protected abstract void shutDown() throws Exception;

  /**
   * Returns the {@link Executor} that will be used to run this service. Subclasses may override
   * this method to use a custom {@link Executor}, which may configure its worker thread with a
   * specific name, thread group or priority. The returned executor's {@link
   * Executor#execute(Runnable) execute()} method is called when this service is started and

@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();

   * calling thread. Tasks are run to completion before a {@code Future} is returned to the caller
   * (unless the executor has been shutdown).
   *
   * <p>The returned executor is backed by the executor returned by {@link
   * MoreExecutors#newDirectExecutorService} and subject to the same constraints.
   *

        int iterations = 1000;
        ExecutorService executor = Executors.newFixedThreadPool(2);
        CountDownLatch endLatch = new CountDownLatch(2);
        AtomicInteger successCount = new AtomicInteger(0);
        List<Exception> exceptions = Collections.synchronizedList(new ArrayList<>());

        // Thread 1: Continuously adds trees
        executor.submit(() -> {
            try {

      .build()

  @After
  fun tearDown() {
    engine.shutdown()
    cacheDir.deleteRecursively()
  }

  @Test
  fun get() {
    val executor = Executors.newCachedThreadPool()

    val completableFuture = execute(engine, executor, "https://google.com/robots.txt")

    try {
      val response = completableFuture.get(10, TimeUnit.SECONDS)

      assertEquals(200, response.code)

   */
  public <T extends @Nullable Object> ListenableFuture<T> submitAsync(
      AsyncCallable<T> callable, Executor executor) {
    checkNotNull(callable);
    checkNotNull(executor);
    TaskNonReentrantExecutor taskExecutor = new TaskNonReentrantExecutor(executor, this);
    AsyncCallable<T> task =
        new AsyncCallable<T>() {
          @Override

            processor.setSearcher(new TestSearcher(100));
            processor.init();

            final ExecutorService executor = Executors.newFixedThreadPool(numThreads);
            try {
                for (int i = 0; i < numThreads; i++) {
                    final int threadId = i;
                    executor.submit(() -> {
                        try {
                            startLatch.await(); // Wait for all threads to be ready

        super.tearDown(testInfo);
    }

    @Test
    public void test_constructor() {
        // Test that constructor creates an instance
        ScriptExecutor executor = new ScriptExecutor();
        assertNotNull(executor);
        assertTrue(executor instanceof JobExecutor);
    }

    @Test
    public void test_execute_withValidScriptType() {
        // Setup test script engine

    // null only for TOMBSTONE
    final @Nullable Executor executor;

    // writes to next are made visible by subsequent CAS's on the listeners field
    @Nullable Listener next;

    Listener(Runnable task, Executor executor) {
      this.task = task;
      this.executor = executor;
    }

    Listener() {
      this.task = null;
      this.executor = null;
    }
  }

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