On Wed, 21 Dec 2022 23:21:42 GMT, Ichiroh Takiguchi <itakigu...@openjdk.org>
wrote:
>> test/jdk/java/util/TimeZone/CustomTzIDCheckDST.java may fail at future date.
>> I used following standalone testcase
>>
>> import java.util.Calendar;
>> import java.util.Date;
>> import java.util.SimpleTimeZone;
>>
>> public class CheckDST {
>> private static String CUSTOM_TZ = "MEZ-1MESZ,M3.5.0,M10.5.0";
>> public static void main(String args[]) throws Throwable {
>> runTZTest();
>> }
>>
>> /* TZ code will always be set to "MEZ-1MESZ,M3.5.0,M10.5.0".
>> * This ensures the transition periods for Daylights Savings should be
>> at March's last
>> * Sunday and October's last Sunday.
>> */
>> private static void runTZTest() {
>> Date time = new Date();
>> if (new SimpleTimeZone(3600000, "MEZ-1MESZ", Calendar.MARCH, -1,
>> Calendar.SUNDAY, 0,
>> Calendar.OCTOBER, -1, Calendar.SUNDAY,
>> 0).inDaylightTime(time)) {
>> // We are in Daylight savings period.
>> if (time.toString().endsWith("GMT+02:00 " +
>> Integer.toString(time.getYear() + 1900)))
>> return;
>> } else {
>> if (time.toString().endsWith("GMT+01:00 " +
>> Integer.toString(time.getYear() + 1900)))
>> return;
>> }
>>
>> // Reaching here means time zone did not match up as expected.
>> throw new RuntimeException("Got unexpected timezone information: " +
>> time);
>> }
>> }
>>
>>
>> I tested CheckDST with faketime, then I got following results
>>
>> $ TZ=GMT faketime -m "2023-03-25 22:59:59" env TZ="MEZ-1MESZ,M3.5.0,M10.5.0"
>> $HOME/jdk-21-b02/bin/java CheckDST
>> $ TZ=GMT faketime -m "2023-03-25 23:00:00" env TZ="MEZ-1MESZ,M3.5.0,M10.5.0"
>> $HOME/jdk-21-b02/bin/java CheckDST
>> Exception in thread "main" java.lang.RuntimeException: Got unexpected
>> timezone information: Sun Mar 26 00:00:00 GMT+01:00 2023
>> at CheckDST.runTZTest(CheckDST.java:28)
>> at CheckDST.main(CheckDST.java:8)
>>
>>
>> I assume `TZ=MEZ-1MESZ`refers Europe/Berlin timezone.
>> In this case, `TZ` environment variable should be
>> `MEZ-1MESZ,M3.5.0,M10.5.0/3` (`/3` is missing in testcase)
>>
>> CustomTzIDCheckDST should run with daylight saving time.
>> Add Simulate Southern Hemisphere by `MEZ-1MESZ,M10.5.0,M3.5.0/3`
>>
>> Tested by standalone testcase
>>
>> $ cat CheckDST1.java
>> import java.util.Calendar;
>> import java.util.Date;
>> import java.util.List;
>> import java.util.SimpleTimeZone;
>> import java.util.TimeZone;
>> import java.time.DayOfWeek;
>> import java.time.ZonedDateTime;
>> import java.time.temporal.TemporalAdjusters;
>> public class CheckDST1 {
>> // Northern Hemisphere
>> private static String CUSTOM_TZ = "MEZ-1MESZ,M3.5.0,M10.5.0/3";
>> // Simulate Southern Hemisphere
>> private static String CUSTOM_TZ2 = "MEZ-1MESZ,M10.5.0,M3.5.0/3";
>> public static void main(String args[]) throws Throwable {
>> runTZTest();
>> }
>>
>> /* TZ code will always be set to "MEZ-1MESZ,M3.5.0,M10.5.0/3".
>> * This ensures the transition periods for Daylights Savings should be
>> at March's last
>> * Sunday and October's last Sunday.
>> */
>> private static void runTZTest() {
>> Date time = new Date();
>> String tzStr = System.getenv("TZ");
>> if (tzStr == null)
>> throw new RuntimeException("Got unexpected timezone information:
>> TZ is null");
>> boolean nor = tzStr.matches(".*,M3\..*,M10\..*");
>> TimeZone tz = new SimpleTimeZone(3600000, tzStr,
>> nor ? Calendar.MARCH : Calendar.OCTOBER, -1,
>> Calendar.SUNDAY, 3600000, SimpleTimeZone.UTC_TIME,
>> nor ? Calendar.OCTOBER : Calendar.MARCH, -1,
>> Calendar.SUNDAY, 3600000, SimpleTimeZone.UTC_TIME,
>> 3600000);
>> System.out.println(time);
>> if (tz.inDaylightTime(time)) {
>> // We are in Daylight savings period.
>> if (time.toString().endsWith("GMT+02:00 " +
>> Integer.toString(time.getYear() + 1900)))
>> return;
>> } else {
>> if (time.toString().endsWith("GMT+01:00 " +
>> Integer.toString(time.getYear() + 1900)))
>> return;
>> }
>>
>> // Reaching here means time zone did not match up as expected.
>> throw new RuntimeException("Got unexpected timezone information: " +
>> tzStr + " " + time);
>> }
>>
>> private static ZonedDateTime getLastSundayOfMonth(ZonedDateTime date) {
>> return date.with(TemporalAdjusters.lastInMonth(DayOfWeek.SUNDAY));
>> }
>> }
>>
>>
>> Check Europe/Berlin timezone settings
>>
>> $ zdump -v Europe/Berlin | grep 2023
>> Europe/Berlin Sun Mar 26 00:59:59 2023 UTC = Sun Mar 26 01:59:59 2023 CET
>> isdst=0 gmtoff=3600
>> Europe/Berlin Sun Mar 26 01:00:00 2023 UTC = Sun Mar 26 03:00:00 2023 CEST
>> isdst=1 gmtoff=7200
>> Europe/Berlin Sun Oct 29 00:59:59 2023 UTC = Sun Oct 29 02:59:59 2023 CEST
>> isdst=1 gmtoff=7200
>> Europe/Berlin Sun Oct 29 01:00:00 2023 UTC = Sun Oct 29 02:00:00 2023 CET
>> isdst=0 gmtoff=3600
>>
>>
>> Test results are as follows:
>>
>> Northern Hemisphere side
>>
>> $ TZ=GMT faketime -m '2023-03-26 00:59:59' env TZ=MEZ-1MESZ,M3.5.0,M10.5.0/3
>> date
>> Sun Mar 26 01:59:59 MEZ 2023
>> $ TZ=GMT faketime -m '2023-03-26 00:59:59' env TZ=MEZ-1MESZ,M3.5.0,M10.5.0/3
>> java CheckDST1
>> Sun Mar 26 01:59:59 GMT+01:00 2023
>>
>> $ TZ=GMT faketime -m '2023-03-26 01:00:00' env TZ=MEZ-1MESZ,M3.5.0,M10.5.0/3
>> date
>> Sun Mar 26 03:00:00 MESZ 2023
>> $ TZ=GMT faketime -m '2023-03-26 01:00:00' env TZ=MEZ-1MESZ,M3.5.0,M10.5.0/3
>> java CheckDST1
>> Sun Mar 26 03:00:00 GMT+02:00 2023
>>
>> $ TZ=GMT faketime -m '2023-10-29 00:59:59' env TZ=MEZ-1MESZ,M3.5.0,M10.5.0/3
>> date
>> Sun Oct 29 02:59:59 MESZ 2023
>> $ TZ=GMT faketime -m '2023-10-29 00:59:59' env TZ=MEZ-1MESZ,M3.5.0,M10.5.0/3
>> java CheckDST1
>> Sun Oct 29 02:59:59 GMT+02:00 2023
>>
>> $ TZ=GMT faketime -m '2023-10-29 01:00:00' env TZ=MEZ-1MESZ,M3.5.0,M10.5.0/3
>> date
>> Sun Oct 29 02:00:00 MEZ 2023
>> $ TZ=GMT faketime -m '2023-10-29 01:00:00' env TZ=MEZ-1MESZ,M3.5.0,M10.5.0/3
>> java CheckDST1
>> Sun Oct 29 02:00:00 GMT+01:00 2023
>>
>>
>> Southern Hemisphere side
>>
>> $ TZ=GMT faketime -m '2023-03-26 00:59:59' env TZ=MEZ-1MESZ,M10.5.0,M3.5.0/3
>> date
>> Sun Mar 26 02:59:59 MESZ 2023
>> $bTZ=GMT faketime -m '2023-03-26 00:59:59' env TZ=MEZ-1MESZ,M10.5.0,M3.5.0/3
>> java CheckDST1
>> Sun Mar 26 02:59:59 GMT+02:00 2023
>>
>> $ TZ=GMT faketime -m '2023-03-26 01:00:00' env TZ=MEZ-1MESZ,M10.5.0,M3.5.0/3
>> date
>> Sun Mar 26 02:00:00 MEZ 2023
>> $ TZ=GMT faketime -m '2023-03-26 01:00:00' env TZ=MEZ-1MESZ,M10.5.0,M3.5.0/3
>> java CheckDST1
>> Sun Mar 26 02:00:00 GMT+01:00 2023
>>
>> $ TZ=GMT faketime -m '2023-10-29 00:59:59' env TZ=MEZ-1MESZ,M10.5.0,M3.5.0/3
>> date
>> Sun Oct 29 01:59:59 MEZ 2023
>> $ TZ=GMT faketime -m '2023-10-29 00:59:59' env TZ=MEZ-1MESZ,M10.5.0,M3.5.0/3
>> java CheckDST1
>> Sun Oct 29 01:59:59 GMT+01:00 2023
>>
>> $ TZ=GMT faketime -m '2023-10-29 01:00:00' env TZ=MEZ-1MESZ,M10.5.0,M3.5.0/3
>> date
>> Sun Oct 29 03:00:00 MESZ 2023
>> $ TZ=GMT faketime -m '2023-10-29 01:00:00' env TZ=MEZ-1MESZ,M10.5.0,M3.5.0/3
>> java CheckDST1
>> Sun Oct 29 03:00:00 GMT+02:00 2023
>
> Ichiroh Takiguchi has updated the pull request incrementally with one
> additional commit since the last revision:
>
> 8299194: CustomTzIDCheckDST.java may fail at future date
LGTM.
-------------
Marked as reviewed by naoto (Reviewer).
PR: https://git.openjdk.org/jdk/pull/11756
