Object copy = reserialize(object);
    assertEquals(object, copy);
    assertEquals(object.getClass(), copy.getClass());
  }

  @J2ktIncompatible
  @GwtIncompatible // serialization
  private static Object reserialize(Object object) throws Exception {
    ByteArrayOutputStream bytes = new ByteArrayOutputStream();
    new ObjectOutputStream(bytes).writeObject(object);

                  @Override
                  public ListenableFuture<Class<?>> apply(Throwable input) {
                    return Futures.<Class<?>>immediateFuture(input.getClass());
                  }
                },
                directExecutor());
    assertThat(f.get()).isEqualTo(CustomRuntimeException.class);
  }

  public void testTransform() throws Exception {
    FluentFuture<Integer> f =

    future
        .getClass()
        .getMethod(
            "setFuture",
            future.getClass().getClassLoader().loadClass(ListenableFuture.class.getName()))
        .invoke(future, badFuture);
    CancellationException expected = assertThrows(CancellationException.class, () -> future.get());
    assertThat(expected).hasCauseThat().isInstanceOf(IllegalArgumentException.class);

    // Make sure we are actually running with the expected helper implementation
    Class<?> abstractFutureClass = classLoader.loadClass(AggregateFutureState.class.getName());
    Field helperField = abstractFutureClass.getDeclaredField("ATOMIC_HELPER");
    helperField.setAccessible(true);
    assertEquals(expectedHelperClassName, helperField.get(null).getClass().getSimpleName());
  }

 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public abstract class FinalizableWeakReference<T> extends WeakReference<T>
    implements FinalizableReference {
  /**

    exec.execute(task);
    runLatch.await();
    taskLatch.countDown();

    ExecutionException e =
        assertThrows(ExecutionException.class, () -> task.get(5, TimeUnit.SECONDS));
    assertEquals(IllegalStateException.class, e.getCause().getClass());

    assertTrue(listenerLatch.await(5, TimeUnit.SECONDS));
    assertTrue(task.isDone());
    assertFalse(task.isCancelled());
  }

  }

  private static final class ThrowingTearDown implements TearDown {

    private final String id;
    boolean ran = false;

    ThrowingTearDown(String id) {
      this.id = id;
    }

    @Override
    public void tearDown() throws Exception {
      ran = true;
      throw new RuntimeException(id);
    }
  }

  private static final class SimpleTearDown implements TearDown {

    ListenableFuture<String> chain = buildChainingFuture(badInput);
    ExecutionException e = assertThrows(ExecutionException.class, () -> chain.get());
    assertSame(RuntimeException.class, e.getCause().getClass());
  }

  /** Proxy to throw a {@link RuntimeException} out of the {@link #get()} method. */
  public static class BadFuture extends SimpleForwardingListenableFuture<Integer> {
    protected BadFuture(ListenableFuture<Integer> delegate) {

    assertThat(Enums.getIfPresent(TestEnum.class, "CHEETO")).isPresent();
    assertThat(Enums.getIfPresent(TestEnum.class, "HONDA")).isPresent();
    assertThat(Enums.getIfPresent(TestEnum.class, "POODLE")).isPresent();

    assertThat(Enums.getIfPresent(TestEnum.class, "CHEETO")).hasValue(TestEnum.CHEETO);
    assertThat(Enums.getIfPresent(TestEnum.class, "HONDA")).hasValue(TestEnum.HONDA);

    future
        .getClass()
        .getMethod(
            "setFuture",
            future.getClass().getClassLoader().loadClass(ListenableFuture.class.getName()))
        .invoke(future, badFuture);
    CancellationException expected = assertThrows(CancellationException.class, () -> future.get());
    assertThat(expected).hasCauseThat().isInstanceOf(IllegalArgumentException.class);