assertFalse(sleeper.completed);
    assertTrue(getUninterruptibly(delayedFuture));

    assertTrue(Thread.interrupted()); // clears the interrupt state, too
    assertTrue(sleeper.completed);
  }

  private static class SleepingRunnable implements Runnable {
    final int millis;
    volatile boolean completed;

    public SleepingRunnable(int millis) {

    assertSame(defaultThread.getThreadGroup(), thread.getThreadGroup());
    assertSame(defaultThread.getUncaughtExceptionHandler(), thread.getUncaughtExceptionHandler());

    assertFalse(completed);
    thread.start();
    thread.join();
    assertTrue(completed);

    // Creating a new thread from the same ThreadFactory will have the same
    // pool ID but a thread ID of 2.
    Thread thread2 = threadFactory.newThread(monitoredRunnable);

    assertFalse(sleeper.completed);
    assertTrue(getUninterruptibly(delayedFuture));

    assertTrue(Thread.interrupted()); // clears the interrupt state, too
    assertTrue(sleeper.completed);
  }

  private static class SleepingRunnable implements Runnable {
    final int millis;
    volatile boolean completed;

    public SleepingRunnable(int millis) {

 */
public final class InternalFutures {
  /**
   * Usually returns {@code null} but, if the given {@code Future} has failed, may <i>optionally</i>
   * return the cause of the failure. "Failure" means specifically "completed with an exception"; it
   * does not include "was cancelled." To be explicit: If this method returns a non-null value,
   * then:
   *
   * <ul>
   *   <li>{@code isDone()} must return {@code true}

   *
   * <p>Caches loaded by a {@link CacheLoader} will call {@link CacheLoader#load} to load new values
   * into the cache. Newly loaded values are added to the cache using {@code
   * Cache.asMap().putIfAbsent} after loading has completed; if another value was associated with
   * {@code key} while the new value was loading then a removal notification will be sent for the
   * new value.
   *

    assertSame(defaultThread.getThreadGroup(), thread.getThreadGroup());
    assertSame(defaultThread.getUncaughtExceptionHandler(), thread.getUncaughtExceptionHandler());

    assertFalse(completed);
    thread.start();
    thread.join();
    assertTrue(completed);

    // Creating a new thread from the same ThreadFactory will have the same
    // pool ID but a thread ID of 2.
    Thread thread2 = threadFactory.newThread(monitoredRunnable);

  protected InternalFutureFailureAccess() {}

  /**
   * Usually returns {@code null} but, if this {@code Future} has failed, may <i>optionally</i>
   * return the cause of the failure. "Failure" means specifically "completed with an exception"; it
   * does not include "was cancelled." To be explicit: If this method returns a non-null value,
   * then:
   *
   * <ul>
   *   <li>{@code isDone()} must return {@code true}

   *
   * <p>Caches loaded by a {@link CacheLoader} will call {@link CacheLoader#load} to load new values
   * into the cache. Newly loaded values are added to the cache using {@code
   * Cache.asMap().putIfAbsent} after loading has completed; if another value was associated with
   * {@code key} while the new value was loading then a removal notification will be sent for the
   * new value.
   *

abstract class AggregateFutureState<OutputT extends @Nullable Object>
    extends AbstractFuture.TrustedFuture<OutputT> {
  // Lazily initialized the first time we see an exception; not released until all the input futures
  // have completed and we have processed them all.
  @CheckForNull private volatile Set<Throwable> seenExceptions = null;

  private volatile int remaining;

  private static final AtomicHelper ATOMIC_HELPER;

 * it is invoked using this executor once the future's computation is {@linkplain Future#isDone()
 * complete}. If the computation has already completed when the listener is added, the listener will
 * execute immediately.
 *
 * <p>See the Guava User Guide article on <a
 * href="https://github.com/google/guava/wiki/ListenableFutureExplained">{@code
 * ListenableFuture}</a>.