Я хочу удалить использование объектов висячей строки, в спящем режиме и JPA на many-many отношениях, но все, что я нашел, было этим атрибутом атрибут. org.hibernate.annotations. CascadeType. DELETE_ORPHAN (т.е. @Cascade (оценивают = {org.hibernate.annotations. CascadeType. DELETE_ORPHAN)), который работает только на связи "один ко многим".
Я хочу знать, могу ли я удалить висячей строки на своих many-many отношениях.
На самом деле, я сделал тест со следующими сущностями:
@Entity
public class Person {
@Id
@GeneratedValue
private Long id;
private String firstName;
private String lastName;
@ManyToMany
@Cascade(value = org.hibernate.annotations.CascadeType.DELETE_ORPHAN)
private Set<Role> roles = new HashSet<Role>();
//...
}
@Entity
public class Role {
@Id
@GeneratedValue
private Long id;
private String name;
@ManyToMany(mappedBy = "roles")
private Set<Person> persons = new HashSet<Person>();
//...
}
И со следующим набором данных:
<dataset>
<PERSON id="1" firstname="john" lastname="doe"/>
<PERSON id="2" firstname="clark" lastname="kent"/>
<PERSON id="3" firstname="james" lastname="bond"/>
<ROLE id="1" name="foo"/>
<ROLE id="2" name="bar"/>
<ROLE id="3" name="boo"/>
<ROLE id="4" name="baz"/>
<PERSON_ROLE persons_id="1" roles_id="1"/>
<PERSON_ROLE persons_id="1" roles_id="2"/>
<PERSON_ROLE persons_id="2" roles_id="2"/>
<PERSON_ROLE persons_id="2" roles_id="3"/>
<PERSON_ROLE persons_id="3" roles_id="1"/>
<PERSON_ROLE persons_id="3" roles_id="4"/>
</dataset>
Следующий метод проверки:
@Test
public void testCascadeDeleteOrphanOnDelete() {
Person person = entityManager.find(Person.class, 1L);
entityManager.remove(person);
ReflectionAssert.assertPropertyLenientEquals("id", Arrays.asList(2, 3), findAllPersons());
ReflectionAssert.assertPropertyLenientEquals("id", Arrays.asList(3, 4), findAllRoles());
}
private List<Person> findAllPersons() {
return entityManager.createQuery("from Person").getResultList();
}
private List<Role> findAllRoles() {
return entityManager.createQuery("from Role").getResultList();
}
Просто проходит. Ниже вывод:
Hibernate: select personx0_.id as id17_0_, personx0_.firstName as firstName17_0_, personx0_.lastName as lastName17_0_ from Person personx0_ where personx0_.id=? Hibernate: select roles0_.persons_id as persons1_1_, roles0_.roles_id as roles2_1_, rolex1_.id as id18_0_, rolex1_.name as name18_0_ from Person_Role roles0_ left outer join Role rolex1_ on roles0_.roles_id=rolex1_.id where roles0_.persons_id=? Hibernate: delete from Person_Role where persons_id=? Hibernate: delete from Role where id=? Hibernate: delete from Role where id=? Hibernate: delete from Person where id=? Hibernate: select personx0_.id as id17_, personx0_.firstName as firstName17_, personx0_.lastName as lastName17_ from Person personx0_ Hibernate: select rolex0_.id as id18_, rolex0_.name as name18_ from Role rolex0_