below is my hibernate code:

```
SessionFactory sessionFactory;
        Session session = null;
        LoginEntity user = null;

        try {

            sessionFactory = HibernateUtility.getSessionFactory();
            session = sessionFactory.openSession();
            session.beginTransaction();

            user = session.get(LoginEntity.class, user_id);

            System.out.println(user.getUserCountryMapping()); // if I remove this line I get error..

            session.getTransaction().commit();
            return user;

        } catch (Exception e) {
            Logger.getLogger(BulkActionMethods.class.getName()).log(Level.SEVERE, null, e);
        } finally {
            if (session != null) {
                session.close();
            }
        }

```

I am facing a weird issue with my code, When I remove the `System.out.println(user.getUserCountryMapping());` line I am getting `HTTP Status 500 - Internal Server Error` error on browser but when I write this line I am getting expacted `JSON` response on browser..
Please someone help me to understand this issue.