public List<TravelTrip> findAll(){
        CriteriaBuilder cb = em.getCriteriaBuilder();
        CriteriaQuery<TravelTrip> criteria = cb.createQuery(TravelTrip.class);
        Root<TravelTrip> travelTrip = criteria.from(TravelTrip.class);
 
        criteria.select(travelTrip).orderBy(cb.asc(travelTrip.get("country")));
        return em.createQuery(criteria).getResultList();
    }