persist method giving PersistentObjectException on trying to persist a new Object

Question

In my below code i am trying to persist a newly created instance of Employee, it is throwing persistantobject exception :

public class abc
{
   public static void main(String as[])
   {
       Configuration cfg= new Configuration();System.out.println("--------------got cfg object-----------");
       cfg = cfg.configure("hibernate.cfg.xml");System.out.println("--------------hbm loaded into cfg-----------");
       SessionFactory sf= cfg.buildSessionFactory();
       Employee item3 = new Employee();
       item3.setEid(420);
       Session session = sf.openSession(); 
       Employee item = (Employee) session.get(Employee.class, new Integer(12));
      // item.setFname("myaim1"); 
      // session.save(item);

     // Integer a= (Integer)session.save(item3);
       //session.persist(item3);
       Transaction tx = session.beginTransaction();
       session.persist(item3);
        tx.commit(); 
       session.close(); // end of first session, item is detached  

   }}

And exception is :

-------------hbm loaded into cfg-----------
Hibernate: select employee0_.eid as eid0_0_, employee0_.first_name as first2_0_0_, employee0_.last_name as last3_0_0_, employee0_.email as email0_0_ from EMPLOYEE3 employee0_ where employee0_.eid=?
Exception in thread "main" org.hibernate.PersistentObjectException: detached entity passed to persist: Employee
    at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:79)
    at org.hibernate.event.def.DefaultPersistEventListener.onPersist(DefaultPersistEventListener.java:38)
    at org.hibernate.impl.SessionImpl.firePersist(SessionImpl.java:618)
    at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:592)
    at org.hibernate.impl.SessionImpl.persist(SessionImpl.java:596)
    at abc.main(abc.java:23)

i am using hibernate core ver 4.3. Whats gone wrong ?

Answer 1

Is there any particular reason for using persist() here ? Why are you not using save() ?

Something like this :

Session session = HibernateUtil.getSessionFactory().openSession();

session.beginTransaction();
session.save(item3);
session.getTransaction().commit();

Answer 2

Most probably the error is at the line item3.setEid(420); . I guess you must be using @Id with @GeneratedValue with one of `SEQUENCE/IDENTITY/TABLE/AUTO'. If so, you can comment out this line as try.

If you continue to face the same issue, posting the Employee class would help further debug it.