java 根据时间 获取时间的天数、包含闰年和不闰年

1:————————————————————————————————————————————————————————————————————————————————————

int days =31; // 根据年月算当月的天数
//			String month = timeInfo;
switch (mReq) {
case "01":
case "03":
case "05":
case "07":
case "08":
case "10":
case "12":
System.out.println(mReq + "月份有：31天");
days=31;
break;
//对于2月份需要判断是否为闰年
case "02":
if ((yearReq % 4 == 0 && yearReq % 100 != 0) || (yearReq % 400 == 0)) {
days=29;
System.out.println(mReq + "月份有：29天");
break;
} else {
System.out.println(mReq + "月份有：28天");
days=28;
break;
}
case "04":
case "06":
case "09":
case "11":
System.out.println(mReq + "月份有：30天");
days=30;
break;
default:
System.out.println("请输入正确的年份和月份");
break;
}

2：————————————————————————————————————————————————————————————————————————————————————————————
public static void main(String[] args) throws ParseException {
//方法1
String strDate = "2013-02-02";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM");
Calendar calendar = new GregorianCalendar();
Date date1 = sdf.parse(strDate);
calendar.setTime(date1); //放入你的日期
System.out.println("天数为=" + calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
//		//方法2
//		System.out.println("天数为=" + new Date(2007,02,0).getDate());

}