hibernate表关联问题

Question

teacher表：id、name、age、group_id
book表：id、name、description、teacher_id
关系：一对多
---------------------------------------------------------------------------------------------------------
问题：我想 通过book的id查询到对应的book信息和teacher信息，他们之间在建立实体类的时候应该如何关联？

Answer 1

select * from book where id = xxx; select * from teacher where id = (select teacher_id from book where id = xxx);

Answer 2

实体类就按照表字段建，然后传bookid查book数据取得teacher_id查teacher表，数据不就都出来了