Hibernate is not releasing mysql connection..

monaj.at.tcs · **Joined:** Sat Jan 18, 2014 5:55 am **Posts:** 1

Hello all,

I am new to hibernate. I am creating some basic hibernate program to doing some insert into MySql database. The below is the main code I have written. Although I am closing the session after transaction and seeing that " Released JDBC connection" on console, I can see an inactive connection in the database after running the program.Everytime I am runnning the programm a new inactive connection is getting created in the database. I have to click "terminate" button in eclips console to stop that inactive session everytime.

Code:

[color=#404080]
Student s1=new Student();
   s1.setName("Monaj");
   s1.setRoll(1);
   s1.setDate(new Date());

Configuration configuration=new Configuration().configure();
serviceRegistry = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();
sessionFactory = configuration.configure().buildSessionFactory(serviceRegistry);
    
Session session=sessionFactory.openSession();
Transaction t1=session.beginTransaction();
session.save(s1);
t1.commit();
session.close();[/color]

Console output:-
15:29:08.476 [main] DEBUG o.h.e.j.i.LogicalConnectionImpl - Aggressively releasing JDBC connection
15:29:08.476 [main] DEBUG o.h.e.j.i.LogicalConnectionImpl - Releasing JDBC connection
15:29:08.476 [main] DEBUG o.h.e.j.i.LogicalConnectionImpl - Released JDBC connection
15:29:08.477 [main] DEBUG o.h.e.j.internal.JdbcCoordinatorImpl - HHH000420: Closing un-released batch
15:29:37.323 [pool-1-thread-1] DEBUG o.h.e.j.c.i.DriverManagerConnectionProviderImpl - Connection pool now considered primed; min-size will be maintained

Hibernate Configuration:-

<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost/test</property>
<property name="connection.password">password</property>
<property name="connection.username">admin</property>
<property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
<property name="show_sql">true</property>
<property name="hbm2ddl.auto">create</property>
<property name="connection.release_mode">AFTER_TRANSACTION</property>
<property name="connection.autocommit">true</property>

Could anyone please help me on this.

molavec · **Joined:** Sun Jul 13, 2014 11:36 pm **Posts:** 3

Is there a solution for these issue?

sanne.grinovero · **Posted:** Mon Jul 14, 2014 9:53 am

To terminate Hibernate you have to close the SessionFactory.

Otherwise managed connection pools will do their job by design: try and keep a pool of connections open to reuse. This is essential to achieve good performance.

molavec · **Joined:** Sun Jul 13, 2014 11:36 pm **Posts:** 3

Thanks Sanne,

I was checking out documentation to try understand how hibernate works. In my situation, I use hibernate in a JPA example. The next example code is working with Eclipselink and Datanucleus.

Code:

package cl.molavec.jpa.tests;

import java.util.List;
import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.Query;
import org.hibernate.SessionFactory;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import cl.molavec.jpa.entities.QUser;

public class Example01 {
   
     private static final String PERSISTENCE_UNIT_NAME = "jpa_test01";
     private static EntityManagerFactory factory;     
     private static Logger logger = LoggerFactory.getLogger(Example01.class);

     public static void main(String[] args) {
      
       factory = Persistence.createEntityManagerFactory(PERSISTENCE_UNIT_NAME);
       EntityManager em = factory.createEntityManager();
       // read the existing entries and write to console
       
       
       
       // create new todo
       em.getTransaction().begin();
       QUser user = new QUser();
       user.setUsername("User13");
       em.persist(user);
       em.getTransaction().commit();

       Query q = em.createQuery("select t from QUser t");
       List<QUser> userList = q.getResultList();
       
       for (QUser usern : userList) {
         System.out.println(usern);
       }
       
       System.out.println("Size: " + userList.size());
       
       em.close();
     
       logger.info("------------> End Program");
     }
}

With Hibernate I has the problem showed above. My problem is how to get Session object (I think this should be the object to close).

I other way, I tried to add the next property in persistence.xml, but it doesn't make any difference:

Code:

Is possible to include those properties in this file or it should be in hibernate.cfg.xml.

Thanks in advance.

sanne.grinovero · **Posted:** Mon Jul 14, 2014 6:54 pm

you don't need to set such properties, as for example "connection.release_mode" applies to the end of the specific Session or the specific EntityManager instance.

What you need to do is - when your program is done - to close the SessionFactory or the EntityManagerFactory (depending if you're using the Hibernate classical interface or the JPA interface)

So in your case:

Code:

factory.close();

molavec · **Joined:** Sun Jul 13, 2014 11:36 pm **Posts:** 3

Sanne,

That was fast! Thank you very much this works!