Java.sql.Time not working correctly

Question

Hi guys,
I have the following code which is used to put clients session data in my database.
long logged_in_time = p.getCreatedTime();
            long logged_out_time = System.currentTimeMillis();
            long duration = logged_out_time - logged_in_time;
            System.out.println("LOGGED IN: " + logged_in_time);
            System.out.println("LOGGED OUT: " + logged_out_time);
            System.out.println("DURATION: " + duration);
            System.out.println("DURATION TIME: " + new Time(duration));and this is the result:
LOGGED IN: 1141394617474
LOGGED OUT: 1141394638634
DURATION: 21160
DURATION TIME: 01:00:21
Does anyone know why java.sql.Time adds an hour? The duration in milliseconds equals 21 seconds but when I constuct the Time obj I get 1 hour 21 seconds.
Any help would be great.
Alex

Answer 1

Probably because your default timezone is not GMT, but GMT+1 (e.g. CET.)
The java.util.Date (and subclasses) wraps a long value representing the number of miliseconds elapsed since January 1, 1970, 00:00:00 GMT.
As a consequence a new Date(0) will represent the date above, which is equivalent to January 1, 1970, 01:00:00 CET.
You might use a DateFormat and specify the TimeZone.
Example:        Time time = new Time(21160);
        DateFormat format = DateFormat.getTimeInstance();
        format.setTimeZone(TimeZone.getTimeZone("CET"));
        System.out.println(format.format(time));
        format.setTimeZone(TimeZone.getTimeZone("GMT"));
        System.out.println(format.format(time));Will output:
01:00:21
00:00:21