//Technically, the subject of the triple is not a container of the reference,
//however, the subject is exported and represents (the name) of the triple.
//Using its URI in the reference description ensures that "find references" gives
//a (more) meaningful label in the search result view
private URI getExportedSubjectUri(EObject ref) {
Triples triples = EcoreUtil2.getContainerOfType(ref, Triples.class);
if(triples!=null){
Subject subject = triples.getSubject();
if(subject instanceof Resource){
org.eclipse.emf.ecore.resource.Resource res = subject.eResource();
return res.getURI().appendFragment(res.getURIFragment(subject));
}
}