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Date/Calendar confusion

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Subject	Date/Calendar confusion
From	Ulrich Scholz <d7@thispla.net>
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Dear all,

have a look at the function below (Java 5).  The first result is 0 as expected. But why is the second one different?

Thanks, Ulrich
 

private static void testDate() throws ParseException
    {
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS");
        TimeZone timeZone = TimeZone.getTimeZone("GMT");
        timeZone.setRawOffset(0); // get GMT time zone for sure
        dateFormat.setTimeZone(timeZone);

        Calendar calendar1 = Calendar.getInstance(timeZone, Locale.US);
        Date date1 = dateFormat.parse("1970-01-01T00:00:00.000");
        calendar1.setTime(date1);
        System.out.println(calendar1.getTimeInMillis()); // is 0

        Calendar calendar2 = Calendar.getInstance(timeZone, Locale.US);
        Date date2 = dateFormat.parse("0000-00-00T00:00:00.000");
        calendar2.setTime(date2);

        // adjust for the epoch 01.01.1970
        //
        calendar2.set(Calendar.YEAR, calendar2.get(Calendar.YEAR) + 1970);
        calendar2.set(Calendar.MONTH, calendar2.get(Calendar.MONTH) + 1);
        calendar2.set(Calendar.DAY_OF_MONTH, calendar2.get(Calendar.DAY_OF_MONTH) + 1);

        System.out.println(calendar2.getTimeInMillis()); // should be 0 but is -124335907200000
    }

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Date/Calendar confusion Ulrich Scholz <d7@thispla.net> - 2012-09-06 01:03 -0700
  Re: Date/Calendar confusion nogales <nogales.manuel@gmail.com> - 2012-09-06 02:29 -0700
  Re: Date/Calendar confusion Lew <lewbloch@gmail.com> - 2012-09-06 10:21 -0700
  Re: Date/Calendar confusion "John B. Matthews" <nospam@nospam.invalid> - 2012-09-06 20:53 -0400
    Re: Date/Calendar confusion Lew <lewbloch@gmail.com> - 2012-09-07 11:01 -0700
      Re: Date/Calendar confusion "John B. Matthews" <nospam@nospam.invalid> - 2012-09-07 21:02 -0400
        Re: Date/Calendar confusion Lew <lewbloch@gmail.com> - 2012-09-07 18:44 -0700
          Re: Date/Calendar confusion "John B. Matthews" <nospam@nospam.invalid> - 2012-09-08 09:12 -0400
            Re: Date/Calendar confusion Lew <lewbloch@gmail.com> - 2012-09-08 16:51 -0700

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