How can I get the current date and time in UTC or

Question

When I create a new Date object, it is initialized to the current time but in the local timezone. How can I get the current date and time in GMT?

Answer 1

If you're using joda time and want the current time in milliseconds without your local offset you can use this:

long instant = DateTimeZone.UTC.getMillisKeepLocal(DateTimeZone.getDefault(), System.currentTimeMillis());

Answer 2

With:

Calendar cal = Calendar.getInstance();

Then cal have the current date and time.
You also could get the current Date and Time for timezone with:

Calendar cal2 = Calendar.getInstance(TimeZone.getTimeZone("GMT-2"));

You could ask cal.get(Calendar.DATE); or other Calendar constant about others details.
Date and Timestamp are deprecated in Java. Calendar class it isn't.

Answer 3

java.util.Date has no specific time zone, although its value is most commonly thought of in relation to UTC. What makes you think it's in local time?

To be precise: the value within a java.util.Date is the number of milliseconds since the Unix epoch, which occurred at midnight January 1st 1970, UTC. The same epoch could also be described in other time zones, but the traditional description is in terms of UTC. As it's a number of milliseconds since a fixed epoch, the value within java.util.Date is the same around the world at any particular instant, regardless of local time zone.

I suspect the problem is that you're displaying it via an instance of Calendar which uses the local timezone, or possibly using Date.toString() which also uses the local timezone, or a SimpleDateFormat instance, which, by default, also uses local timezone.

If this isn't the problem, please post some sample code.

I would, however, recommend that you use Joda-Time anyway, which offers a much clearer API.

Answer 4

Jon Skeet asks:

@Downvoter: Care to comment? What exactly is incorrect in my answer? – Jon Skeet Oct 26 '09 at 21:09

I am not the Downvoter, but here is what seems to be incorrect in that answer. You said:

java.util.Date is always in UTC. What makes you think it's in local time? I suspect the problem is that you're displaying it via an instance of Calendar which uses the local timezone, or possibly using Date.toString() which also uses the local timezone.

However, the code:

System.out.println(new java.util.Date().getHours() + " hours");

gives the local hours, not GMT (UTC hours), using no Calendar and no SimpleDateFormat at all.

That is why is seems something is incorrect.

Putting together the responses, the code:

System.out.println(Calendar.getInstance(TimeZone.getTimeZone("GMT"))
                           .get(Calendar.HOUR_OF_DAY) + " Hours");

shows the GMT hours instead of the local hours -- note that getTime.getHours() is missing because that would create a Date() object, which theoretically stores the date in GMT, but gives back the hours in the local time zone.

Answer 5

This worked for me, returns the timestamp in GMT!

    Date currDate;
    SimpleDateFormat dateFormatGmt = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss");
    dateFormatGmt.setTimeZone(TimeZone.getTimeZone("GMT"));
    SimpleDateFormat dateFormatLocal = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss");

    long currTime = 0;
    try {

        currDate = dateFormatLocal.parse( dateFormatGmt.format(new Date()) );
        currTime = currDate.getTime();
    } catch (ParseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

Answer 6

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

//Local time zone   
SimpleDateFormat dateFormatLocal = new SimpleDateFormat("yyyy-MMM-dd HH:mm:ss");

//Time in GMT
return dateFormatLocal.parse( dateFormatGmt.format(new Date()) );