public class HibernateUtilMongo {

    private static final Logger log = Logger.getLogger(HibernateUtilMongo.class.getName());
    private static final SessionFactory sessionFactory;
    private static final ServiceRegistry serviceRegistry;

    static {
        try {
            // create a new instance of OmgConfiguration
            OgmConfiguration cfgogm = new OgmConfiguration();

            // enable JTA strategy
            cfgogm.setProperty(Environment.TRANSACTION_STRATEGY, "org.hibernate.transaction.JTATransactionFactory");
            cfgogm.setProperty(Environment.CURRENT_SESSION_CONTEXT_CLASS, "jta");

            // specify JTA platform
            cfgogm.setProperty(Environment.JTA_PLATFORM, "org.hibernate.service.jta.platform.internal.JBossStandAloneJtaPlatform");

            // in order to select the local JBossJTA implementation it is necessary to specify these properties
            cfgogm.setProperty("com.arjuna.ats.jta.jtaTMImplementation", "com.arjuna.ats.internal.jta.transaction.arjunacore.TransactionManagerImple");
            cfgogm.setProperty("com.arjuna.ats.jta.jtaUTImplementation", "com.arjuna.ats.internal.jta.transaction.arjunacore.UserTransactionImple");

            //configure MongoDB connection
            cfgogm.setProperty("hibernate.ogm.datastore.provider", "mongodb");
            cfgogm.setProperty("hibernate.ogm.datastore.grid_dialect", "org.hibernate.ogm.dialect.mongodb.MongoDBDialect"); //you can ignore this setting
            cfgogm.setProperty("hibernate.ogm.mongodb.database", "Messenger");
            cfgogm.setProperty("hibernate.ogm.mongodb.host", "127.0.0.1");
            cfgogm.setProperty("hibernate.ogm.mongodb.port", "27017");

            //add our annotated class
            cfgogm.addAnnotatedClass(Message.class)
                    .addAnnotatedClass(History.class);

            // create the SessionFactory
            serviceRegistry = new ServiceRegistryBuilder().applySettings(cfgogm.getProperties()).buildServiceRegistry();
            sessionFactory = cfgogm.buildSessionFactory(serviceRegistry);
        } catch (Throwable ex) {
            log.log(Level.SEVERE, "Initial SessionFactory creation failed !", ex);
            throw new ExceptionInInitializerError(ex);
        }
    }

    /**
     * Get the SessionFactory
     *
     * @return SessionFactory
     */
    public static SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}