BarChild barChild = new BarChild();
    AsyncFunction<Foo, BarChild> function =
        new AsyncFunction<Foo, BarChild>() {
          @Override
          public AbstractFuture<BarChild> apply(Foo unused) {
            AbstractFuture<BarChild> future = new AbstractFuture<BarChild>() {};
            future.set(barChild);
            return future;
          }
        };

    BarChild barChild = new BarChild();
    AsyncFunction<Foo, BarChild> function =
        new AsyncFunction<Foo, BarChild>() {
          @Override
          public AbstractFuture<BarChild> apply(Foo unused) {
            AbstractFuture<BarChild> future = new AbstractFuture<BarChild>() {};
            future.set(barChild);
            return future;
          }
        };

      }
    }
  }

  static class LoadingValueReference<K, V> implements ValueReference<K, V> {
    volatile ValueReference<K, V> oldValue;

    // TODO(fry): rename get, then extend AbstractFuture instead of containing SettableFuture
    final SettableFuture<V> futureValue = SettableFuture.create();
    final Stopwatch stopwatch = Stopwatch.createUnstarted();

    public LoadingValueReference() {

      }
    }
  }

  static class LoadingValueReference<K, V> implements ValueReference<K, V> {
    volatile ValueReference<K, V> oldValue;

    // TODO(fry): rename get, then extend AbstractFuture instead of containing SettableFuture
    final SettableFuture<V> futureValue = SettableFuture.create();
    final Stopwatch stopwatch = Stopwatch.createUnstarted();

    public LoadingValueReference() {