Description Luca Graf 2011-10-09 19:14:35 EDT

Build Identifier: 2.2.0.v20110202-r8913

Iterating over @Embeddable objects (@ElementCollection mapped as Set) who holds an entity relation (many-to-one) can cause duplicate-key exceptions. 
Under certain circumstances eclipselink try to insert also persistent 'relation objects' from the embeddable again (triggers duplicate-key exception).

Sample Model:
EntityParent 1-n > EmbeddableChild n-1 > EntityChildRelation

Sample code that causes a duplicate exception:
List<Parent> parents = em.createNamedQuery( "findAllParents", Parent.class ).getResultList();
for ( Parent parent : parents ) {
   for ( Child child : parent.getChildren() ) {
      child.getEntityRelation();
   }
   em.flush();
}

I attached a simple maven project, that contains entity classes and a unit-test (runnable in a se environment) with that the problem can be reproduced.

There still exists a more detailed forum thread about the issue: http://www.eclipse.org/forums/index.php/t/242755/.

Please note that the problem seemed to be non-deterministic (the test fails only 'most' of the time).

Reproducible: Sometimes

Steps to Reproduce:
1. Run the attached unit-test.