{
facesContext = FacesContext.getCurrentInstance(); // Contexte JSF
// CUIDADO !!!!!!!!! el #{persistenceService} no s'ha de cambiar encara que es canvii de persistence-unit
PersistenceService persistenceService = (PersistenceService) facesContext.getApplication().evaluateExpressionGet(facesContext, "#{persistenceService}", PersistenceService.class);
EntityManager em = persistenceService.getEntityManager();
EntityTransaction transaction = em.getTransaction();
try {