AtomicReference<ScheduledExecutorService> executor = Atomics.newReference();
    AbstractScheduledService service =
        new AbstractScheduledService() {
          @Override
          protected void runOneIteration() throws Exception {}

          @Override
          protected ScheduledExecutorService executor() {
            executor.set(super.executor());
            return executor.get();
          }

    AtomicReference<ScheduledExecutorService> executor = Atomics.newReference();
    AbstractScheduledService service =
        new AbstractScheduledService() {
          @Override
          protected void runOneIteration() throws Exception {}

          @Override
          protected ScheduledExecutorService executor() {
            executor.set(super.executor());
            return executor.get();
          }

@GwtIncompatible
@J2ktIncompatible
public class ExecutionSequencerTest extends TestCase {

  ExecutorService executor;

  private ExecutionSequencer serializer;
  private SettableFuture<@Nullable Void> firstFuture;
  private TestCallable firstCallable;

  @Override
  public void setUp() throws Exception {
    executor = newCachedThreadPool();
    serializer = ExecutionSequencer.create();
    firstFuture = SettableFuture.create();

                  + runnable
                  + " with executor "
                  + executor,
              e);
    }
  }

  private static final class RunnableExecutorPair {
    final Runnable runnable;
    final Executor executor;
    @Nullable RunnableExecutorPair next;

    RunnableExecutorPair(
        Runnable runnable, Executor executor, @Nullable RunnableExecutorPair next) {

    SettableFuture<?> future = SettableFuture.create();
    Executor delegate =
        new Executor() {
          @Override
          public void execute(Runnable task) {
            if (future.set(null)) {
              awaitUninterruptibly(latch);
            }
            throw new RejectedExecutionException();
          }
        };
    SequentialExecutor executor = new SequentialExecutor(delegate);

        public Cancellable schedule(
            AbstractService service, ScheduledExecutorService executor, Runnable task) {
          return new FutureAsCancellable(
              executor.scheduleAtFixedRate(task, initialDelay, period, unit));
        }
      };
    }

    /** Schedules the task to run on the provided executor on behalf of the service. */
    abstract Cancellable schedule(

import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.ExecutorService;
import org.jspecify.annotations.NullUnmarked;

/**
 * Tests for {@link ClosingFuture} that exercise {@link
 * ClosingFuture#finishToValueAndCloser(ValueAndCloserConsumer, Executor)}.
 */
@NullUnmarked
@GwtIncompatible
@J2ktIncompatible

    ClosingFuture<String> closingFuture =
        ClosingFuture.from(executor.submit(Callables.returning(closeable1)))
            .transform(
                (DeferredCloser closer, TestCloseable v) -> {
                  assertThat(v).isSameInstanceAs(closeable1);
                  return "value";
                },
                executor);
    assertThat(getFinalValue(closingFuture)).isEqualTo("value");

  /* use AbstractService for state management */
  private final Service delegate =
      new AbstractService() {
        @Override
        protected final void doStart() {
          Executor executor = renamingDecorator(executor(), () -> serviceName());
          executor.execute(
              () -> {
                try {
                  startUp();
                  notifyStarted();

@GwtIncompatible
@J2ktIncompatible
public class ExecutionSequencerTest extends TestCase {

  ExecutorService executor;

  private ExecutionSequencer serializer;
  private SettableFuture<@Nullable Void> firstFuture;
  private TestCallable firstCallable;

  @Override
  public void setUp() throws Exception {
    executor = newCachedThreadPool();
    serializer = ExecutionSequencer.create();
    firstFuture = SettableFuture.create();