/* - */
  void jButton4_actionPerformed(ActionEvent e) {
    int rowSelected = jTable1.getSelectedRow();

    if (rowSelected != -1) {
      MyTableModel tm = (MyTableModel) jTable1.getModel();
      data = tm.removeRow(rowSelected);
    }
  }
 /* + */
 void jButton3_actionPerformed(ActionEvent e) {
   // Add a row to the table
   MyTableModel tm = (MyTableModel) jTable1.getModel();
   data = tm.insertRow();
 }