Package org.hibernate.loader.plan.spi

Interface BidirectionalEntityReference

  • All Superinterfaces:
    EntityReference, FetchSource
    public interface BidirectionalEntityReference
extends EntityReference
    Represents the circular side of a bi-directional entity association. Wraps a reference to the associated (target) EntityReference.

    The EntityReferenceAliases for this object is the same as for its target EntityReference, and can be looked up via AliasResolutionContext.resolveEntityReferenceAliases(String) using the value returned by getQuerySpaceUid(). This relies on reference lookups against the EntityReference instances, therefore this allows representation of the circularity but with a little protection against potential stack overflows. This is unfortunately still a cyclic graph. An alternative approach is to make the graph acyclic (DAG) would be to follow the process I adopted in the original HQL Antlr v3 work with regard to always applying an alias to the "persister reference", even where that meant creating a generated, unique identifier as the alias. That allows other parts of the tree to refer to the "persister reference" by that alias without the need for potentially cyclic graphs (think ALIAS_REF in the current ORM parser). Those aliases can then be mapped/catalogued against the "persister reference" for retrieval as needed.