code: public void removePrefetchingListeners()
      {
          if (prefetchingListeners != null)
          {
              for (Iterator it = prefetchingListeners.iterator(); it.hasNext(); )
              {
                  PBPrefetchingListener listener = (PBPrefetchingListener) it.next();
                  listener.removeThisListener();
              }
              prefetchingListeners.clear();
          }
      }
docs: remove all prefetching listeners