Error updating tzdata 2018f (Released 2018-10-18) with tzupdater-2.2.0

Question

I\'m trying to update JVM\'s Time Zone info using TZUpdater 2.2.0.

> [root@local tzupdater-2.2.0]# java -jar tzupdater.jar -V
  tzupdater version 2.2.0-b0         


        

Answer 1

Yes, the rules for Japan in 1948-1951 changed in 2018f in an "interesting" way: officially, Japan's fall back occurred at 25:00 on Saturday, instead of 01:00 on the Sunday. That confused the Java time zone updater, as well as my own Noda Time project.

There's now a commit to avoid 25:00 in the "rearguard" format - the rearguard format is basically more conservative, avoiding things like Ireland's negative DST.

I would expect a 2018g release at some point reasonably soon, to include that fix. Assuming the tzupdater tool uses the rearguard appropriately, I'd expect that to sort things out. If you can possibly wait until then, I'd do so. Otherwise, use the -l flag on tzupdater to specify a different data source, e.g. for 2018e: https://data.iana.org/time-zones/releases/tzdata2018e.tar.gz