};
      }
    },
    OLD_ABSTRACT_FUTURE {
      @Override
      ExecutionListWrapper newExecutionList() {
        return new ExecutionListWrapper() {
          final OldAbstractFuture<Object> future = new OldAbstractFuture<Object>() {};

          @Override
          public void add(Runnable runnable, Executor executor) {
            future.addListener(runnable, executor);
          }

          @Override