public void test() {
   UnitOfWork uow = getSession().acquireUnitOfWork();
   holders = uow.readAllObjects(DirectAggregateMapHolder.class, holderExp);
   changedHolder = (DirectAggregateMapHolder) holders.get(0);
   changedHolder.removeDirectToAggregateMapItem(new Integer(1));
   AggregateMapValue mapValue = new AggregateMapValue();
   mapValue.setValue(3);
   changedHolder.addDirectToAggregateMapItem(new Integer(3), mapValue);
   uow.commit();
   Object holderForComparison = uow.readObject(changedHolder);
   if (!compareObjects(changedHolder, holderForComparison)) {
     throw new TestErrorException("Objects do not match after write");
   }
 }