JAVA time rounding issue

Question

Hope you can help :-)

Struggling with an unusual rounding issue...

If time is "7:35 AM" the time should be "8:00 AM" - rounded to the nearest 30 minutes going forward...

If time is "7:20 AM" the time should be "7:30 AM"

Any ideas would be appreciated.

I have this but it rounds forwards and backwards. Only need it to go forward:

private DateTime roundDate(final DateTime dateTime, final int minutes) {
    if (minutes < 1 || 60 % minutes != 0) 
    {
        throw new IllegalArgumentException("minutes must be a factor of 60");
    }

    final DateTime hour = dateTime.hourOfDay().roundFloorCopy();
    final long millisSinceHour = new Duration(hour, dateTime).getMillis();
    final int roundedMinutes = ((int) Math.round(millisSinceHour / 60000.0 / minutes)) * minutes;

    System.out.println(hour.plusMinutes(roundedMinutes));

    return hour.plusMinutes(roundedMinutes);
}

Do you have any code or you just asking for ideas? if so a simple if else would do this easily — dave, Oct 22 '14 at 21:35

score 0 · Accepted Answer · edited May 23 '17 at 12:20

0

I would suggest you use the Joda time library. In addition to the cool date helpers it provides, you should find here a snipplet with code that does almost what you need.

edited May 23 '17 at 12:20

Community

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answered Oct 22 '14 at 21:57

Guy Bouallet

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Thanks for the response but my method above does the same. I need it to round forward ONLY... – Amstel Bytes Oct 22 '14 at 22:11
Oh sorry. I didn't see the sample you posted in the meanwhile. I would suggest you add 30 mn to hour if millisSinceHour is less than 30 * 60000 – Guy Bouallet Oct 22 '14 at 22:33
And add 60 mn if it is greater. – Guy Bouallet Oct 22 '14 at 22:35

JAVA time rounding issue

1 Answers1