class PersistentSet implements Set<E> {

    @Override
    public boolean containsAll(Collection<?> c) {
        checkNotNull(c, "Collection cannot be internal.");
        for (Object item : c) {
            if (!items.contains(serializer.encode(item))) {
                return false;
            }
        }
        return true;
    }

    public  PersistentSet(org.onosproject.store.service.Serializer serializer, DB database, String name);

}