@Override
 public QuantitySearchList handleQuantity(final PersistentQuantity quantity)
     throws PersistenceException {
   final QuantitySearchList ret = new QuantitySearchList();
   ret.add(quantity);
   return ret;
 }
 @Override
 public QuantitySearchList handleCompoundQuantity(
     final PersistentCompoundQuantity compoundQuantity) throws PersistenceException {
   final QuantitySearchList ret = new QuantitySearchList();
   final Iterator<PersistentQuantity> i = compoundQuantity.getParts().iterator();
   while (i.hasNext()) {
     final PersistentQuantity curQuantity = i.next();
     ret.add(curQuantity);
   }
   return ret;
 }