assertThat(exceptions).isEmpty();
  }

  private static List<Throwable> runThreadsAndReturnExceptions(int numThreads, Runnable task) {
    List<Thread> threads = new ArrayList<>(numThreads);
    final List<Throwable> exceptions = new ArrayList<>(numThreads);
    for (int i = 0; i < numThreads; i++) {
      Thread thread = new Thread(task);
      thread.setUncaughtExceptionHandler(

 * <pre>{@code
 * final RateLimiter rateLimiter = RateLimiter.create(2.0); // rate is "2 permits per second"
 * void submitTasks(List<Runnable> tasks, Executor executor) {
 *   for (Runnable task : tasks) {
 *     rateLimiter.acquire(); // may wait
 *     executor.execute(task);
 *   }
 * }
 * }</pre>
 *
 * <p>As another example, imagine that we produce a stream of data, and we want to cap it at 5kb per

 * other {@code Future}, be {@linkplain #cancel cancelled}.
 *
 * <p>{@code SettableFuture} is the recommended {@code ListenableFuture} implementation when your
 * task cannot be implemented with {@link ListeningExecutorService}, the various {@link Futures}
 * utility methods, or {@link ListenableFutureTask}. Those APIs have less opportunity for developer

    assertFailsToDecode(base64(), "Wf2!", "Unrecognized character: !");
    // This sentence just isn't base64() encoded.
    assertFailsToDecode(base64(), "let's not talk of love or chains!");
    // A 4n+1 length string is never legal base64().
    assertFailsToDecode(base64(), "12345", "Invalid input length 5");

    assertFalse(listenableFuture.isDone());

    listenableFuture.addListener(singleCallListener, directExecutor());
    /*
     * Don't shut down until the listenInPoolThread task has been accepted to
     * run. We want to see what happens when it's interrupted, not when it's
     * rejected.
     */
    submitSuccessful.await();
    executorService.shutdownNow();

    TrustedListenableFutureTask<Integer> task = TrustedListenableFutureTask.create(returning(2));
    assertFalse(task.isDone());
    task.run();
    assertTrue(task.isDone());
    assertFalse(task.isCancelled());
    assertEquals(2, getDone(task).intValue());
  }

  public void testCancelled() throws Exception {
    TrustedListenableFutureTask<Integer> task = TrustedListenableFutureTask.create(returning(2));

  public <T> ListenableFuture<T> submit(Callable<T> task) {
    Preconditions.checkNotNull(task, "task must not be null!");
    return delegate.submit(task);
  }

  @Override
  public <T> ListenableFuture<T> submit(Runnable task, T result) {
    Preconditions.checkNotNull(task, "task must not be null!");
    Preconditions.checkNotNull(result, "result must not be null!");
    return delegate.submit(task, result);
  }

  @Override

   * will not be released until that submitted task is also complete.
   *
   * <p>If a task is {@linkplain Thread#interrupt interrupted} while a task is running:
   *
   * <ol>
   *   <li>execution will not stop until the task queue is empty.
   *   <li>tasks will begin execution with the thread marked as not interrupted - any interruption
   *       applies only to the task that was running at the point of interruption.

    public <T> Future<T> submit(Callable<T> task) {
      lastMethodCalled = "submit";
      assertThat(task).isInstanceOf(WrappedCallable.class);
      return inline.submit(task);
    }

    @Override
    public Future<?> submit(Runnable task) {
      lastMethodCalled = "submit";
      assertThat(task).isInstanceOf(WrappedRunnable.class);
      return inline.submit(task);
    }

    @Override

   * identify deadlocks.
   */
  @VisibleForTesting
  static final class Blocker extends AbstractOwnableSynchronizer implements Runnable {
    private final InterruptibleTask<?> task;

    private Blocker(InterruptibleTask<?> task) {
      this.task = task;
    }

    @Override
    public void run() {}

    private void setOwner(Thread thread) {
      super.setExclusiveOwnerThread(thread);
    }