Re: Unable to read after commit () with JPA

Thank you for your reply Robert.

I try to describe the whole picture:

I have 2 JFrame
- one is for CRUD operations on Offer (and for transforming master/
details offer into master/details order), lets call it frmOfferEditor
- one is for searching Order created by frmOfferEditor, lets call it
frmOrderSearch

/* frmOfferEditor */

//transform
The code I posted before it's the code I'm using on frmEditor when I
need transforming master/details offer into master/details order.

//CRUD
The code I use for CRUD operations uses an EM called entityManager.
Here is the code:

//CRUD - Create
try {
    entityManager.getTransaction().rollback();
    entityManager.getTransaction().begin();
    offerta = new offerta.Offerte();
    numOfferta = 0;
    Object res = entityManager.createQuery("SELECT MAX(o.numOfferta) FROM
Offerte o WHERE o.anno = :anno").setParameter("anno",
anno).getSingleResult();
    if (res != null) {
        numOfferta = (Integer) res;
    }
    numOfferta++;
    offerta.setNumOfferta(numOfferta);
    entityManager.persist(offerta);
} catch (Exception ex) {
    ex.printStackTrace();
}

// CRUD - Save
try {
    entityManager.getTransaction().commit();
    entityManager.getTransaction().begin();
} catch (RollbackException rex) {
     rex.printStackTrace();
     entityManager.getTransaction().begin();
     List<offerta.Offerte> merged = new
ArrayList<offerta.Offerte>(list.size());
     for (offerta.Offerte o : list) {
         merged.add(entityManager.merge(o));
     }
     list.clear();
     list.addAll(merged);
 }

/* frmOrderSearch */
try {
    entityManager.getTransaction().rollback();
    entityManager.getTransaction().begin();
    String query = ....
    Query q = entityManager.createQuery(query).setParameter(.....)
    java.util.Collection data = q.getResultList();
    list.clear();
        list.addAll(data);
} catch (Exception ex) {
    ex.printStackTrace();
}

I hope that now it's clear