Date/Time display problem

[Steven Woodford]

I am having a problem displaying small time periods using the Date class. I'm quite new to Java (and this forum) so i'm hoping there is an easy way around this that i just haven't learned yet.
Here goes:
This code has been tested on Windows NT 2K and XP with the same results.
I am trying to display a time period stored in milliseconds as a long using code similar to this.
long timePeriod = 300000L;
System.out.println(new Date(timePeriod));
I would expect this to display...
Thu Jan 01 00:05:00 GMT 1970 (i am ignoring the date, its just the time i'm looking for)
... but instead it displays
Thu Jan 01 01:05:00 GMT 1970
I have found that if i un-tick the "Automatically adjust clock for daylight saving changes" option in time zone settings, the problem goes away - however i need to have this option on.
I would be grateful of any light you could shed on this as it has got me feeling quite
Thanks in advance,
Ste

[Greg Charles]

Dates print by default in your local time zone. You show GMT prints out, but I bet it's really whatever time zone you're in, right? Anyway try this:

import java.util.Date;
import java.util.TimeZone;
import java.text.DateFormat;
public class TestDate
{
    public static void main(String[] args)
    {
        Date date = new Date(300000L);
        DateFormat formatter = DateFormat.getTimeInstance();;
        formatter.setTimeZone(TimeZone.getTimeZone("GMT"));
        System.out.println(formatter.format(date));
    }
}

BTW, 5 hours in miliseconds in 18,000,000, not 300,000. It's a good idea to show things like that explicitly: 5L * 60 * 60 * 1000. It makes it clearer what you're doing, and you don't make computation errors. The compiler will do the math, so you don't even hurt runtime performance.

[Layne Lund]

Unless I am mistaken, the output says 5 minutes, not 5 hours...

[Steven Woodford]

Thanks for your suggestions, but I don't think I have explained my problem very well.
I am using a timer object to schedule events. The timer has a user-defined interval anywhere between 1 minute and a couple of hours. I want to display the time until the next timer event triggers.
The way I am calculating the time out, which seems to be correct, is as follows (all values are in long):
timeOut = timerInterval - (currentTime - timeOfLastEvent)
The value of timeOut is what i am putting into a date formatter to display the time out, but when I have the "adjust clock for daylight saving changes" option ticked I get an extra hour added onto the time out I have calculated.
Thanks again.

[Steven Woodford]

Sorry, not explained fully again. The extra hour seems to be added on by the date formatter (the value of timeOut is correct)