class MongoDbRegionRepository implements RegionRepository {

    @Override
    public void delete(Region item) {
        Page page;

        if(item.getId() == null) {
            throw new IllegalStateException("Unidentifiable region (null id)");
        } else {
            page = getPageByRegionId(item.getId());
            removeRegion(page, item);
        }
        template.save(page);
    }

}