class ReadyServiceImpl implements ReadyService {

    @Override
    public void unregisterTracker(ReadyTracker readyTracker) {
        rwlTrackers.writeLock().lock();
        try {
            if (trackers.containsKey(readyTracker)) {
                notifyTracker(readyTracker, marker -> readyTracker.onReadyMarkerRemoved(marker));
            }
            trackers.remove(readyTracker);
        } finally {
            rwlTrackers.writeLock().unlock();
        }
    }

}