notifyFailed(EXCEPTION);
    }

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

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

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

      notifyFailed(EXCEPTION);
    }

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

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

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

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

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

  /*
   * A NoOp service that will delay the startup and shutdown notification for a configurable amount
   * of time.
   */

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

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

  /*
   * A NoOp service that will delay the startup and shutdown notification for a configurable amount
   * of time.
   */

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

              }
            } finally {
              lock.unlock();
            }
          });
    }

    @Override
    protected final void doStop() {
      // Both requireNonNull calls are safe because doStop can run only after a successful doStart.
      requireNonNull(runningTask);
      requireNonNull(executorService);
      runningTask.cancel(false);
      executorService.execute(

   */
  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 {}