/**
 * 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. */

        runnables.poll().execute();
      }
    }

    private static class RunnableExecutorPair {
      final Runnable runnable;
      final Executor executor;

      RunnableExecutorPair(Runnable runnable, Executor executor) {
        this.runnable = runnable;
        this.executor = executor;
      }

      void execute() {
        try {
          executor.execute(runnable);

  }

  public void testExceptionsCaught() {
    list.add(THROWING_RUNNABLE, directExecutor());
    list.execute();
    list.add(THROWING_RUNNABLE, directExecutor());
  }

  public void testNulls() {
    new NullPointerTester().testAllPublicInstanceMethods(new ExecutionList());
  }

  private static final Runnable THROWING_RUNNABLE =
      new Runnable() {
        @Override
        public void run() {

    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

  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;

   * @throws UncheckedExecutionException if {@code runnable} throws a {@code RuntimeException}
   * @throws ExecutionError if {@code runnable} throws an {@code Error}
   * @since 22.0
   */
  void runWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit)
      throws TimeoutException, InterruptedException;

  /**
   * Invokes a specified Runnable, timing out after the specified time limit. If the target method

  }

  @Override
  @SuppressWarnings("CatchingUnchecked") // sneaky checked exception
  public void runWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit) {
    checkNotNull(runnable);
    checkNotNull(timeoutUnit);
    try {
      runnable.run();
    } catch (Exception e) { // sneaky checked exception
      throw new UncheckedExecutionException(e);
    } catch (Error e) {

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

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

    RunnableExecutorPair(

    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 {

    }
  }

  @Override
  public void runWithTimeout(Runnable runnable, long timeoutDuration, TimeUnit timeoutUnit)
      throws TimeoutException, InterruptedException {
    checkNotNull(runnable);
    checkNotNull(timeoutUnit);
    checkPositiveTimeout(timeoutDuration);

    Future<?> future = executor.submit(runnable);

    try {
      future.get(timeoutDuration, timeoutUnit);