Change Time zone without change the date format

Question

I have date format like "EEE, dd MMM yyyy HH:mm:ss Z" , and the date is

String date = "Tue, 14 Aug 2012 07:26:33 +0000";

How to change to +0700 time zone without change the date format?

This is what I try

String sDate = null;
Date date = null;
try {
    sDate = "Tue, 14 Aug 2012 07:26:33 +0000";
    SimpleDateFormat curFormater = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss Z");
    curFormater.setTimeZone(TimeZone.getTimeZone("GMT"));
    try {
        date = curFormater.parse(sDate);
    } catch (ParseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
} catch (DropboxException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}
lastUpdate.setText("Last Update : " + date.toString());

but the result is Tue Aug 14 14:26:33 ICT 2012

Answer 1

You're nearly there, you've parsed the date correctly, but you're relying on the default toString() instead of the format you've already created.

Try this instead for the last line:

lastUpdate.setText(curFormater.format(date));

Answer 2

Alternatively, if you want to add a manual number of hours, you could do it something like this:

static final Long oneHourInMilliseconds = new Long(3600000);
static final DateFormat d = new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss Z");

public static Long addHours(Date time, int hours)
{
    return time.getTime() + (hours * oneHourInMilliseconds);
}

public static void main(String[] args) throws ParseException
{
    String dateAsString = "Tue, 14 Aug 2012 07:26:33 +0000";
    Date before = d.parse(dateAsString);
    Date after = new Date(addHours(before, 7));
    System.out.println("Before: " + before + ". After: " + after);
}

Answer 3

date -d在Unix中适用于此。