//=========================================================== getInt
    // Prompts for an integer in a range.
    // Doesn't handle null (CANCEL) or bad input.
    private static int getInt(String prompt, int min, int max) {
        int result;
        do {
            String strVal = JOptionPane.showInputDialog(null, prompt);
            result = Integer.parseInt(strVal);
            if (result < min || result > max) {
                JOptionPane.showMessageDialog(null,
                 "ERROR: Input must be between " + min + " and " + max);
            }
        } while (result < min || result > max);
        
        return result;
    }