private void jButton27ActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_jButton27ActionPerformed
        // TODO add your handling code here:
        List<Kelas> lk = new ArrayList<>();
        List<String> ls = new ArrayList<>();
        KelasController kk = new KelasController();
        int i = 0;
        try {
            lk = kk.getAll();


        } catch (SQLException ex) {
            Logger.getLogger(FormInduk.class
                    .getName()).log(Level.SEVERE, null, ex);
        }
        jComboBox2.removeAllItems();
        for (Kelas k : lk) {
            ls.add((k.getKelas()));
        }
        for (String s : ls) {
            jComboBox2.addItem(s);
            System.out.println("" + s);
        }
        CardLayout cad = (CardLayout) kontenAd.getLayout();
        cad.show(kontenAd, "daftarAd");

    }