有什么好方法可以得到即将到来的星期三的日期

问题描述

有没有什么好的方法可以获取下周三的日期?即如果今天是星期二，我想得到这周星期三的日期；如果今天是星期三，我想得到下星期三的日期；如果今天是星期四，我想得到下周星期三的日期.

Is there a good way to get the date of the coming Wednesday? That is, if today is Tuesday, I want to get the date of Wednesday in this week; if today is Wednesday, I want to get the date of next Wednesday; if today is Thursday, I want to get the date of Wednesday in the following week.

谢谢.

推荐答案

基本算法如下:

• 获取当前日期
• 获取星期几
• 找出与星期三的不同之处
• 如果差值不是正数，则加 7(即坚持下一个/未来日期)
• 添加差异

这里有一个片段展示如何使用 java.util.Calendar 来做到这一点:

Here's a snippet to show how to do this with java.util.Calendar:

import java.util.Calendar;

public class NextWednesday {
    public static Calendar nextDayOfWeek(int dow) {
        Calendar date = Calendar.getInstance();
        int diff = dow - date.get(Calendar.DAY_OF_WEEK);
        if (diff <= 0) {
            diff += 7;
        }
        date.add(Calendar.DAY_OF_MONTH, diff);
        return date;
    }
    public static void main(String[] args) {
        System.out.printf(
            "%ta, %<tb %<te, %<tY",
            nextDayOfWeek(Calendar.WEDNESDAY)
        );
    }
}

相对于我的此时此地，上述代码段的输出是 "Wed, Aug 18, 2010".

Relative to my here and now, the output of the above snippet is "Wed, Aug 18, 2010".

• java.util.Calendar
• java.util.Formatter - 用于格式化字符串语法