private void compute_charges() {
   //
   double total = 0;
   if (tbl_charges_ALM.isEmpty()) {
     total = 0;
   } else {
     List<S2_customers.to_cust_charges> datas = tbl_charges_ALM;
     for (S2_customers.to_cust_charges to : datas) {
       total += to.amount;
     }
   }
   tf_total.setText("" + NumType.with_comma(Double.parseDouble("" + total)));
 }
    @Override
    public Object getValueAt(int row, int col) {
      S2_customers.to_cust_charges tt = (S2_customers.to_cust_charges) getRow(row);

      switch (col) {
        case 0:
          return tt.or;
        case 1:
          return tt.ci_number;
        case 2:
          return NumType.with_comma(tt.amount);

        default:
          return (tt.date_added);
      }
    }