How to do it with JPA Criteria API?

Question

How can I do Criteria Query in JPA2, which is equivalent to this JPQL with and without using metamodel?

SELECT p FROM Employee e JOIN e.phones p WHERE e=:empl

score 1 · Accepted Answer · answered Jul 14 '13 at 14:24

CriteriaBuilder cb = em.getCriteriaBuilder();
CriteriaQuery<Phone> criteriaQuery = cb.createQuery(Phone.class);
Root<Employee> employee = criteriaQuery.from(Employee.class);
CollectionJoin<Employee, Phone> phone = employee.join(Employee_.phones);
criteriaQuery.where(cb.equal(employee, empl);
criteriaQuery.select(phone);
TypedQuery<Phone> query = em.createQuery(criteriaQuery);
List<Phone> phones = query.getResultList();

That said, I see no point in replacing a simple, obvious JPQL query with the horrendous, unreadable lines of code above. Criteria queries are useful to dynamically construct queries, but JPQL shines for static queries like the one you have.

Thanks for your answer. It works. I agree, that it is no point replacing that simple JPQL. I have dynamical query, but just this part I didn't know how to do. — srnjak, Jul 14 '13 at 14:58

How to do it with JPA Criteria API?

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