Java基础|mybatis plus一对多查询（经典案例）开发语言|java

一、条件

查询班级表返回所有学生信息（一对多问题）

二、数据库班级class_info

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【Java基础|mybatis plus一对多查询（经典案例）】学生student

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二、代码实现

实体类ClassInfo.java

@Data public class ClassInfo {private Long id; private String name; private String nameTest; private List studentList; }

ClassInfoMapper.xml

select * from class_info

关联StudentMapper.xml中的子查询

SELECT * FROM student s where class_info_id = #{id1} or name = #{name}

ClassInfoMapper.java

public interface ClassInfoMapper extends BaseMapper {IPage listAllWithStudent(IPage page); }

ClassInfoService.java

public interface ClassInfoService extends IService {IPage listAllWithStudent(IPage page); }

ClassInfoServiceImpl.java

@Service public class ClassInfoServiceImpl extends ServiceImpl implements ClassInfoService { @Autowired private StudentService studentService; @Override public IPage listAllWithStudent(IPage page) { return this.baseMapper.listAllWithStudent(page); } }

ClassInfoController.java

@Controller @RequestMapping("classInfo") public class ClassInfoController {@Autowired private ClassInfoService classInfoService; @RequestMapping("listAllWithStudent") @ResponseBody public IPage listAllWithStudent(Integer pageNo,Integer pageSize){ Page page = new Page<>(pageNo,pageSize); return classInfoService.listAllWithStudent(page); }}