@Override
 public Iterable<String> getCompletionProposals(int pos) {
   Iterable<String> result = super.getCompletionProposals(pos);
   if (result != null) {
     return result;
   }
   for (OrmSpecifiedPrimaryKeyJoinColumn column : this.getPrimaryKeyJoinColumns()) {
     result = column.getCompletionProposals(pos);
     if (result != null) {
       return result;
     }
   }
   return null;
 }
 public XmlPrimaryKeyJoinColumn extractResourceElement(
     OrmSpecifiedPrimaryKeyJoinColumn contextElement) {
   return contextElement.getXmlColumn();
 }