class ProductCartDao extends HibernateDao<ProductCart, String> {

   public List<Long> getProductsIdOfCart(User user)
   {
      long start = System.currentTimeMillis();
      List<Long> ret = toId(scrollCartOfUser(user, 0, -1));
      long end = System.currentTimeMillis();
      logger.info("Query getProductsIdOfCart spent " + (end - start) + "ms");
      return ret;
   }

}