code: protected void notifyObservers (int level)
      {
          final int warningsLeft = getWarnings().length - level - 1;
          final long msLeft = _nextReboot - System.currentTimeMillis();
          _observers.apply(new ObserverList.ObserverOp<PendingShutdownObserver>() {
              public boolean apply (PendingShutdownObserver observer) {
                  observer.shutdownPlanned(warningsLeft, msLeft);
                  return true;
              }
          });
      }
docs: Notify all PendingShutdownObservers of the pending shutdown!