Question

I have a timestamp in milliseconds that is 1349557200000. How can I check that it occurs at midnight at my current time zone?

The best I’ve come up with is something like:

Calendar mycal = Calendar.getInstance();
Integer offset = (mycal.get(Calendar.ZONE_OFFSET) + mycal.get(Calendar.DST_OFFSET)) * (60 * 1000);
Boolean isAtMidnight = 1349557200000L % (24L * 60L * 60L * 1000L)) == (long) offset ? true : false;

This looks a tad complicated. I was wondering if there are any shortcut methods that I might be missing. Thanks.

Answer 1

Calendar cal = Calendar.getInstance();
cal.setTimeInMillis(milliseconds);
return cal.get(Calendar.HOUR_OF_DAY) == 0
       && cal.get(Calendar.MINUTE) == 0
       && cal.get(Calendar.SECOND) == 0
       && cal.get(Calendar.MILLISECOND) == 0;