public void actionPerformed(ActionEvent event)
    {
    if (comboBox.isEditable())
      {
      String newEntry = entryToUpperCase();

      if (!newEntry.equals(Files.REVERT))
        {
        FileParser.writeFile(newEntry+Files.PRESET_EXTENSION);

        if (!exists(newEntry))
          comboBox.addItem(newEntry);
        }

      comboBox.setEditable(false);
      }
    }