Question

我想要一些Java代码，它会根据当前时间告诉我学校何时开放。

当我在上午9点到下午6点之间调用此方法时，应该返回“学校开放”，否则应在下午6点之后和上午9点之前返回“学校关闭”。

public Calendar shopStartTime(String msg)
{
    Calendar currentTime = Calendar.getInstance();
    Calendar schoolTime = Calendar.getInstance();
    Calendar schoolClosedTime = Calendar.getInstance();
    schoolTime.set(Calendar.HOUR_OF_DAY, 9);
    schoolTime.set(Calendar.MINUTE, 0);
    schoolTime.set(Calendar.SECOND, 0);
    schoolTime.set(Calendar.MILLISECOND, 0);
    schoolClosedTime.set(Calendar.HOUR_OF_DAY, 18);
    schoolClosedTime.set(Calendar.MINUTE, 0);
    schoolClosedTime.set(Calendar.SECOND, 0);
    schoolClosedTime.set(Calendar.MILLISECOND, 0);
    if (schoolTime.compareTo(currentTime) <= 0 && 
       (currentTime.compareTo(schoolClosedTime)>=0))
    {
        // check for time
        Toast.makeText(getSherlockActivity(), "school is closed ", 
            Toast.LENGTH_SHORT).show();
    }
    else 
    {
        Toast.makeText(getSherlockActivity(), " school is open", 
            Toast.LENGTH_SHORT).show();
    }
    return currentTime;
}

但代码无效，因为它总是返回相同的结果。如何测试一次是否在两个其他时间之间？

Answer 1

阅读javadocs！

if (currentTime.after(schoolTime) && currentTime.before(schoolClosedTime)) {
    // school is open
} else {
    // school is closed
}

Answer 2

检查小时是否＆lt; 9＆amp;＆amp;小时> 18：（或其他）

Calendar currentTime = Calendar.getInstance();
int hour  = currentTime.get(Calendar.HOUR_OF_DAY);

你只需要一个日历

Answer 3

除了您使用的Calendar之外，另一个简单的方法是：

private boolean inRange(Date now) throws ParseException {
    final Date start = new SimpleDateFormat("HH.mm.ss").parse("09.00.00");
    final Date end = new SimpleDateFormat("HH.mm.ss").parse("18.00.00");
    return now.after(start)&& now.before(end);
}

您也可以使用Calendar的before()和after()。

检查java中的时间间隔

3 个答案: