import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A TimeLimiter implementation which actually does not attempt to limit time at all. This may be
 * desirable to use in some unit tests. More importantly, attempting to debug a call which is
 * time-limited would be extremely annoying, so this gives you a time-limiter you can easily swap in

 * be clearly documented.
 *
 * <p>Note that although your APIs should be liberal in what they accept, your methods which
 * <i>return</i> iterables should make every attempt to return ones of the robust variety.
 *
 * <p>This testing utility is not thread-safe.
 *
 * @author Kevin Bourrillion
 */
@GwtCompatible

   *
   * <p>The returned {@code Future} attempts to keep its cancellation state in sync with that of the
   * input future and that of the future returned by the chain function. That is, if the returned
   * {@code Future} is cancelled, it will attempt to cancel the other two, and if either of the
   * other two is cancelled, the returned {@code Future} will receive a callback in which it will
   * attempt to cancel itself.
   *

        queue.add(task);
        return;
      }

      oldRunCount = workerRunCount;

      // If the worker is not yet running, the delegate Executor might reject our attempt to start
      // it. To preserve FIFO order and failure atomicity of rejected execution when the same
      // Runnable is executed more than once, allocate a wrapper that we know is safe to remove by
      // object identity.

   * for {@code asMapOfRanges().iterator().remove()}.
   *
   * <p>The returned range map will throw an {@link IllegalArgumentException} on an attempt to
   * insert a range not {@linkplain Range#encloses(Range) enclosed} by {@code range}.
   */
  // TODO(cpovirk): Consider documenting that IAE on the various methods that can throw it.

 *       will be thrown.
 *   <li>If no exceptions or errors were thrown in the try block, the <i>first</i> exception thrown
 *       by an attempt to close a resource will be thrown.
 *   <li>Any exception caught when attempting to close a resource that is <i>not</i> thrown (because
 *       another exception is already being thrown) is <i>suppressed</i>.
 * </ul>
 *

  @Override
  public boolean isCancelled() {
    final Object localValue = value;
    return localValue instanceof Cancellation;
  }

  /**
   * {@inheritDoc}
   *
   * <p>If a cancellation attempt succeeds on a {@code Future} that had previously been {@linkplain
   * #setFuture set asynchronously}, then the cancellation will also be propagated to the delegate
   * {@code Future} that was supplied in the {@code setFuture} call.

   *
   * <p>The returned view supports all optional operations supported by this {@code RangeSet}, with
   * the caveat that an {@link IllegalArgumentException} is thrown on an attempt to {@linkplain
   * #add(Range) add} any range not {@linkplain Range#encloses(Range) enclosed} by {@code view}.
   */
  RangeSet<C> subRangeSet(Range<C> view);

  // Modification

  /**

    PeekingIterator<?> peekingIterator = Iterators.peekingIterator(iterator);

    assertEquals("A", peekingIterator.next());
    assertEquals("B", peekingIterator.peek());

    /* Should complain on attempt to remove() after peek(). */
    try {
      peekingIterator.remove();
      fail("remove() should throw IllegalStateException after a peek()");
    } catch (IllegalStateException e) {
      /* expected */
    }

      acquiredLockList.add(node);
    }
  }

  /**
   * CycleDetectingLock implementations must call this method in a {@code finally} clause after any
   * attempt to change the lock state, including both lock and unlock attempts. Failure to do so can
   * result in corrupting the acquireLocks set.
   */
  private static void lockStateChanged(CycleDetectingLock lock) {
    if (!lock.isAcquiredByCurrentThread()) {