}
  }

  public static class FrqUser implements Callable<WeakReference<Object>> {
    public static FinalizableReferenceQueue frq = new FinalizableReferenceQueue();
    public static final Semaphore finalized = new Semaphore(0);

    @Override
    public WeakReference<Object> call() {
      WeakReference<Object> wr =
          new FinalizableWeakReference<Object>(new Integer(23), frq) {
            @Override

    }
  }

  public static class FrqUser implements Callable<WeakReference<Object>> {
    public static FinalizableReferenceQueue frq = new FinalizableReferenceQueue();
    public static final Semaphore finalized = new Semaphore(0);

    @Override
    public WeakReference<Object> call() {
      WeakReference<Object> wr =
          new FinalizableWeakReference<Object>(new Integer(23), frq) {
            @Override