void addFrom(String name, JoinSequence joinSequence) throws QueryException {
   fromTypes.add(name);
   addJoin(name, joinSequence);
 }
 void addFromJoinOnly(String name, JoinSequence joinSequence) throws QueryException {
   addJoin(name, joinSequence.getFromPart());
 }
 void addFromCollection(String name, String collectionRole, JoinSequence joinSequence)
     throws QueryException {
   // register collection role
   addCollection(name, collectionRole);
   addJoin(name, joinSequence);
 }