用 Java 获取每月的最后一个星期五

2022-01-11 00:00:00 date calendar java

我正在开展一个项目,要求将日期计算为给定月份的最后一个星期五.我想我有一个只使用标准 Java 的解决方案,但我想知道是否有人知道更简洁或更高效的方法.以下是我今年测试的内容:

I am working on a project where the requirement is to have a date calculated as being the last Friday of a given month. I think I have a solution that only uses standard Java, but I was wondering if anyone knew of anything more concise or efficient. Below is what I tested with for this year:

    for (int month = 0; month < 13; month++) {
        GregorianCalendar d = new GregorianCalendar();
        d.set(d.MONTH, month);
        System.out.println("Last Week of Month in " + d.getDisplayName(d.MONTH, Calendar.LONG, Locale.ENGLISH) + ": " + d.getLeastMaximum(d.WEEK_OF_MONTH));
        d.set(d.DAY_OF_WEEK, d.FRIDAY);
        d.set(d.WEEK_OF_MONTH, d.getActualMaximum(d.WEEK_OF_MONTH));
        while (d.get(d.MONTH) > month || d.get(d.MONTH) < month) {
            d.add(d.WEEK_OF_MONTH, -1);
        }
        Date dt = d.getTime();
        System.out.println("Last Friday of Last Week in  " + d.getDisplayName(d.MONTH, Calendar.LONG, Locale.ENGLISH) + ": " + dt.toString());
    }

推荐答案

基于 marked23 的建议:

public Date getLastFriday( int month, int year ) {
   Calendar cal = Calendar.getInstance();
   cal.set( year, month + 1, 1 );
   cal.add( Calendar.DAY_OF_MONTH, -( cal.get( Calendar.DAY_OF_WEEK ) % 7 + 1 ) );
   return cal.getTime();
}

相关文章