I've got a domain model which looks a bit like this:

A
==
B getB()
C getC()

B
==
String getName()

C
==
D getD()

D
==
String getName()
String getTown()

and I'm trying to create the following where clause using the Criteria API:

where c.d.name = "wibble" or (c.d.town="blah" and b.name="wobble")

The code I'm using is this:

Criteria rootCriteria = session.createCriteria(A.class);
Criteria or = rootCriteria.add(Restrictions.disjunction());
or.createCriteria("c")
.createCriteria("d")
.add(Restrictions.eq("name", "wibble"));
Criteria and = or.add(Restrictions.conjunction());
and.createCriteria("c")
.createCriteria("d")
.add(Restrictions.eq("town", "blah");
and.createCriteria("b")
.add(Restrictions.eq("name", "wobble"));

List result = rootCriteria.list();

However, running this gives me the following exception:
org.hibernate.QueryException: duplicate association path: c
at org.hibernate.loader.criteria.CriteriaQueryTranslator.createAssociationPathCriteriaMap(CriteriaQueryTranslator.java:141)
at org.hibernate.loader.criteria.CriteriaQueryTranslator.<init>(CriteriaQueryTranslator.java:80)
at org.hibernate.loader.criteria.CriteriaLoader.<init>(CriteriaLoader.java:58)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1550)
at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:283)

Is there any way to restructure my criteria to give me the where clause I'm looking for?


Hibernate version: 3.2.5

Right, I've solved this - in case anyone else comes across this post, this is the code snippet - basically you need to use aliases:

Criteria rootCriteria = session.createCriteria(A.class);
rootCriteria.createAlias("b", "b");
rootCriteria.createAlias("c", "c");
rootCriteria.createAlias("c.d", "d");

rootCriteria.add(Restrictions.disjunction()
.add(Restrictions.eq("d.name", "wibble"))
.add(Restrictions.conjunction()
.add(Restrictions.eq("d.town", "blah"))
.add(Restrictions.eq("b.name", "wobble")));

List result = rootCriteria.list();