how to convert given offset time(in seconds) to Format like +hh:mm in java?

Question

i want to give support of timezone..for that am storing the value of date in the database with the UTC Time and then i am converting the time depends on the user local time zone..for that am using this line in my database query

CONVERT_TZ(modifiedtime,'+00:00','+05:30') this will give me local time zone for the Indian Standard time...but my question is i have only offset in econds and ther id for the particular user..

so is ther anyway that i can convert offset to format like +05:30 or say +04.00 ,+04.30.. can anyone give me proper solution that if i can convert this offset which is given in seconds to format like +hh:mm so i can directly give it to query...

Am using liferay 6.1 portal in that i have created My custom portlet..so i need to make it this code in java language...so please can any one guide me?

Answer 1

you could try coding your own conversion or try this:

  long offset = 19800; //offset IST (seconds)
  long time = TimeUnit.SECONDS.toMinutes(offset); //or offset/60
  long hour = time / 60;
  long min = Math.abs(time % 60);
  String hrStr = "";
  if (hour > 0 && hour < 10) {
    hrStr = "+0" + String.valueOf(hour);
  } else if (hour >= 10) {
    hrStr = "+" + String.valueOf(hour);
  } else if (hour < 0 && hour > -10) {
    hrStr = "-0" + String.valueOf(hour).substring(1);
  } else {
    hrStr = String.valueOf(hour);
  }
  String minStr = String.valueOf(min);
  if (min < 10) {
    minStr = "0" + (time % 60);
  }
  String timeStr = hrStr + ":" + minStr;
  System.out.println(timeStr);

Answer 2

The following might be a little shorter and convienient

private static SimpleDateFormat plus = new SimpleDateFormat("+hh:mm");

private static SimpleDateFormat minus = new SimpleDateFormat("-hh:mm");

private static String getTimeCode(int seconds) {
    SimpleDateFormat simpleDateFormat = (seconds < 0) ? minus : plus;
    if (seconds < 0) seconds = 12 * 3600 - seconds;
    simpleDateFormat.setTimeZone(TimeZone.getTimeZone("UTC"));
    return simpleDateFormat.format(new Date(seconds * 1000));
}

int seconds = 5 * 3600 + 30 * 60;
String format = getTime(seconds); //+05:30
format = getTime(-1 * seconds);   //-05:30

Above code may not apply all coding standards, but is short for SO