case OPEN:
          break;
      }
      throw new AssertionError(state);
    }
    future.addListener(() -> provideValueAndCloser(consumer, ClosingFuture.this), executor);
  }

  private static <C extends @Nullable Object, V extends C> void provideValueAndCloser(
      ValueAndCloserConsumer<C> consumer, ClosingFuture<V> closingFuture) {
    consumer.accept(new ValueAndCloser<C>(closingFuture));
  }

        case OPEN:
          break;
      }
      throw new AssertionError(state);
    }
    future.addListener(() -> provideValueAndCloser(consumer, ClosingFuture.this), executor);
  }

  private static <C extends @Nullable Object, V extends C> void provideValueAndCloser(
      ValueAndCloserConsumer<C> consumer, ClosingFuture<V> closingFuture) {
    consumer.accept(new ValueAndCloser<C>(closingFuture));
  }