输入年份和月份，输出这个月的天数

public class ShowCalendar {

    public static void main(String[] args) {
        List<String> date = getDate(2022, 0);
    }

    public static List<String> getDate(Integer year, Integer month) {
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.YEAR, year);
        calendar.set(Calendar.MONTH, month);
        calendar.set(Calendar.DATE, 1);
        int days = calendar.getActualMaximum(Calendar.DATE);
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
        ArrayList<String> list = new ArrayList<>();
        for (int i = 1; i <= days; i++) {
            String stdate = sdf.format(calendar.getTime());
            System.out.println(stdate);//输出日期
            calendar.set(Calendar.DATE, calendar.get(Calendar.DATE) + 1);
            list.add(stdate);
        }
        return list;

    }
}