Question

Is it possible with JPA to retrieve a instances of a non-entity classes with native queries?
I have a non-entity class that wraps two entities:

class Wrap{
  Entity1 ent1;
  Entity2 ent2
}
@Entity
class Entity1{
  ...
}
@Entity
class Entity2{
  ...
}

How can I do something like that?

Query q = entityManager.createNativeQuery("native select here");
List<Wrap> list = q.getResultList();

Answer 1

Is it possible with JPA to retrieve a instances of a non-entity classes with native queries?

No. Native queries can return entities only (if you tell them to do so by passing the resultClass or a resultSetMapping to the createNativeQuery method; if you don’t, you will get collections of raw data).

In JPQL, you can use constructor expressions (SELECT NEW…) whith a non-entity constructor. But this is not supported for native queries, you’ll have to do it manually.