关于判断是否为闰年以及异常处理问题

关于判断闰年问题，我的思路是首先判断输入是否为合法输入，在输入合法的基础上才可以判断是否为闰年，判断输入是否异常代码如下：public static void main(String[] args) {

        String s = " ";
        System.out.println("请输入一个年份：");
        //输入年份
        try {
            BufferedReader in = new BufferedReader(new InputStreamReader(
                    System.in));
            s = in.readLine();
        } catch (IOException e) {
        }
        int year = Integer.parseInt(s);

        Leadyear aaa = new Leadyear();
        boolean leadyear = aaa.judgeyear(year);
        aaa.printLeadyear(year, leadyear);

    }

基于上述已经判断输入合法，进行如下判断输入年份是否为闰年：
    private boolean judgeyear(int year) {
        boolean leadyear;
        if (year % 4 == 0 && year % 100 != 0) {
            leadyear = true;
        } else if (year % 400 == 0) {
            leadyear = true;
        } else
            leadyear = false;
        return leadyear;
    }最后打印结果如下：

  private void printLeadyear(int year, boolean leadyear) {
        if (leadyear)
            System.out.println(year + "是闰年！");
        else
            System.out.println(year + "不是闰年！");
    }
}

测试用例：