class MultiReferenceCountSubscriber extends MultiOperatorProcessor<T, T> {

    @Override
    public void cancel() {
        super.cancel();
        if (done.compareAndSet(false, true)) {
            parent.cancel(connection);
        }
    }

      MultiReferenceCountSubscriber(MultiSubscriber<? super T> downstream, MultiReferenceCount<T> parent,
            ConnectableMultiConnection connection);

}