class AbstractSubscriptions implements Subscriptions<T> {

    @Override
    public SubscriptionsReader snapshot() {
        return SubscriptionsReader.of(exportTopicData(), exportSubscriberToFilter());
    }

    protected  AbstractSubscriptions(
            final Map<ActorRef, Set<String>> subscriberToTopic,
            final Map<ActorRef, Predicate<Collection<String>>> subscriberToFilter,
            final Map<String, TopicData<H>> topicToData);

}