Java Date Conversion from Millisecond time -

i trying calculate offset time given date. date string , parse it, , have offset in milliseconds. example

date: 2015-08-18 00:00:00

offset time: 2678400000, when applied date, equals 2015-09-18 00:00:00, 31 days later.

my goal store each of offsets (years/months/days/hours/minutes/seconds) in array, can use later. when run calculation using calendar class, i'm getting hours reason when called offsetconverter(2678400000)

output: 0 years 0 months 31 days 19 hours 0 minutes 0 seconds  

here code found , modified link best way convert milliseconds number of years, months , days

    public static int[] offsetconverter(long offset) {     int[] delay =  new int[6];     //delay 0-3 = years/months/days/seconds      calendar c = calendar.getinstance();      c.settimeinmillis(offset);     delay[0] = c.get(calendar.year) - 1970;     delay[1] = c.get(calendar.month);     delay[2] = c.get(calendar.day_of_month);     delay[3] = c.get(calendar.hour_of_day);     delay[4] = c.get(calendar.minute);     delay[5] = c.get(calendar.second);      (int = 0; i< delay.length; i++)         system.out.print(delay[i] + " ");     system.out.println();     return delay; } 

if sees i'm doing wrong or has simpler way appreciate help. thanks!

milliseconds date#gettime() arrive in utc timezone, instantiate calendar default timezone, local. adds hours result.

to solve issue, create calendar instance using utc timezone:

calendar c = calendar.getinstance(timezone.gettimezone("utc"));