年月日计算

最近在做一个类似ios的日期 pickerView
看到一个别人的demo其实, 计算对应的年月日很简单

 /** * @param year * @param month * @return */
        private int getDay(int year, int month) {
            int day = 30;
            boolean flag = false;
            switch (year % 4) {
                case 0:
                    flag = true;
                    break;
                default:
                    flag = false;
                    break;
            }
            switch (month) {
                case 1:
                case 3:
                case 5:
                case 7:
                case 8:
                case 10:
                case 12:
                    day = 31;
                    break;
                case 2:
                    day = flag ? 29 : 28;
                    break;
                default:
                    day = 30;
                    break;
            }
            return day;
        }