Ordering Results

The order of the results of a query can be set by calling the CriteriaQuery.orderBy method and passing in an Order object. Order objects are created by calling either the CriteriaBuilder.asc or the CriteriaBuilder.desc method. The asc method is used to order the results by ascending value of the passed expression parameter. The desc method is used to order the results by descending value of the passed expression parameter. The following query shows the use of the desc method:

CriteriaQuery<Pet> cq = cb.createQuery(Pet.class);
Root<Pet> pet = cq.from(Pet.class);
cq.select(pet);
cq.orderBy(cb.desc(pet.get(Pet_.birthday));

In this query, the results will be ordered by the pet’s birthday from highest to lowest. That is, pets born in December will appear before pets born in May.

The following query shows the use of the asc method:

CriteriaQuery<Pet> cq = cb.createQuery(Pet.class);
Root<Pet> pet = cq.from(Pet.class);
Join<Owner, Address> address = cq.join(Pet_.owners).join(Owner_.address);
cq.select(pet);
cq.orderBy(cb.asc(address.get(Address_.postalCode));

In this query, the results will be ordered by the pet owner’s postal code from lowest to highest. That is, pets whose owner lives in the 10001 zip code will appear before pets whose owner lives in the 91000 zip code.

If more than one Order object is passed to orderBy, the precedence is determined by the order in which they appear in the argument list of orderBy. The first Order object has precedence.

The following code orders results by multiple criteria:

CriteriaQuery<Pet> cq = cb.createQuery(Pet.class);
Root<Pet> pet = cq.from(Pet.class);
Join<Pet, Owner> owner = cq.join(Pet_.owners);
cq.select(pet);
cq.orderBy(cb.asc(owner.get(Owner_.lastName), owner.get(Owner_.firstName));

The results of this query will be ordered alphabetically by the pet owner’s last name, then first name.