// instead of using an AtomicReferenceFieldUpdater. This reference stores Thread instances
// and DONE/INTERRUPTED - they have a common ancestor of Runnable.
abstract class InterruptibleTask<T extends @Nullable Object>
    extends AtomicReference<@Nullable Runnable> implements Runnable {
  static {
    // Prevent rare disastrous classloading in first call to LockSupport.park.
    // See: https://bugs.openjdk.org/browse/JDK-8074773

  private val busyQueues = mutableListOf<TaskQueue>()

  /** Queues not in [busyQueues] that have non-empty [TaskQueue.futureTasks]. */
  private val readyQueues = mutableListOf<TaskQueue>()

  private val runnable: Runnable =
    object : Runnable {
      override fun run() {
        var task: Task =
          withLock {
            runCallCount++
            awaitTaskToRun()
          } ?: return

  }

  @CanIgnoreReturnValue
  static <T extends Throwable> T assertThrows(
      Class<T> expectedThrowable, ThrowingRunnable runnable) {
    return doAssertThrows(
        expectedThrowable,
        () -> {
          runnable.run();
          return null;
        },
        /* userPassedSupplier= */ false);
  }

  private static <T extends Throwable> T doAssertThrows(

  }

  @Override
  public <T> ListenableFuture<T> submit(Runnable task, T result) {
    Preconditions.checkNotNull(task, "task must not be null!");
    Preconditions.checkNotNull(result, "result must not be null!");
    return delegate.submit(task, result);
  }

  @Override
  public ListenableFuture<?> submit(Runnable task) {
    Preconditions.checkNotNull(task, "task must not be null!");

  }

  @Override
  public <T> ListenableFuture<T> submit(Runnable task, T result) {
    Preconditions.checkNotNull(task, "task must not be null!");
    Preconditions.checkNotNull(result, "result must not be null!");
    return delegate.submit(task, result);
  }

  @Override
  public ListenableFuture<?> submit(Runnable task) {
    Preconditions.checkNotNull(task, "task must not be null!");

   * otherwise-concurrent GC cycle.
   */
  private static final class TaskNonReentrantExecutor extends AtomicReference<RunningState>
      implements Executor, Runnable {

    /**
     * Used to update and read the latestTaskQueue field. Set to null once the runnable has been run
     * or queued.
     */
    @Nullable ExecutionSequencer sequencer;

    /**

  }

  @Test fun interruptStopsThread() {
    val taskRunnerThreads = mutableListOf<Thread>()
    val taskRunner =
      TaskRunner(
        RealBackend { runnable ->
          Thread(runnable, "interruptStopsThread TaskRunner")
            .also { taskRunnerThreads += it }
        },
      )

    val pool =
      factory.newConnectionPool(
        taskRunner = taskRunner,

                public Integer call() {
                  return counter.incrementAndGet();
                }
              });
      CyclicBarrier barrier = new CyclicBarrier(numThreads + 1);
      Runnable wrapper =
          new Runnable() {
            @Override
            public void run() {
              awaitUnchecked(barrier);
              task.run();
              awaitUnchecked(barrier);
            }
          };

   */
  protected ScheduledExecutorService executor() {
    @WeakOuter
    final class ThreadFactoryImpl implements ThreadFactory {
      @Override
      public Thread newThread(Runnable runnable) {
        return MoreExecutors.newThread(serviceName(), runnable);
      }
    }
    ScheduledExecutorService executor =
        Executors.newSingleThreadScheduledExecutor(new ThreadFactoryImpl());

 * @author George van den Driessche
 */
@GwtCompatible
@NullMarked
public class AbstractTester<G> extends TestCase {
  private G subjectGenerator;
  private String suiteName;
  private @Nullable Runnable setUp;
  private @Nullable Runnable tearDown;

  // public so that it can be referenced in generated GWT tests.
  @Override
  public void setUp() throws Exception {
    if (setUp != null) {
      setUp.run();
    }
  }