Set newEntities = new TreeSet(new PropertyListSet());
Set newEntities = new HashSet();
  public void removeEntity(EOEntity _entity) {    myDeletedEntityNames.add(_entity.getName());    Set oldEntities = myEntities;    Set newEntities = new TreeSet(new PropertyListSet());    newEntities.addAll(myEntities);    newEntities.remove(_entity);    myEntities = newEntities;    firePropertyChange(EOModel.ENTITIES, oldEntities, myEntities);    _entity._setModel(null);  }