}
if ((idArt % 2) == 0) { //pair
a = new ServicePersistantImpl(idArt);
a.setNom("article_service_" + idArt);
} else { //impair
a = new MaterielPersistantImpl(idArt);
a.setNom("article_materiel_" + idArt);
}
pm.makePersistent(a);
a.setCatalogue(cat);
mar.getArticles().add(a);