checkNotNull(unit);
    return get();
  }

  @Override
  public boolean isCancelled() {
    return false;
  }

  @Override
  public boolean isDone() {
    return true;
  }

  @Override
  public String toString() {
    // Behaviour analogous to AbstractFuture#toString().
    return super.toString() + "[status=SUCCESS, result=[" + value + "]]";
  }

    final MockReference reference = new MockReference(frq = new FinalizableReferenceQueue());

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

  static class MockReference extends FinalizableWeakReference<Object> {

    volatile boolean finalizeReferentCalled;

    final MockReference reference = new MockReference(frq = new FinalizableReferenceQueue());

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

  static class MockReference extends FinalizableWeakReference<Object> {

    volatile boolean finalizeReferentCalled;

/**
 * A {@link Future} that accepts completion listeners. Each listener has an associated executor, and
 * it is invoked using this executor once the future's computation is {@linkplain Future#isDone()
 * complete}. If the computation has already completed when the listener is added, the listener will
 * execute immediately.
 *
 * <p>See the Guava User Guide article on <a

        throws InterruptedException, ExecutionException, TimeoutException {
      return super.get(timeout, unit);
    }

    @Override
    public final boolean isDone() {
      return super.isDone();
    }

    @Override
    public final boolean isCancelled() {
      return super.isCancelled();
    }

    @Override

       * important for other reasons: run() can still be invoked concurrently in different threads,
       * even with the above null checks.)
       */
      timeoutFutureRef = null;
      if (delegate.isDone()) {
        timeoutFuture.setFuture(delegate);
      } else {
        try {
          ScheduledFuture<?> timer = timeoutFuture.timer;

 * previous callable has returned -- and, if the previous callable was an {@link AsyncCallable}, not
 * until the {@code Future} it returned is {@linkplain Future#isDone done} (successful, failed, or
 * cancelled).
 *
 * <p>This class serializes execution of <i>submitted</i> tasks but not any <i>listeners</i> of
 * those tasks.
 *

                  }
                }),
            executor);
    ListenableFuture<?> statusFuture = closingFuture.statusFuture();
    waiter.awaitStarted();
    assertThat(statusFuture.isDone()).isFalse();
    waiter.awaitReturned();
    assertThat(getUninterruptibly(statusFuture)).isNull();
  }

  public void testStatusFuture_failure() throws Exception {
    ClosingFuture<String> closingFuture =

                  }
                }),
            executor);
    ListenableFuture<?> statusFuture = closingFuture.statusFuture();
    waiter.awaitStarted();
    assertThat(statusFuture.isDone()).isFalse();
    waiter.awaitReturned();
    assertThat(getUninterruptibly(statusFuture)).isNull();
  }

  public void testStatusFuture_failure() throws Exception {
    ClosingFuture<String> closingFuture =

        }
      };

  public void testServiceStartStop() throws Exception {
    NullService service = new NullService();
    service.startAsync().awaitRunning();
    assertFalse(future.isDone());
    service.stopAsync().awaitTerminated();
    assertTrue(future.isCancelled());
  }

  private class NullService extends AbstractScheduledService {
    @Override