@Override
          protected void finalize() {
            future.set(null);
          }
        };
    unused = null; // Hint to the JIT that unused is unreachable
    GcFinalization.awaitDone(future);
    assertTrue(future.isDone());
    assertFalse(future.isCancelled());
  }

  public void testAwaitDone_future_cancel() {
    final SettableFuture<@Nullable Void> future = SettableFuture.create();

   *
   * <pre>{@code
   * awaitDone(new FinalizationPredicate() {
   *   public boolean isDone() {
   *     return ref.get() == null;
   *   }
   * });
   * }</pre>
   *
   * @throws RuntimeException if timed out or interrupted while waiting
   */
  public static void awaitClear(WeakReference<?> ref) {
    awaitDone(
        new FinalizationPredicate() {
          @Override

          @Override
          protected void finalize() {
            future.set(null);
          }
        };
    unused = null; // Hint to the JIT that unused is unreachable
    GcFinalization.awaitDone(future);
    assertTrue(future.isDone());
    assertFalse(future.isCancelled());
  }

  public void testAwaitDone_future_cancel() {
    final SettableFuture<@Nullable Void> future = SettableFuture.create();

   *
   * <pre>{@code
   * awaitDone(new FinalizationPredicate() {
   *   public boolean isDone() {
   *     return ref.get() == null;
   *   }
   * });
   * }</pre>
   *
   * @throws RuntimeException if timed out or interrupted while waiting
   */
  public static void awaitClear(WeakReference<?> ref) {
    awaitDone(
        new FinalizationPredicate() {
          @Override

    frq = null;
  }


  public void testFinalizeReferentCalled() {
    final MockReference reference = new MockReference(frq = new FinalizableReferenceQueue());

    GcFinalization.awaitDone(
        new GcFinalization.FinalizationPredicate() {
          @Override
          public boolean isDone() {
            return reference.finalizeReferentCalled;
          }
        });
  }