Java DayOfWeek minus()方法及示例

java.time.DayOfWeek 的 minus() 方法是Java中的一个内置函数，它接收一个长整数作为参数，并按照所传递的参数指定的时间向后或向前推进一些日子后，返回DayOfWeek的实例。该计算围绕一周的末尾从周一滚动到周日。指定的周期可以是正数或负数。

方法声明 。

public DayOfWeek minus(long days)

语法

DayOfWeek dayOfWeekObject = dayOfWeekObject.minus(long days)

参数： 该方法将天数作为参数，其中。

• days – 是要向前或向后推进的天数。
• dayOfWeekObject – 是DayOfWeek对象的一个实例。

返回值： 该函数在向后或向前推进一些天数后返回DayOfWeek的一个实例。

以下程序说明了上述方法：

程序 1 :

// Java Program Demonstrate minus()
// method of DayOfWeek
import java.time.DayOfWeek;
  
class DayOfWeekExample {
    public static void main(String[] args)
    {
        // Getting an instance of DayOfWeek from int value
        DayOfWeek dayOfWeek = DayOfWeek.of(2);
  
        // Printing the day of the week and its Int value
        System.out.println("Day of the Week : "
                           + dayOfWeek.name() + " - "
                           + dayOfWeek.getValue());
  
        // Number of days to advance
        long adv = 10;
  
        // Advancing the day
        dayOfWeek = dayOfWeek.minus(adv);
  
        // Printing the day of the week and its
        // Int value before adv days
        System.out.println("Day of the Week before "
                           + adv + " days: "
                           + dayOfWeek.name() + " - "
                           + dayOfWeek.getValue());
    }
}

输出:

Day of the Week : TUESDAY - 2
Day of the Week before 10 days: SATURDAY - 6

程序2

// Java Program Demonstrate minus()
// method of DayOfWeek
import java.time.DayOfWeek;
  
class DayOfWeekExample {
    public static void main(String[] args)
    {
        // Getting an instance of DayOfWeek
        // from int value
        DayOfWeek dayOfWeek = DayOfWeek.of(7);
  
        // Printing the day of the week
        // and its Int value
        System.out.println("Day of the Week : "
                           + dayOfWeek.name()
                           + " - "
                           + dayOfWeek.getValue());
  
        // Number of days to advance
        long adv = -3;
  
        // Advancing the day
        dayOfWeek = dayOfWeek.minus(adv);
  
        // Printing the day of the week and its
        // Int value before adv days
        System.out.println("Day of the Week before "
                           + adv + " days: "
                           + dayOfWeek.name()
                           + " - "
                           + dayOfWeek.getValue());
    }
}

输出:

Day of the Week : SUNDAY - 7
Day of the Week before -3 days: WEDNESDAY - 3

参考资料: https://docs.oracle.com/javase/8/docs/api/java/time/DayOfWeek.html#minus-long-