[blfs-dev] Mercurial or wget for openjdk?

[Pierre Labastie]

Hi all,

Sorry for discussing this again, but before the timing given below, I was
wondering what the best approach for downloading OpenJDK files was. Using
mercurial, it amounts to:
----------
hg clone http://hg.openjdk.java.net/jdk8u/jdk8u<rev>
cd jdk8u<rev>
sh get_source.sh
sh common/bin/hgforest.sh update -r jdk8u<rev>-b<build> # not really needed
----------
Note that mercurial is needed (obviously), but mercurial depends only on
Python, which is a very basic package, and builds very fast (a few tenths of
SBU). hgforest is optimized to retrieve several repositories at the same time,
so the download time is not too long. Actually, timing gives:
-------------
time (
hg clone http://hg.openjdk.java.net/jdk8u/jdk8u60
cd jdk8u60
sh get_source.sh
sh common/bin/hgforest.sh update -r jdk8u60-b27 )
...
real    6m31.868s
user    0m0.896s
sys     0m0.060s

The other approach is to use wget to download tarballs, as proposed by
Fernando. For measuring download+unpack time, I use a version slightly
different from
http://lists.linuxfromscratch.org/pipermail/blfs-dev/2015-May/030258.html:
time (
PACKAGE=jdk8u60-b27.tar.bz2
URL=http://hg.openjdk.java.net/jdk8u/jdk8u60
URL_END=archive/$PACKAGE
wget $URL/$URL_END
tar xf $PACKAGE
for additional in corba hotspot jaxp jaxws langtools jdk nashorn; do
  wget $URL/$additional/$URL_END -O $additional.tar.bz2
  mkdir -p jdk8u60-jdk8u60-b27/$additional
  tar --stripcomponents=1 \
      -C jdk8u60-jdk8u60-b27/$additional \
      -x -f $additional.tar.bz2
done
)
...
real    2m56.273s
user    0m8.716s
sys     0m2.472s

So definitely, the wget approach is shorter. OTOH the mercurial approach is
much simpler and less prone to errors. If using wget, I think I'll use some
approach similar to what we do for X, as suggested by Fernando, but it would
be still complicated, unless maybe we make a file with 4 fields per line:
tarball-name, md5 extracted-dirname, final-dirname.

Thoughts?

Pierre