code: private void preSave(MembershipType type, boolean isNew) throws Exception
     {
        for (MembershipTypeEventListener listener : listeners)
        {
           listener.preSave(type, isNew);
        }
     }
docs: Notifying listeners before membership type creation.
  
  @param type
  the membership which is used in create operation
  @param isNew
  true, if we have a deal with new membership type, otherwise it is false
  which mean update operation is in progress
  @throws Exception
  if any listener failed to handle the event