Convert UTC timestamp to local timestamp with DST

Question

Here is my code to do this. My question is how does android(any other system take care of DST internally). DST rules can change. Or is it a too corner case to be of any real concern.

public long getLocalTimeFromUTCTime(long utcTime)
{
    Time time = new Time();
    time.set(utcTime);
    TimeZone localTimezone = TimeZone.getDefault();
    time.switchTimezone(localTimezone.getID());
    time.normalize(false);
    return time.toMillis(false);
}

Answer 1

As suggested here, this seems to have done the trick:

SimpleDateFormat dateTimeFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSSZ");
String date="2012-10-03T22:00:00.000+0000";
try {
    System.out.println(dateTimeFormat.getTimeZone().getDisplayName());
    System.out.println("Today : "+new Date().toString()+ ", Timezone Offset :" +
            +(new Date()).getTimezoneOffset());
    System.out.println("Parsed Date : "+
            dateTimeFormat.parse(date).toString()
            + ", Timezone Offset : "
            +dateTimeFormat.parse(date).getTimezoneOffset());           
} catch (ParseException e) {            
    e.printStackTrace();
}

More specifically, you should have a look at getTimezoneOffset().