code: public void purge( MessageSelector selector ) throws JMSException
      {
          if (volatileStore != null)
              purgeStore(volatileStore,selector);
          if (persistentStore != null)
          {
          	openTransaction();
          	try
          	{
          		purgeStore(persistentStore,selector);
          		commitChanges();
          	}
          	finally
          	{
          		closeTransaction();
          	}
          }
      }
docs: Purge some messages from the buffer