I have a parent entity and a child entity. It uses a join table to hold the
relationship. When I do a get on the parent it retrieves the children
correctly but when I call merge on the parent after adding some children, it
tries to persist the children in the child table not into the join table. A
is a basic outline of my code is below. I don't understand why the get is
working but the mere is working this way. Am I missing something obvious?
Parent:
@Entity
public class Role extends CoreObject{
@OneToMany(cascade={CascadeType.ALL})
private List <Permission> permissions;
/**
* @param permissions the permissions to set
*/
public void setPermissions(List <Permission> permissions) {
this.permissions = permissions;
}
/**
* @return the permissions
*/
public List <Permission> getPermissions() {
return permissions;
}
}
Child:
@Entity
public class Permission extends CoreObject{
}
I call merge like so :
public void merge(CoreObject co){
EntityManagerFactory emf =
Persistence.createEntityManagerFactory(ConfigUtils.getParameter(Constants.Pa
ram_PersistenceUnit));
threadLocal = new ThreadLocal<EntityManager>();
em = threadLocal.get();
em = emf.createEntityManager();
threadLocal.set(em);
em.getTransaction().begin();
em.merge(co);
em.getTransaction().commit();
em.close();
}
