}
    }

    /** Controls how long to wait for all services to reach a terminal state. */
    final Monitor.Guard stoppedGuard = new StoppedGuard();

    @WeakOuter
    final class StoppedGuard extends Monitor.Guard {
      StoppedGuard() {
        super(ServiceManagerState.this.monitor);
      }

      @Override
      @GuardedBy("ServiceManagerState.this.monitor")