@Override
    public Thread newThread(Runnable r) {
      return new Thread(r);
    }
  }

  public interface TrackedRunnable extends Runnable {
    boolean isDone();
  }

  public static TrackedRunnable trackedRunnable(long timeoutMillis) {
    return new TrackedRunnable() {
      private volatile boolean done = false;

      @Override
      public boolean isDone() {
        return done;