqlSession sqlSession = sqlSessionFactory.openSession(); try { EmployeeMapper employeeMapper = sqlSession.getMapper(EmployeeMapper.class); Map<Integer,Object> employee = employeeMapper.getEmpByIdReturnMap(1); System.out.println(employee); }finally { sqlSession.close(); } }