}

  @SuppressWarnings("Java8ApiChecker")
  static class MyServerExampleWithCleaner implements AutoCloseable {
    private static final Cleaner cleaner = Cleaner.create();

    private static Runnable closeServerSocketRunnable(
        ServerSocket serverSocket, AtomicBoolean cleanerRan) {
      return () -> {
        try {
          serverSocket.close();
          cleanerRan.set(true);

   * 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 should
   * return promptly.
   *
   * <p>The default implementation returns a new {@link Executor} that sets the name of its threads

    assertTrue(ArbitraryInstances.get(ConcurrentMap.class).isEmpty());
    assertTrue(ArbitraryInstances.get(ConcurrentNavigableMap.class).isEmpty());
    ArbitraryInstances.get(Executor.class).execute(ArbitraryInstances.get(Runnable.class));
    assertThat(ArbitraryInstances.get(ThreadFactory.class)).isNotNull();
    assertFreshInstanceReturned(
        BlockingQueue.class,
        BlockingDeque.class,
        PriorityBlockingQueue.class,

            Thread webFsCrawlerThread = null;
            Thread dataCrawlerThread = null;

            if (runAll || webConfigIdList != null || fileConfigIdList != null) {
                webFsCrawlerThread = new Thread((Runnable) () -> {
                    // crawl web
                    writeTimeToSessionInfo(crawlingInfoHelper, Constants.WEB_FS_CRAWLER_START_TIME);

   * <p>This class is very similar to {@link SequentialExecutor} with the exception that events can
   * be added without necessarily executing immediately.
   */
  private static final class PerListenerQueue<L> implements Runnable {
    final L listener;
    final Executor executor;

    @GuardedBy("this")
    final Queue<ListenerCallQueue.Event<L>> waitQueue = new ArrayDeque<>();

    @GuardedBy("this")

    /** An array of supported language codes. */
    protected String[] supportedLanguages;

    /** A list of shutdown hooks to be executed on system shutdown. */
    protected List<Runnable> shutdownHookList = new ArrayList<>();

    /** The previous state of the cluster. */
    protected AtomicInteger previousClusterState = new AtomicInteger(0);

    /** The version of the Fess application. */

#### Do-stuff-later pool

Sometimes there's an action required like calling the application layer or responding to a ping, and the thread discovering the action is not the thread that should do the work. We enqueue a runnable on this executor and it gets handled by one of the executor's threads.

### Locks

We have 3 different things that we synchronize on.

#### Http2Connection

@SuppressWarnings("ShortCircuitBoolean")
abstract class AbstractTransformFuture<
        I extends @Nullable Object, O extends @Nullable Object, F, T extends @Nullable Object>
    extends FluentFuture.TrustedFuture<O> implements Runnable {
  static <I extends @Nullable Object, O extends @Nullable Object> ListenableFuture<O> createAsync(
      ListenableFuture<I> input,
      AsyncFunction<? super I, ? extends O> function,
      Executor executor) {

import java.util.HashMap;
import java.util.StringTokenizer;

import jcifs.smb1.Config;
import jcifs.smb1.util.Hexdump;
import jcifs.smb1.util.LogStream;

class NameServiceClient implements Runnable {

    static final int DEFAULT_SO_TIMEOUT = 5000;
    static final int DEFAULT_RCV_BUF_SIZE = 576;
    static final int DEFAULT_SND_BUF_SIZE = 576;
    static final int NAME_SERVICE_UDP_PORT = 137;

        final Set<Exception> exceptions = new HashSet<>();

        Thread[] threads = new Thread[threadCount];
        for (int i = 0; i < threadCount; i++) {
            threads[i] = new Thread(new Runnable() {
                @Override
                public void run() {
                    try {
                        for (int j = 0; j < iterationsPerThread; j++) {
                            // Access enum values