@Entity
public class userDetails {
@Id
private int userId;
private String userName;
  //setters and getters
}

package firstHibernateproj;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

public class hibernateclass {
public static void main(String[] args) {
    userDetails user=new userDetails();
    user.setUserId(1);
    user.setUserName("madhu");
    SessionFactory sessionfactory=new Configuration().configure().buildSessionFactory();
    Session session=sessionfactory.openSession();
    session.beginTransaction();
    session.save(user);
    session.getTransaction().commit();
}

}

Exception in thread "main" org.hibernate.QueryTimeoutException: Cannot open connection