Can not refresh not managed object

Question

I've to refresh a list of `Eleve` from the database to a Jtable. The `Jtable` it's self is bound to an observable `list< Eleve >`, so any add/delete to the list is automatically updated in the `Jtable`. My code explain it's self: ``` EleveJpaController ejc = new EleveJpaController(emf); java.util.Collection data = ejc.findEleveByNiveauClasseNomPrenom(niv, classe, nom, prenom); for (Eleve entity : data) { entityManager.refresh(entity); } list.clear(); list.addAll(data); ``` List< Eleve > findEleveByNiveauClasseNomPrenom(a,v,x,n): ``` public List findEleveByNiveauClasseNomPrenom(String niv,String classe,String nom, String prenom) { EntityManager em = getEntityManager(); Query qr= em.createQuery("SELECT e FROM Eleve e WHERE e.niv.niv like '%"+niv+"%' and e.class1.libelle like '%"+classe+"%' and e.nom like '%"+nom+"%' and e.prenom like '%"+prenom+"%'"); return qr.getResultList(); } ``` As you can see, It's well manged list of `Eleve` objects.. So why this exception is thrown…

Accepted Answer

You're probably using a different EntityManager to refresh your entities than the one which loads the entities from the database. The entities are not managed in the new EntityManager. According to the javadoc, the exception is the normal behaviour for not managed entities. Either use the same EntityManager, or use merge() to make your objects managed

Can not refresh not managed object

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