JDK-4813746 : The java.util.TimeZone ID "Etc/GMT+offset" Gives Incorrect TimeZone
  • Type: Bug
  • Component: core-libs
  • Sub-Component: java.util:i18n
  • Affected Version: 1.4.1
  • Priority: P4
  • Status: Closed
  • Resolution: Not an Issue
  • OS: windows_2000
  • CPU: x86
  • Submitted: 2003-02-05
  • Updated: 2003-02-06
  • Resolved: 2003-02-06
Related Reports
Relates :  
Description

Name: nt126004			Date: 02/05/2003


FULL PRODUCT VERSION :
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1_01-b01)
Java HotSpot(TM) Client VM (build 1.4.1_01-b01, mixed mode)

FULL OPERATING SYSTEM VERSION :
Microsoft Windows 2000 [Version 5.00.2195]

A DESCRIPTION OF THE PROBLEM :
With the lines below the ID "Etc/GMT-8" is treated as
GMT+8:00, and ID "Etc/GMT+8" is treated as GMT-8:00.   This
seems erroneous or at least misleading.

import java.util.*;

public final class EtcTimeZone{
public static void main(String[] args) throws
java.lang.Exception{
String[] ids =
java.util.TimeZone.getAvailableIDs(-8*60*60*1000);
for(int i=0;i<ids.length;i++){
	System.out.println(ids[i]);
}
// In the result there is the ID "Etc/GMT+8"
 ids = java.util.TimeZone.getAvailableIDs(8*60*60*1000);
for(int i=0;i<ids.length;i++){
	System.out.println(ids[i]);
}
// In the result there is the ID "Etc/GMT-8"

System.out.println();
java.util.TimeZone zone =
java.util.TimeZone.getTimeZone("Etc/GMT-8");
System.out.println(zone.getDisplayName());//result is GMT+8


zone = java.util.TimeZone.getTimeZone("Etc/GMT+8");
System.out.println(zone.getDisplayName());//result is GMT-8

}
}



STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Straightforward and seems there is no need for steps of
reproducing.


EXPECTED VERSUS ACTUAL BEHAVIOR :
"Etc/GMT-8"  ->  GMT-8:00
"Etc/GMT+8" ->  GMT+8:00

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
//The following is the reproduction of the code give above:

import java.util.*;

public final class EtcTimeZone{
public static void main(String[] args) throws java.lang.Exception{
String[] ids = java.util.TimeZone.getAvailableIDs(-8*60*60*1000);
for(int i=0;i<ids.length;i++){
	System.out.println(ids[i]);
}
// In the result there is the ID "Etc/GMT+8"
 ids = java.util.TimeZone.getAvailableIDs(8*60*60*1000);
for(int i=0;i<ids.length;i++){
	System.out.println(ids[i]);
}
// In the result there is the ID "Etc/GMT-8"

System.out.println();
System.out.println("getting TimeZone for \"Etc/GMT-8\"");
java.util.TimeZone zone = java.util.TimeZone.getTimeZone("Etc/GMT-8");
System.out.println(zone.getDisplayName());//result is GMT+8

System.out.println("getting TimeZone for \"Etc/GMT+8\"");
zone = java.util.TimeZone.getTimeZone("Etc/GMT+8");
System.out.println(zone.getDisplayName());//result is GMT-8

}
}


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

CUSTOMER WORKAROUND :
Actually I do not use these ID's.
(Review ID: 180806) 
======================================================================

Comments
EVALUATION Java follows the definitions by the Olson public source. The definitions of Etc/GMT+-* are as follows: # @(#)etcetera 7.11 # These entries are mostly present for historical reasons, so that # people in areas not otherwise covered by the tz files could "zic -l" # to a time zone that was right for their area. These days, the # tz files cover almost all the inhabited world, so there's little # need now for the entries that are not on UTC. Zone Etc/GMT 0 - GMT Zone Etc/UTC 0 - UTC Zone Etc/UCT 0 - UCT # The following link uses older naming conventions, # but it belongs here, not in the file `backward', # as functions like gmtime load the "GMT" file to handle leap seconds properly. # We want this to work even on installations that omit the other older names. Link Etc/GMT GMT Link Etc/UTC Etc/Universal Link Etc/UTC Etc/Zulu Link Etc/GMT Etc/Greenwich Link Etc/GMT Etc/GMT-0 Link Etc/GMT Etc/GMT+0 Link Etc/GMT Etc/GMT0 # We use POSIX-style signs in the Zone names and the output abbreviations, # even though this is the opposite of what many people expect. # POSIX has positive signs west of Greenwich, but many people expect # positive signs east of Greenwich. For example, TZ='Etc/GMT+4' uses # the abbreviation "GMT+4" and corresponds to 4 hours behind UTC # (i.e. west of Greenwich) even though many people would expect it to # mean 4 hours ahead of UTC (i.e. east of Greenwich). # # In the draft 5 of POSIX 1003.1-200x, the angle bracket notation # (which is not yet supported by the tz code) allows for # TZ='<GMT-4>+4'; if you want time zone abbreviations conforming to # ISO 8601 you can use TZ='<-0400>+4'. Thus the commonly-expected # offset is kept within the angle bracket (and is used for display) # while the POSIX sign is kept outside the angle bracket (and is used # for calculation). # # Do not use a TZ setting like TZ='GMT+4', which is four hours behind # GMT but uses the completely misleading abbreviation "GMT". # Earlier incarnations of this package were not POSIX-compliant, # and had lines such as # Zone GMT-12 -12 - GMT-1200 # We did not want things to change quietly if someone accustomed to the old # way does a # zic -l GMT-12 # so we moved the names into the Etc subdirectory. Zone Etc/GMT-14 14 - GMT-14 # 14 hours ahead of GMT Zone Etc/GMT-13 13 - GMT-13 Zone Etc/GMT-12 12 - GMT-12 Zone Etc/GMT-11 11 - GMT-11 Zone Etc/GMT-10 10 - GMT-10 Zone Etc/GMT-9 9 - GMT-9 Zone Etc/GMT-8 8 - GMT-8 Zone Etc/GMT-7 7 - GMT-7 Zone Etc/GMT-6 6 - GMT-6 Zone Etc/GMT-5 5 - GMT-5 Zone Etc/GMT-4 4 - GMT-4 Zone Etc/GMT-3 3 - GMT-3 Zone Etc/GMT-2 2 - GMT-2 Zone Etc/GMT-1 1 - GMT-1 Zone Etc/GMT+1 -1 - GMT+1 Zone Etc/GMT+2 -2 - GMT+2 Zone Etc/GMT+3 -3 - GMT+3 Zone Etc/GMT+4 -4 - GMT+4 Zone Etc/GMT+5 -5 - GMT+5 Zone Etc/GMT+6 -6 - GMT+6 Zone Etc/GMT+7 -7 - GMT+7 Zone Etc/GMT+8 -8 - GMT+8 Zone Etc/GMT+9 -9 - GMT+9 Zone Etc/GMT+10 -10 - GMT+10 Zone Etc/GMT+11 -11 - GMT+11 Zone Etc/GMT+12 -12 - GMT+12 However, Java uses the real life GMT offset convention for display names rather than the POSIX one (e.g., GMT-8 means 8 hours behind GMT.) By the way, the output as ACTUAL BEHAVIOR in Description is incorrect. EXPECTED VERSUS ACTUAL BEHAVIOR : "Etc/GMT-8" -> GMT-8:00 "Etc/GMT+8" -> GMT+8:00 should be: EXPECTED VERSUS ACTUAL BEHAVIOR : "Etc/GMT-8" -> GMT+08:00 "Etc/GMT+8" -> GMT-08:00 as seen below. America/Dawson America/Ensenada America/Los_Angeles America/Tijuana America/Vancouver America/Whitehorse Canada/Pacific Canada/Yukon Etc/GMT+8 Mexico/BajaNorte PST PST8PDT Pacific/Pitcairn SystemV/PST8 SystemV/PST8PDT US/Pacific US/Pacific-New Antarctica/Casey Asia/Brunei Asia/Chongqing Asia/Chungking Asia/Harbin Asia/Hong_Kong Asia/Irkutsk Asia/Kashgar Asia/Kuala_Lumpur Asia/Kuching Asia/Macao Asia/Macau Asia/Makassar Asia/Manila Asia/Shanghai Asia/Singapore Asia/Taipei Asia/Ujung_Pandang Asia/Ulaanbaatar Asia/Ulan_Bator Asia/Urumqi Australia/Perth Australia/West CTT Etc/GMT-8 Hongkong PRC Singapore GMT+08:00 GMT-08:00 ###@###.### 2003-02-06
2003-02-06