}

  private static class FailStartService extends NoOpService {
    @Override
    protected void doStart() {
      notifyFailed(new IllegalStateException("start failure"));
    }
  }

  private static class FailRunService extends NoOpService {
    @Override
    protected void doStart() {
      super.doStart();
      notifyFailed(new IllegalStateException("run failure"));
    }
  }

    @Override
    protected void doStart() {
      notifyFailed(EXCEPTION);
    }

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

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

    @Override

    @Override
    protected void doStart() {
      notifyFailed(EXCEPTION);
    }

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

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

    @Override

  }

  private static class FailStartService extends NoOpService {
    @Override
    protected void doStart() {
      notifyFailed(new IllegalStateException("start failure"));
    }
  }

  private static class FailRunService extends NoOpService {
    @Override
    protected void doStart() {
      super.doStart();
      notifyFailed(new IllegalStateException("run failure"));
    }
  }

import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import org.jspecify.annotations.Nullable;

/**
 * Base class for implementing services that can handle {@link #doStart} and {@link #doStop}
 * requests, responding to them with {@link #notifyStarted()} and {@link #notifyStopped()}
 * callbacks. Its subclasses must manage threads manually; consider {@link

   * logging statements.
   */
  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. */