Could not insert into table error in Java Hibernate MySQL Database

Question

In my project I get "could not insert the table error", I'm adding necesarry code parts to here and hope for the best :)

My LogIn Class

package DAO;

import org.hibernate.Hibernate;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.cfg.AnnotationConfiguration;

import tables.Users;


public class LogIn {

    Session session;

    public boolean RegisterUsers(Object user) {

        if (SaveDatabase(user)) {
            return true;
        } else {
            return false;
        }

    }

    public boolean GetUsersWithId(Users user) {

        SessionFactory sessionfactory = new Configuration().configure()
                .buildSessionFactory();
        session = sessionfactory.openSession();

        user = (Users) session.get(Users.class, user.getUserId());
        session.close();
        if (user == null) {
            return false;
        } else {
            return true;
        }

    }

    public boolean SaveDatabase(Object object) {
        try {

            Session session = HibernateUtil.getSessionFactory().openSession();
            Transaction transaction = null;
            Long courseId = null;
            try {
                transaction = session.beginTransaction();
                session.save(object);
                courseId = (Long) session.save(object);
                transaction.commit();
            } catch (Exception e) {
                transaction.rollback();
                System.out.println(e.getMessage());
                return false;
            }
        } finally {
            session.close();
        }
        return true;
    }

}

HibernateUtil

package DAO;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

public class HibernateUtil {
private static final SessionFactory sessionFactory;
static {
    try {
        sessionFactory = new Configuration().configure()
                .buildSessionFactory();
    } catch (Throwable ex) {
        System.err.println("Initial SessionFactory creation failed." + ex);
        throw new ExceptionInInitializerError(ex);
    }
}

public static SessionFactory getSessionFactory() {
    return sessionFactory;
}
}

Test class for these codes

import DAO.LogIn;
import tables.Location;
import tables.Users;

public class Test {
public static void main(String[] args) {
    // Test RegisterUser and GetUsersWithId in here

    LogIn test = new LogIn();
    Users user = new Users();

    user.setUserEmail("email");
    user.setUserAdress("adres here");
    user.setUserFbId(3);
    test.RegisterUsers(user);

}
}

Thanks for help

Edit: Removed config. xml files and auto-created Users class to clean up the mess.

Answer 1

You have a field named session, and a local variable also named session. You open a Hibernate session and assign it to the local variable, but you close the field and not the local variable.

Remove the session field. You shouldn't store a Hibernate Session in a field like that. It doesn't make sense. You'll then get a compilation error that you'll need to fix by declaring the session local variable in a larger scope (outside of the try block).