Seeking Java install clarifications and insight

[Cameron Simpson]

On 24Mar2007 22:56, Aubrey Barnard <aubreys_key at yahoo.com> wrote:
| I am looking for someone to help me with this GCJ vs. Sun's Java thing, or
| point me to a good explanation. [...]
| What I know:
| I get the difference about free vs. proprietary and know that with Sun
| GPL-ing Java last year (and libraries this year) that Fedora 8 may
| incorporate Sun's Java.
| 
| What I want to know:
| Why is the installation of Sun's Java so complicated?

It's not. Untar/unzip the package into a directory (eg
/opt/j2sdk-sun-1.5.0nb4.0).  Make sure the bin directory (eg
/opt/j2sdk-sun-1.5.0nb4.0/bin for the example) is in $PATH, ahead
of other Javas you do not want to use.  Possibly point $JAVA_HOME at
/opt/j2sdk-sun-1.5.0nb4.0 as well.

If you want it in a mozilla/firefox browser, go to the plugins subdir
and symlink the .so. Eg:

  $ cd /opt/firefox-2.0.0.3-enGB/plugins
  $ ls -l libjavaplugin_oji.so
  lrwxrwxrwx  1 root root    66 Mar 22 15:07 libjavaplugin_oji.so -> /opt/j2sdk-sun-1.5.0nb4.0/jre/plugin/i386/ns7/libjavaplugin_oji.so

Personally, I often keep a /opt/j2sdk symlink around, pointing at my preferred
release. Then a lot of those symlinks become stable and not version specific,
thus not needing updating for new installs.

| Why doesn't the normal path of install with yum and run work?

Because it's not available as an RPM, AFAIK. Besides, yum and rpm generally
only let you have one variety lying around. I just drop binary installs in
/opt, as described above. That way you can test against stuff.

| What is with all the "compat" stuff?
| How safe is it for GCJ and Sun's Java to coexist?

Shrug. Install them in different places and everything's fine. You only
ever run a program in one or another at a time anyway.

| How does JPackage provide me Sun's Java?
| When Sun releases the source for their libraries under the GPL, how does
| this affect GCJ?

It might let you use Sun's libs with a GCJ compile/execute front end.
It may let people produce and distribute RPMs for the Sun stuff more
freely. And stuff like that.

| What is the best set of install instructions to use based on
| compatibility, stability, ease of use, ease of (un)installation?

My way, uninstall is a single "rm -r /opt/j2sdk-sun-1.5.0nb4.0"
command.

My 2 cents' worth,
-- 
Cameron Simpson <cs at zip.com.au> DoD#743
http://www.cskk.ezoshosting.com/cs/

CP/M is to metric as cockroaches are to a Timex watch
        - booter at catnip.berkeley.ca.us