保存父实体时子实体未持久化

Question

I have two entities with one-to-one relationships.

They are as follows,

@Entity
class Parent {

@Id
private String id;

@OneToOne(mappedBy = "parent", cascade = CascadeType.ALL)
private Child child;

// getter setter

}

@Entity
public class Child {

@Id
private String id;

@OneToOne(cascade = CascadeType.ALL,fetch=FetchType.LAZY)
@JoinColumn(name = "id", insertable = false, updatable = false)
private Parent parent;

// getter setter

}



@Service
public TestService {

@Autowired
private ParentRepository parentRepository;

public void testMethod() {

// Creating new ChildElement
Parent p = parentRepository.findById("ID1").get();
Child c = parent.getChild()
if(c == null) {
c = new Child() 
c.setId("ID2");
}
// set child with some property

p.setChild(c);

parentRepository.save(p);

}

}

This code is working when I am creating a new child entity for the first time. But when updating the child entity, it is not getting updated.

Could you please let me know if I am missing something.

Answer 1

I guess your problem is related to this line.

@JoinColumn(name = "id", insertable = false, updatable = false)
private Parent parent;

I mean insertable = false and updatable = false . When updatable and insertable are equal false it won't be updated I think.

Answer 2

You have to do bidirectional setting. Add below line after p.setChild(c).

C.setParent(p)