My understanding is that the Hibernate Criteria API is deprecated:
As of Hibernate 5.2, the JPA Criteria API should be used instead
But in Hibernate Criteria API, building complex queries with JOINs was easy. I could do it as follows:
Criteria criteriaQuery = session.createCriteria(Request.class);
// 1. Prepare aliases (JOINs) from main table
if (!StringUtils.isBlank(searchCriteria.getRequestorName())) {
criteriaQuery.createAlias("requestor", "npRequestor", JoinType.INNER_JOIN);
}
if (!StringUtils.isBlank(searchCriteria.getApproverName())) {
criteriaQuery.createAlias("workflows", "wf", JoinType.INNER_JOIN);
criteriaQuery.createAlias("wf.approver", "npApprover", JoinType.INNER_JOIN);
}
// Prepare criteria
// ...
criteriaQuery.add(Restrictions.eq("wf.someAttribute", someAttr));
}
But doing JOINs and complex queries in JPA Criteria API is extremely difficult. As one user noted in this thread, "I'm having a hard time creating complex joins using Criteria API and not finding extensive documentation and examples."
A simple Join requires the creation of a Metamodel (a separate process), then an EntityType, and the syntax is hard to construct. The below is just the simplest example possible, but I have multiple If/Else conditions and multi-way Joins.
CriteriaQuery<Pet> cq = cb.createQuery(Pet.class);
Metamodel m = em.getMetamodel();
EntityType<Pet> Pet_ = m.entity(Pet.class);
EntityType<Owner> Owner_ = m.entity(Owner.class);
Root<Pet> pet = cq.from(Pet.class);
Join<Owner, Address> address = cq.join(Pet_.owners).join(Owner_.addresses);
Why are people shooting themselves in the foot? Why deprecate something perfectly usable in favor of an unwieldy and hard-to-use alternative?
