public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
        if (qName.equals("annonce")) {

            if (currentFacture != null) {
                throw new IllegalStateException("already processing a voys");
            }
            currentFacture = new Facture();
        } else if (qName.equals("id_facture")) {
            id_factureT = "open";
        } else if (qName.equals("n_serie")) {
            n_serieT = "open";
        } else if (qName.equals("somme_facture")) {
            somme_factureT = "open";
        } else if (qName.equals("date_payement_facture")) {
            date_payement_factureT = "open";
        } 
    }