docs: @SuppressWarnings("deprecation")
      private final void cancel() {
          /**
           * first kill async http worker; before suicide LESSON: MUST KILL AND
           * WAIT FOR CHILDREN to reply back before kill itself.
           */
          cancelCancellable();
          if (asyncWorker != null && asyncWorker.isTerminated()) {
              asyncWorker.tell(RequestWorkerMsgType.CANCEL, getSelf());
  
          } else {
              logger.info("asyncWorker has not been initilized (null). "
                      + "Will not tell it cancel");
              // in case this is the 1st request. currently only manager can send
              // this.
              if (sender == null)
                  sender = getSender();
              replyErrors(PcConstants.REQUEST_CANCELED,
                      PcConstants.REQUEST_CANCELED, PcConstants.NA,
                      PcConstants.NA_INT);
          }
  
      }