Correct alternative to SharedSessionContract.createCriteria(Class persistentClass) in Hibernate 5.2

Question

I am upgrading to latest Hibernate 5.2.0 FINAL from Hibernate 3.x. In my old code we were using criteria queries as below.

Session session =getHibernateTemplate().getSessionFactory().getCurrentSession();
Criteria criteria = session.createCriteria(Employee.class);
criteria.add(Restrictions.eq("Department", department));
return criteria.list();

Now from Hibernate 5.2.0 the createCriteria() method has been deprecated. Which can be found from the following documentation.

https://docs.jboss.org/hibernate/orm/5.2/javadocs/deprecated-list.html https://docs.jboss.org/hibernate/orm/5.2/javadocs/org/hibernate/SharedSessionContract.html#createCriteria-java.lang.Class-

The documentation suggests to use JPA Criteria. Below are the few questions I have based on the above background.

1. Since we are not using the EntityManager and heavily dependent on the HibernateDAOSupport and HibernateTemplate , how I can use the JAP Criteria using the session or sessionFactory ?

2. If I use DetachedCriteria as in the below code snippet is it going to be the same as previous implementation or the below code will give us session independent results ?

   DetachedCriteria criteria = DetachedCriteria.forClass(Employee.class);
   criteria.add(Restrictions.eq("Department", department));
   return (List<Employee>) getHibernateTemplate().findByCriteria(criteria);
   

3. Also as an alternative , If I use the DetachedCriteria in below mentioned way is it going to have the same impact as of my old code.

   Session session  =getHibernateTemplate().getSessionFactory().getCurrentSession();
   DetachedCriteria criteria = DetachedCriteria.forClass(Employee.class);
   criteria.add(Restrictions.eq("Department", department));
   return criteria .getExecutableCriteria(session).list();
   

If there is a better way to deal with this please suggest as I don't want to change the use of HibernateDAOSupport and HibernateTemplate.

Answer 1

Use CriteriaBuilder as described below:

//Use below imports:
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Root;

//creating session. This you can create in your own way.
Configuration cfg = new Configuration();
cfg.configure("hibernate.cfg.xml");
cfg.addAnnotatedClass(Employee.class);

SessionFactory factory = cfg.buildSessionFactory();
Session session = factory.openSession();

//**creating CriteriaBuilder**
CriteriaBuilder builder = session.getCriteriaBuilder();
CriteriaQuery<Employee> criteria = builder.createQuery(Employee.class);
Root<Employee> employeeRoot=criteria.from(Employee.class);
criteria.select(employeeRoot);

//**Adding where clause**
criteria.where(builder.equal(employeeRoot.get("employeeId"), "E01"));
List<Employee> employeeList=session.createQuery(criteria).getResultList();