org.hibernate.loader.plan.spi

Interface BidirectionalEntityReference

All Superinterfaces:

EntityReference, FetchSource

All Known Implementing Classes:

BidirectionalEntityReferenceImpl

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.

Author:

Steve Ebersole

Method Summary

Modifier and Type	Method and Description
String	getQuerySpaceUid() The query space UID returned using getQuerySpaceUid() must be the same as returned by #getTargetEntityReference()#getQuerySpaceUid()
EntityReference	getTargetEntityReference() Get the targeted EntityReference

Methods inherited from interface org.hibernate.loader.plan.spi.EntityReference

getEntityPersister, getIdentifierDescription

Methods inherited from interface org.hibernate.loader.plan.spi.FetchSource

getBidirectionalEntityReferences, getFetches, getPropertyPath, resolveEntityReference

Method Detail

getTargetEntityReference

EntityReference getTargetEntityReference()

Get the targeted EntityReference

Returns:

The targeted EntityReference

getQuerySpaceUid

String getQuerySpaceUid()

The query space UID returned using getQuerySpaceUid() must be the same as returned by #getTargetEntityReference()#getQuerySpaceUid()

Specified by:

getQuerySpaceUid in interface EntityReference

Specified by:

getQuerySpaceUid in interface FetchSource

Returns:

The query space UID.