Java 计算今天是这周的第几天 这月 这年

Calendar calendar = Calendar.getInstance();
//时间，可以为具体的某一时间
Date today = new Date();
calendar.setTime(today);
int weekDay = calendar.get(Calendar.DAY_OF_WEEK);
int monthDay = calendar.get(Calendar.DAY_OF_MONTH);
int yearDay = calendar.get(Calendar.DAY_OF_YEAR);
if (weekDay == 1) {
    weekDay = 7;
} else {
    weekDay = weekDay - 1;
}
System.out.println("当前时间是，本周的第" + weekDay  + "天");
System.out.println("当前时间是，本月的第" + monthDay + "天");
System.out.println("当前时间是，本年的第" + yearDay  + "天");