While requesting an entity with a broken OneToOne relationship, no row is returned and no error is raised.
The ObjectNotFoundException is logged at INFO level.

Giving the following entities, if a MainEntity has a child_id which doesn't exist, null is returned, whereas we could expect an ObjectNotFoundException to be thrown.

@Entity
public class MainEntity {
	@Id Integer id;
	@OneToOne ChildEntity child;
}


@Entity
public class ChildEntity {
	@Id Integer id;
}

Sample code attached with unit test attached.