US timezone changes Mar 2007

hcclnoodles · #1 (**permalink**) 03-01-2007

Hi

As per Suns guide, I have installed the 2 patches that are required to prepare for the US DST change. The first patch updates the zoneinfo database in /usr/share/lib/zoneinfo and I can test that the patch has worked by running the following command

zdump –v US/Eastern | grep 2007

The second patch is a patch that makes changes to the libc library for POSIX based timezone stuff. Which I have applied and rebooted

My question , How do I test that the libc/POSIX patch has worked???? …. What command can I use to see if the date has changed ? As I say testing the zoneinfo patch is easy…but this one has me stumped

Any help would be greatly appreciated

Cheers
Gary

Perderabo · #2 (**permalink**) 03-01-2007

See Understanding Unix Timekeeping which has a perl script that I used for testing.

dsbeerf · #3 (**permalink**) 03-02-2007

Quote:

Originally Posted by Perderabo

See Understanding Unix Timekeeping which has a perl script that I used for testing.

I assume you find some 'off time', or a non-production machine and actually set the system clock to some time just before the time change is suposed to take place (after disabling cron). THEN watch it change.

Also, With Solaris (and lots of other systems), JAVA has it's OWN timezone files that need changing (patching) ! Sun has a 'tzupdater<xxx>.zip' on it's site.

Oh, I forgot ! That's some SERIOUSLY GOOD info, and a really cool testing script !!

RTM · #4 (**permalink**) 03-09-2007

And I assume all the Solaris folks are busy updating for the latest BUG found in Java - Bug ID 6466476. Read that bug and 6530336 for info.

Here is the info from 6530336 (as of this posting):

Quote:

Update Date: Thu Mar 08 00:00:00 MST 2007

Bug ID: 6530336

Synopsis: (tz) CRITICAL DST bug in latest jdk releases

Category: java

Subcategory: classes_text

State: 8-Fix Available

Description:

FULL PRODUCT VERSION :
All current versions (1.4.2_13, 1.5.0_11, 1.6)

ADDITIONAL OS VERSION INFORMATION :
Anything

A DESCRIPTION OF THE PROBLEM :
The recent change to the definition of EST timezone to remove DST awareness has broken basic functionality in date handling.

The problem is very simple. The DateFormat parser uses the contents of String zoneStrings[][] in class DateFormatSymbols to identify the timezone based on the zone value in the input date string.

The zoneStrings[][] array defines "EST" before "America/New_York" so sets the timezone for the parser to the now non-DST aware "EST" zone.

This is a very very serious problem.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Compile and run the test code below as shown.
First run as java -Duser.timezone=America/New_York Moh

and the output is correct: Wed Jun 06 14:00:00 EDT 2007

Then run as java -Duser.timezone=America/Los_Angeles Moh

and the output is wrong: Wed Jun 06 12:00:00 PDT 2007

The correct output would be 11:00:00 PDT 2007.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
In the test case when in the Los Angeles time zone I expect the time to be 11:00:00 PDT but it wrongly displays 12:00:00 PDT.
ACTUAL -
As above.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.text.*;
import java.util.*;

public class Moh {
public static void main(String[] args) throws Exception {
SimpleDateFormat timestampFormatWithZone = new SimpleDateFormat("yyyy-MM-dd HH:mm zzz");
Date date = timestampFormatWithZone.parse("2007-06-06 14:00 EDT");
// Calendar calendar = timestampFormatWithZone.getCalendar();
System.out.println(date);
}
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :This is a very serious problem which has required us to scramble. We are actively deleting the "EST" file from jre/lib/zi to restore prior behaviour, and particularly to ensure that date parsing works correctly.

Date Modified: 2007-03-02 09:25:08 GMT+00:00

Work Around:

Please remove <JDK_HOME>/jre/zi/EST (or <JRE_HOME>/lib/zi/EST). This will enable the old EST to America/New_York mapping.

Date Modified: 2007-03-02 13:17:00 GMT+00:00

Suggested Fix:

Evaluation:

Fixed by patch:

Integrated in Build:

Duplicate of:

Related Change Request(s):

6466476

Date Modified: 2007-03-08 20:00:29 GMT+00:00

sandeepkv · #5 (**permalink**) 03-10-2007

Hi hcclnoodles,

Can u say what are the two patches that u have updated. what guidde did u refer for this

thank u

Perderabo · #6 (**permalink**) 03-10-2007

Quote:

Originally Posted by sandeepkv

Hi hcclnoodles,

Can u say what are the two patches that u have updated. what guidde did u refer for this

thank u

There is a link to our search function on every page. I put in "dst patch", clicked around the results a little and wound up on this page: http://sunsolve.sun.com/search/docum...=1-26-102775-1

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