// Add course method
  public void addCourse() {
    try {
      Database db = new Database();

      String coursename = (String) coursecombobox.getSelectedItem();
      if (coursecombobox.getSelectedIndex() == 0) {
        throw new Exception("No course selected");
      }

      float fees = db.getCoursefees(coursename);
      float totalfees = fees + (ims.main.Settings.getInstallment() * (int) spinner.getValue());

      long id = (long) table.getValueAt((int) table.getSelectionModel().getMinSelectionIndex(), 0);

      db.addCourseToCurrentStudent(id, totalfees, (int) spinner.getValue(), coursename);

      updateFeesData(id);
      courseReset();
    } catch (Exception e) {
      JOptionPane.showMessageDialog(this, e.getMessage(), null, JOptionPane.ERROR_MESSAGE);
    }
  }
 // Reset combobox and spinner
 private void courseReset() {
   coursecombobox.setSelectedIndex(0);
   spinner.setValue(0);
 }