*/
  private static final class NoOpService extends AbstractService {
    @Override
    protected void doStart() {
      notifyStarted();
    }

    @Override
    protected void doStop() {
      notifyStopped();
    }
  }

  /** This is never thrown but only used for logging. */
  private static final class EmptyServiceManagerWarning extends Throwable {}

   */
  private static final class NoOpService extends AbstractService {
    @Override
    protected void doStart() {
      notifyStarted();
    }

    @Override
    protected void doStop() {
      notifyStopped();
    }
  }

  /** This is never thrown but only used for logging. */
  private static final class EmptyServiceManagerWarning extends Throwable {}