// TODO(diamondm) consider moving this into addPendingString so it's always in the output
    if (this instanceof ScheduledFuture) {
      return "remaining delay=[" + ((ScheduledFuture) this).getDelay(MILLISECONDS) + " ms]";
    }
    return null;
  }

  @SuppressWarnings("CatchingUnchecked") // sneaky checked exception
  private void addPendingString(StringBuilder builder) {