UnknownServiceException: ConnectionProvider in Hibernate 4

Question 1

We've got the tests passing now. It was actually a problem with our transaction handling leaking into non-transactional tests. Our transaction support extended Spring's TransactionAspectSupport, and with Hibernate 3 this used to work in non-transactional tests by doing nothing. In Hibernate 4 it now fails in a roundabout way, when it tries to create a transaction with a shut-down session factory.

We modified the way tests were set up so that it wouldn't try doing any transactional stuff at all unless we were in a transactional test, and they now pass happily.

Moral: One of the perils of using a singleton is that it can easily leak stuff across tests.

Question 2

You should create Session Factory object only once in application and you should not destroy in your whole application. If you are trying to the close the once created session factory object and want to use same object so you will get this above exception ie. Error creating Session: org.hibernate.service.UnknownServiceException: Unknown service requested [org.hibernate.engine.jdbc.connections.spi.ConnectionProvider] So in above scenario you should create the hibernate util and define fields as below:

import org.hibernate.HibernateException;
import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistry;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
public class HibernateUtil {

private static Configuration configuration;
private static StandardServiceRegistry builder;
private static SessionFactory factory;

static {
try {
configuration = new Configuration().configure("/com/hibernate/hibernate.cfg.xml");
builder = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();
factory = configuration.buildSessionFactory(builder);
} catch (HibernateException he) {
System.err.println("Error creating Session: " + he);
throw new ExceptionInInitializerError(he);
}
}

public static SessionFactory getSessionFactory() {
return factory;
}

public static void closeSessionFactory() {
if (factory != null) {
try {
StandardServiceRegistryBuilder.destroy(builder);
} catch (Exception e) {
e.printStackTrace();
}
}
}
}

Question 3

Something like this happened to me before. It was solved when I changed the IP of the database from 127.0.0.1 to 192.168.1.27 (the IP of my computer in my network, it can be found doing ip config in windows or ifconfig in linux). It might not be a permanent solution, but it dodges a bullet.

Question 4

Session object in Hibernate is not thread safe, you should not use the same session in different threads, unless you synchronize access to Session object.

And if you really want to use that trick then I like to say you that every time clear and close session after transaction is complete. Or just use openSession() so that way your program will work and will execute.