code: public void     rebuild() throws Exception
      {
          Preconditions.checkState(state.get() == State.STARTED, "Not started");
  
          internalRebuild();
  
          reset();
      }
docs: NOTE: this is a BLOCKING method. Completely rebuild the internal cache by querying
  for all needed data WITHOUT generating any events to send to listeners.
  
  @throws Exception errors