Java中的 DayOfWeek plus() 方法及示例

Java .time.DayOfWeek的plus()方法是Java中的一个内置函数，它以一个长整数作为参数，并根据传递的参数指定的向前或向后推进几天后返回 DayOfWeek 的实例。计算从周日到周一在一周结束时滚动。指定的时间段可以是正数或负数。

方法声明：

public DayOfWeek plus(long days)

句法：

DayOfWeek dayOfWeekObject = dayOfWeekObject.plus(long days)

参数：此方法以天为参数，其中：

天- 是前进或后退的天数。

dayOfWeekObject – 是 DayOfWeek 对象的一个实例。

返回值：该函数在向前或向后推进几天后返回一个 DayOfWeek 的实例。

下面的程序说明了上述方法：
方案一：

// Java Program Demonstrate plus()
// 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.plus(adv);
  
        // Printing the day of the week and its
        // Int value after adv days
        System.out.println("Day of the Week after "
                           + adv + " days: "
                           + dayOfWeek.name() + " - "
                           + dayOfWeek.getValue());
    }
}

输出：

Day of the Week : TUESDAY - 2
Day of the Week after 10 days: FRIDAY - 5

方案二：

// Java Program Demonstrate plus()
// 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.plus(adv);
  
        // Printing the day of the week and its
        // Int value after adv days
        System.out.println("Day of the Week after "
                           + adv + " days: "
                           + dayOfWeek.name()
                           + " - "
                           + dayOfWeek.getValue());
    }
}

输出：

Day of the Week : SUNDAY - 7
Day of the Week after -3 days: THURSDAY - 4

参考： https: Java/time/DayOfWeek.html#plus-long-