* point, Finalizer can stop running
     */
    if (!finalizableReferenceClass.getName().equals(FINALIZABLE_REFERENCE)) {
      throw new IllegalArgumentException("Expected " + FINALIZABLE_REFERENCE + ".");
    }

    Finalizer finalizer = new Finalizer(finalizableReferenceClass, queue, frqReference);
    String threadName = Finalizer.class.getName();
    Thread thread = null;

  @Test
  public void testGetFinalizerUrl() {
    assertThat(getClass().getResource("internal/Finalizer.class")).isNotNull();
  }

  @Test
  public void testFinalizeClassHasNoNestedClasses() throws Exception {
    // Ensure that the Finalizer class has no nested classes.
    // See https://github.com/google/guava/issues/1505
    assertThat(Finalizer.class.getDeclaredClasses()).isEmpty();
  }

  @Test
  public void testGetFinalizerUrl() {
    assertThat(getClass().getResource("internal/Finalizer.class")).isNotNull();
  }

  @Test
  public void testFinalizeClassHasNoNestedClasses() throws Exception {
    // Ensure that the Finalizer class has no nested classes.
    // See https://github.com/google/guava/issues/1505
    assertThat(Finalizer.class.getDeclaredClasses()).isEmpty();
  }

# FinalizableReferenceQueue is unused.
-keepnames class com.google.common.base.internal.Finalizer {
  *** startFinalizer(...);
}
# However, it cannot "spot" that this method needs to be kept IF the class is.
-keepclassmembers class com.google.common.base.internal.Finalizer {
  *** startFinalizer(...);
}
-keepnames class com.google.common.base.FinalizableReference {
  void finalizeReferent();
}

  public void testAwait_countDownLatch() {
    CountDownLatch latch = new CountDownLatch(1);
    Object unused =
        new Object() {
          @SuppressWarnings({"removal", "Finalize"}) // b/260137033
          @Override
          protected void finalize() {
            latch.countDown();
          }
        };
    unused = null; // Hint to the JIT that unused is unreachable
    GcFinalization.await(latch);

  public void testAwait_countDownLatch() {
    CountDownLatch latch = new CountDownLatch(1);
    Object unused =
        new Object() {
          @SuppressWarnings({"removal", "Finalize"}) // b/260137033
          @Override
          protected void finalize() {
            latch.countDown();
          }
        };
    unused = null; // Hint to the JIT that unused is unreachable
    GcFinalization.await(latch);

    implements FinalizableReference {
  /**
   * Constructs a new finalizable weak reference.
   *
   * @param referent to weakly reference
   * @param queue that should finalize the referent
   */
  protected FinalizableWeakReference(@Nullable T referent, FinalizableReferenceQueue queue) {
    super(referent, queue.queue);
    queue.cleanUp();
  }

    implements FinalizableReference {
  /**
   * Constructs a new finalizable weak reference.
   *
   * @param referent to weakly reference
   * @param queue that should finalize the referent
   */
  protected FinalizableWeakReference(@Nullable T referent, FinalizableReferenceQueue queue) {
    super(referent, queue.queue);
    queue.cleanUp();
  }

    implements FinalizableReference {
  /**
   * Constructs a new finalizable soft reference.
   *
   * @param referent to softly reference
   * @param queue that should finalize the referent
   */
  protected FinalizableSoftReference(@Nullable T referent, FinalizableReferenceQueue queue) {
    super(referent, queue.queue);
    queue.cleanUp();
  }

    write(out, data, 0, 100, true);
    File file = out.getFile();
    assertEquals(100, file.length());
    assertTrue(file.exists());
    out.close();

    // Make sure that finalize deletes the file
    out = null;

    // times out and throws RuntimeException on failure
    GcFinalization.awaitDone(
        new GcFinalization.FinalizationPredicate() {
          @Override