How do I convert seconds into accumulated hhh:mm:ss?

Question

I want to convert an elapsed amount of accumulated seconds into hours:minutes:seconds. For example

93599 seconds to:

25:59:59

How can I do that? (Note: 24h should not wrap to 0h)

Answer 1

The modulus operator % is useful here. Something like this would work well

public static void convertTime(int seconds) {
    int secs = seconds % 60;
    int mins = (seconds / 60) % 60;
    int hours = (seconds / 60) / 60;
    System.out.printf("%d:%d:%d", hours, mins, secs);
}

Answer 2

Java 8 provides the java.time.Duration class for expressing amounts of time. You can use Duration#ofSeconds(long) to build an instance from an amount of seconds.

Duration ellapsed = Duration.ofSeconds(93599);

However, the default toString format looks like

PT25H59M59S

which isn't what you want. You can do the math yourself (with the various toMinutes, toHours, etc.) to convert it to the format you want. An example is given here.

Answer 3

hours = 93599 / 3600. Use integer arithmetic to force a truncation.

Then subtract hours * 3600 from 93599. Call that foo. Or compute 93599 % 3600.

minutes = foo / 60. Use integer arithmetic.

Subtract minutes * 60 from foo. Call that bar. Or compute foo % 60.

bar is the remaining seconds.

Answer 4

Copy and use this Class:

public class AccumulatedTimeFormat extends Format {

@Override
public StringBuffer format(Object obj, StringBuffer toAppendTo, FieldPosition pos) {
    Long totalSeconds;

    if(obj instanceof Byte) {
        totalSeconds=((Byte)obj).longValue();
    } else if(obj instanceof Short) {
        totalSeconds=((Short)obj).longValue();
    } else if(obj instanceof Integer) {
        totalSeconds=((Integer)obj).longValue();
    } else if(obj instanceof Long) {
        totalSeconds=((Long)obj);
    } else {
        throw new IllegalArgumentException("Cannot format given Object as an accumulated-time String!");
    }

    long ss = Math.abs(totalSeconds) % 60;
    long mm = (Math.abs(totalSeconds) / 60) % 60;
    long h = (Math.abs(totalSeconds) / 60) / 60;

    if(totalSeconds<0) {
        toAppendTo.append('-');
    }
    toAppendTo.append(String.format("%d:%02d:%02d", h, mm, ss));

    return toAppendTo;
}

@Override
public Object parseObject(String source, ParsePosition pos) {
    //TODO Implement if needed!
    return null;
}

}

Like this:

System.out.println((new AccumulatedTimeFormat()).format(93599));

Which prints:

25:59:59