Hibernate Mapping

Hibernate ORM
1

I’m trying to do something that I don’t know if it’s possible.

I’ll put you in context.

I’m trying to save an Object with this structure.

class ObjectOne {

   @Id...@GenerateValue...
   private Integer Id;
   private String name;

   @OneToMany(mappedBy = "objectOne", cascade = CascadeType.ALL, orphanRemoval = true, fetch = FetchType.EAGER)
   private final List<ObjectTwo> objects = new ArrayList<>();
   ...
}

class ObjectTwo {

   @EmbeddedId
   private ObjectTwoId id;
   private String description;

   @ManyToOne(fetch = FetchType.LAZY)
   @JoinColum(name = "object_one_id", referencedColumnName = "id" , nullable = false)
   private ObjectOne objectOne;
   ...
}

@Embeddable
class ObjectTwoId {
   private Integer objectOneId;
   private String languageIso;
}

With this structure I trying to save a new ObjectOneEntity with a ObjectTwoEntity list.

I was hoping Hibernate could handle this by first doing an INSERT of ObjectOneEntity, and assigning it to ObjectTwoEntity with the generated id of ObjectOneEntity.

But unfortunately, it is first trying to insert the nested class ObjectTwoEntity and it gives me an error because it cannot assign a null value to the id ObjectOneId of the embeddedId class.

Is there any way to delegate this work to Hibernate or should I do the inserts separately?

2

@byDiro_Cwl using a @GeneratedValue identifier of an associated entity as part of your primary key is not a good idea. I would suggest either switching your ObjectOne entity to use an assigned identifier, or split the persisting of the two objects so that ObjectOnes are always flushed to the database before being assigned to ObjectTwo.