@Override
    public final boolean cancel(boolean mayInterruptIfRunning) {
      return super.cancel(mayInterruptIfRunning);
    }
  }

  private static final Logger log = Logger.getLogger(AbstractFuture.class.getName());

  private State state;
  private V value;
  private @Nullable Future<? extends V> delegate;
  private @Nullable Throwable throwable;
  private boolean mayInterruptIfRunning;
  private List<Listener> listeners;

    // TODO(cpovirk): Presize to something plausible?
    StringBuilder builder = new StringBuilder();
    if (getClass().getName().startsWith("com.google.common.util.concurrent.")) {
      builder.append(getClass().getSimpleName());
    } else {
      builder.append(getClass().getName());
    }
    builder.append('@').append(toHexString(identityHashCode(this))).append("[status=");
    if (isCancelled()) {