abstract Cancellable schedule(
        AbstractService service, ScheduledExecutorService executor, Runnable runnable);

    private Scheduler() {}
  }

  /* use AbstractService for state management */
  private final AbstractService delegate = new ServiceDelegate();

  @WeakOuter
  private final class ServiceDelegate extends AbstractService {

 * methods. This class uses a single thread to execute the service; consider {@link AbstractService}
 * if you would like to manage any threading manually.
 *
 * @author Jesse Wilson
 * @since 1.0
 */
@GwtIncompatible
@J2ktIncompatible
@ElementTypesAreNonnullByDefault
public abstract class AbstractExecutionThreadService implements Service {
  /* use AbstractService for state management */
  private final Service delegate =

/**
 * Tests for {@link ServiceManager}.
 *
 * @author Luke Sandberg
 * @author Chris Nokleberg
 */
public class ServiceManagerTest extends TestCase {

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

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

  /*

   * it is excluded from {@link #servicesByState}, {@link #startupTimes}, {@link #toString} and all
   * logging statements.
   */
  private static final class NoOpService extends AbstractService {
    @Override
    protected void doStart() {
      notifyStarted();
    }

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

   * it is excluded from {@link #servicesByState}, {@link #startupTimes}, {@link #toString} and all
   * logging statements.
   */
  private static final class NoOpService extends AbstractService {
    @Override
    protected void doStart() {
      notifyStarted();
    }

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