In Spring Boot application with HikariCP dataSource I've execute HQL queries with helper class:
public class QueryExecutor {
private Session session;
@Autowired
private SessionFactory sessionFactory;
public QueryExecutor getConnection() {
session = sessionFactory.openSession();
session.beginTransaction();
return this;
}
public void closeConnection() {
session.getTransaction().commit();
session.close();
}
public List execute(String hql, Long limit, Long offset) {
getConnection();
Query query = session.createQuery(hql);
List list = query.list();
closeConnection();
return list;
}
It works ok, but when I start using class widely, application starts freezes because Hibernate Session is closed randomly and transaction wait 30 seconds (default timeout value for HikariCP transactions) before get Session is closed error (or currentPersistenceContext is null if I used getCurrentSession() instead openSesssion()).
First of all, I changed open session to getCurrentSession function. But I also need to specify context with @PersistenceContext or hibernate.current_session_context_class=thread in hibernate.cfg.xml. I read that this property better to use with default value. Also I specify hibernate.connection.release_mode=AFTER_TRANSACTION. But that isn't solve a problem.
After all, I changed class like that:
@PersistenceContext
private EntityManager entityManager;
@Transactional
public List execute(String hql, Long limit, Long offset) {
Query query = entityManager.createQuery(hql);
return query.getResultList();
}
and use javax.persistence.Query instead Hibernate queries. Now it works ok. But is that a correct modifications? All functions worked with execute method of QueryExecutor annotated with @Transactional. As I uderstood, in that case no beginTransaction() needed. But need I close entityManager after execute() ?
SessionFactory used with Hibernate without JPA and EntityManager used with Hibernate JPA technologies?
How can I solve problem without using EntityManager?
