java timezone data files

[Jilles Tjoelker]

Various Java ports want a "tzupdater" from Sun/Oracle which can be
annoying to download. I noticed that Ubuntu/Debian do not need this
tzupdater and have a package with timezone data files for Java. It turns
out that these files can be generated on FreeBSD as well.

A page about the Debian package is at
http://packages.debian.org/sid/tzdata-java
The interesting part is the .debian.tar.gz tarball in the "Download
Source Package" section, for example
http://ftp.de.debian.org/debian/pool/main/t/tzdata/tzdata_2011g-1.debian.tar.gz
This contains a patch debian/patches/java.diff with additional files
that Java needs and a file debian/rules which says how to build it.
The original source simply contains what we have in head
src/contrib/tzdata, plus three files solar87, solar88 and solar89.

I am using openjdk6 because Debian also uses it for this purpose.
Unfortunately, the port does not install javazic.jar but it is in the
work directory as build/bsd-i586/btjars/javazic.jar .

After copying our tzdata to a temporary directory and applying Debian's
java.diff to it, the following command creates the data files (in
tzgen-java/):

java -jar \
  /usr/ports/java/openjdk6/work/build/bsd-i586/btjars/javazic.jar \
  -V 2011g -d tzgen-java \
  africa antarctica asia australasia europe northamerica southamerica \
  etcetera factory backward systemv pacificnew \
  gmt jdk11_backward

This gives a few error messages but generates files.

These files are quite similar to those in /usr/local/jdk1.6.0/jre/lib/zi
and Europe/Amsterdam even matches exactly. Replacing the files, java
from jdk1.6.0 still appears to work correctly, although I do not know
how to test this more thoroughly.

-- 
Jilles Tjoelker