Format seconds integer to time in Groovy

Question

I have a variable containing time in seconds like 990 which would be 16 minutes 30 seconds. How do I convert this to time 00:16:30 in Groovy?

Along the same lines, how do I convert it the other way around?

Answer 1

String timestamp = 
      new GregorianCalendar( 0, 0, 0, 0, 0, 990, 0 ).time.format( 'HH:mm:ss' )

From duration to seconds:

long seconds = ( Date.parse( 'HH:mm:ss', '00:16:30' ).time - 
                 Date.parse( 'HH:mm:ss', '00:00:00' ).time ) / 1000

Answer 2

Take a look at this little creature below. Groovy's sprintf() and a bit of calculations. Unfortunately it doesn't look smart ;)

def seconds = 990
assert sprintf '%02d:%02d:%02d', (int) (seconds / 3600), (int) (seconds % 3600 / 60), (int) (seconds % 60) == '00:16:30'

Answer 3

Here You go:

def c = Calendar.instance
c.clear()
c.set(Calendar.SECOND, 990)

assert c.format('HH:mm:ss') == '00:16:30'

I suppose it might be done a bit smarter in plain groovy ;)

Once again, whole solution:

Calendar.instance.with {
    clear()
    set(Calendar.SECOND, 990)

    assert format('HH:mm:ss') == '00:16:30'

    def time = '00:16:30'.split(':')*.toInteger()
    clear()
    set(Calendar.MINUTE, time[1])
    set(Calendar.SECOND, time[2])
    assert (timeInMillis - Date.parse('HH:mm:ss', '00:00:00').time)/1000 == 990
}