JPA orphan removal does not work for OneToOne relations

Question

Does anyone have a workaround for this issue: https://hibernate.atlassian.net/browse/HHH-9663?

I am also facing a similar issue. When I created one-sided (no reverse reference) one to one relationship between two entities and set the orphan removal attribute to true, the referenced object is still in the database after setting the reference to null.

Here is the sample domain model:

@Entity
public class Parent {
  ...
  @OneToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL, orphanRemoval = true)
  @JoinColumn(name = "child_id")
  private Child child;
  ...
}

@Entity
public class Child {
  ...
  @Lob
   private byte[] data;
  ...
}

I am currently working around this by manually deleting orphans.

Answer 1

Cascading only makes sense for entity state transitions that propagate from a Parent to a Child. In your case, the Parent was actually the child of this association (having the FK).

Try with this mapping instead:

@Entity
public class Parent {
  ...
  @OneToOne(
      fetch = FetchType.LAZY, 
      cascade = CascadeType.ALL, 
      orphanRemoval = true, 
      mappedBy = "parent"
  )
  private Child child;
  ...
}

@Entity
public class Child {

    @OneToOne
    @JoinColumn(name = "parent_id")
    private Parent parent;

    ...
    @Lob
    private byte[] data;
    ...
}

And to cascade the orphan removal, you now need to:

Parent parent = ...;
parent.getChild().setParent(null);
parent.setChild(null);

Or even better, confgiure the setChild method in the Parent entity class to set both associations:

public void setChild(Child child) {
    if (child == null) {
        if (this.child != null) {
            this.child.setParent(null);
        }
    }
    else {
        child.setParent(this);
    }
    this.child = child;
}