code: public void registerFlushDelay (Class<?> objclass, long delay)
      {
          ClientDObjectMgr omgr = (ClientDObjectMgr)getDObjectManager();
          omgr.registerFlushDelay(objclass, delay);
      }
docs: Instructs the distributed object manager associated with this client to allow objects of the
  specified class to linger around the specified number of milliseconds after their last
  subscriber has been removed before the client finally removes its object proxy and flushes
  the object. Normally, objects are flushed immediately following the removal of their last
  subscriber.
  
  <p><em>Note:</em> the delay will be applied to derived classes as well as exact
  matches. <em>Note also:</em> this method cannot be called until after the client has
  established a connection with the server and the distributed object manager is available.