/**
 * Static utility methods pertaining to the {@link Runnable} interface.
 *
 * @since 16.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public final class Runnables {

  private static final Runnable EMPTY_RUNNABLE =
      new Runnable() {
        @Override
        public void run() {}
      };

  /** Returns a {@link Runnable} instance that does nothing when run. */

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

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

    RunnableExecutorPair(

    tester.testForwarding(
        Runnable.class,
        new Function<Runnable, Runnable>() {
          @Override
          public Runnable apply(final Runnable runnable) {
            return new ForwardingRunnable(runnable);
          }
        });
  }

  public void testToStringForwarding() {
    tester.testForwarding(
        Runnable.class,
        new Function<Runnable, Runnable>() {
          @Override

    try {
      final SequentialExecutor executor = new SequentialExecutor(service);
      Runnable errorTask =
          new Runnable() {
            @Override
            public void run() {
              throw new MyError();
            }
          };
      Runnable barrierTask =
          new Runnable() {
            @Override
            public void run() {
              try {

    tester.testForwarding(
        Runnable.class,
        new Function<Runnable, Runnable>() {
          @Override
          public Runnable apply(final Runnable runnable) {
            return new ForwardingRunnable(runnable);
          }
        });
  }

  public void testToStringForwarding() {
    tester.testForwarding(
        Runnable.class,
        new Function<Runnable, Runnable>() {
          @Override

    ThrowingRunnable runnable = new ThrowingRunnable(5, ex);
    future = service.scheduleAtFixedRate(runnable, 1, 1, TimeUnit.MILLISECONDS);
    assertExecutionException(future, ex);
    assertEquals(5, runnable.count);
    assertEquals(0, delegate.getQueue().size());

    runnable = new ThrowingRunnable(5, ex);
    future = service.scheduleWithFixedDelay(runnable, 1, 1, TimeUnit.MILLISECONDS);

        }
      };
  private static final Runnable GOOD_RUNNABLE =
      new Runnable() {
        @Override
        public void run() {
          try {
            MILLISECONDS.sleep(DELAY_MS);
          } catch (InterruptedException e) {
            throw new RuntimeException(e);
          }
        }
      };
  private static final Runnable BAD_RUNNABLE =
      new Runnable() {
        @Override

    try {
      final SequentialExecutor executor = new SequentialExecutor(service);
      Runnable errorTask =
          new Runnable() {
            @Override
            public void run() {
              throw new MyError();
            }
          };
      Runnable barrierTask =
          new Runnable() {
            @Override
            public void run() {
              try {

  enum WorkerRunningState {
    /** Runnable is not running and not queued for execution */
    IDLE,
    /** Runnable is not running, but is being queued for execution */
    QUEUING,
    /** runnable has been submitted but has not yet begun execution */
    QUEUED,
    RUNNING,
  }

  /** Underlying executor that all submitted Runnable objects are run on. */
  private final Executor executor;

// 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.java.net/browse/JDK-8074773