GMT to EDT

use dateformater,

convert your GTM date to date string in GMT, for e.g., 01 JAN 2010 01:01:01 GMT
and then use below formatter to parse it to Date back, before doing so, set the system default timezone to EST/EDT
SimpleDateFormat sdf = new SimpleDateFormat( "dd MMM yyyy HH:mm:ss z" ) ;

btw, prefer timezones using the city names to three-letter codes

Is this correct

Date recDateGMT = idfTimeRecieveDate.getDate();
String recDateStr = recDateGMT.toGMTString();
TimeZone edtTimeZone = TimeZone.getTimeZone("EDT");

DateFormat df = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss");
df.setTimeZone(edtTimeZone);
String edtDateStr = df.format(recDateGMT);

Yes, that looks good although i'm not sure that you need to convert recDateGMT to a String first

Thank you.
I executed the following code

 It printed the following logs
=================GMT Date===================Fri Mar 28 19:08:46 EDT 2008
 ==================EDT Date =========03/28/2008 23:08:46
The logs suggest that the method which was supposed to return GMT time is returning EDT time. If it is really returning EDT time then why does the time change when the timezone is set to EDT (that is in the second print statement)?

Date recDateGMT = getGMTTime();
System.out.println("=================GMT Date==================="+recDateGMT.toString()); 
TimeZone edtTimeZone = TimeZone.getTimeZone("EDT"); 
DateFormat df = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss"); 
df.setTimeZone(edtTimeZone); 
String edtDateStr = df.format(recDateGMT); 
logger.debug("==================EDT Date ========="+edtDateStr);

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>>The logs suggest that the method which was supposed to return GMT time is returning EDT time.

That's because it's using a default formatter, which looks like it's set to EDT already

If you want it to print GMT without fail, you must use the same method, the difference being with a GMT TimeZone

Thank you.
But why does the time change when formatter is explicitly set to EDT?

>>If you want it to print GMT without fail, you must use the same method, the difference being with a GMT TimeZone
 
I just want to get the correct EDT Timezone.

Probably because the method getGMTTime() (which you don't show) returns a different Date

>>Probably because the method getGMTTime() (which you don't show) returns a different Date

Ignore that bizarre comment.

>>But why does the time change when formatter is explicitly set to EDT?

Why would it *not* do if you're using different time zones?

>>Probably because the method getGMTTime() (which you don't show) returns a different Date

But if it returns a time which is already EDT time (as suggested by first print statement) then why does setting the timezone explicitly to EDT changes the time.

>>But if it returns a time which is already EDT time  ...

(See above)

Yes, EDT is not actually a TZ available in itself in my system. EST is the principal one

This question brings up some interesting issues IMO, but for the time being, the below shows some of the things i mentioned above:

import java.util.*;
import java.text.*;

public class GmtEdt {
    public static void main(String[] args) {
	Date d = java.sql.Timestamp.valueOf("2008-03-28 23:08:46");
	TimeZone edt = TimeZone.getTimeZone("America/New_York");
	Calendar cal = Calendar.getInstance();
	cal.setTimeZone(edt);
	cal.setTime(d);
	TimeZone gmt = TimeZone.getTimeZone("UTC");
	DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z");
	df.setTimeZone(gmt);
	System.out.println(df.format(d));
	df.setTimeZone(edt);
	System.out.println(df.format(d));
	System.out.printf("Was date %s actually in dst? %b\n", df.format(d), (cal.get(Calendar.DST_OFFSET) != 0));
    }
}

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:-)

see the following to determine the available timezones

http://helpdesk.objects.com.au/java/can-i-find-all-available-timezones-for-a-country