How to convert a local date to GMT

Question

Calendar cal = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
java.util.Date fromDate = cal.getTime();
System.out.println(fromDate);

The above code doesn't print the date in GMT, but rather prints in the local timezone. How do I get a GMT equivalent date from the current date (assuming that the program can run in Japan or SFO)

Subhrajyoti Majumder · Accepted Answer · 2013-09-30T06:21:36.800

How about this -

public static void main(String[] args) throws IOException {
    Test test=new Test();
    Date fromDate = Calendar.getInstance().getTime();
    System.out.println("UTC Time - "+fromDate);
    System.out.println("GMT Time - "+test.cvtToGmt(fromDate));
}
private  Date cvtToGmt( Date date ){
    TimeZone tz = TimeZone.getDefault();
    Date ret = new Date( date.getTime() - tz.getRawOffset() );

    // if we are now in DST, back off by the delta.  Note that we are checking the GMT date, this is the KEY.
    if ( tz.inDaylightTime( ret )){
        Date dstDate = new Date( ret.getTime() - tz.getDSTSavings() );

        // check to make sure we have not crossed back into standard time
        // this happens when we are on the cusp of DST (7pm the day before the change for PDT)
        if ( tz.inDaylightTime( dstDate )){
            ret = dstDate;
        }
     }
     return ret;
}

Test Result :
UTC Time - Tue May 15 16:24:14 IST 2012
GMT Time - Tue May 15 10:54:14 IST 2012

score 18 · Answer 2 · answered May 15 '12 at 10:50

18

DateFormat gmtFormat = new SimpleDateFormat();
TimeZone gmtTime = TimeZone.getTimeZone("GMT");
gmtFormat.setTimeZone(gmtTime);
System.out.println("Current DateTime in GMT : " + gmtFormat.format(new Date()));

More generally you can convert to any (valid) time zone this way

See

DateFormat

answered May 15 '12 at 10:50

jmj

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2

gmtFormat.format(new Date()) return type is String.but i want to date. – May 15 '12 at 11:09
1

You can `parse()` that String to create Date instance – jmj May 15 '12 at 11:26
As soon as you parse, it makes it back to your local timezone format. In my case, it converts it back to IST. How to keep it in GMT – Hitesh Kumar Jul 04 '17 at 09:25

score 2 · Answer 3 · answered May 15 '12 at 10:55

2

Like this SimpleDateFormat dateFormatGmt = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss"); dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT")); ?

answered May 15 '12 at 10:55

RMartins

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How to convert a local date to GMT

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