[gentoo-java] Re: Maven from source - version 2.x or 3.x ?

["Jörg Schaible" <joerg.schaible@gmx.de>]

Hi Robert,

Robert Burrell Donkin wrote:

> On Tue, May 24, 2011 at 12:52 PM, Kasun Gajasinghe
> <kasunbg@gmail.com> wrote:
>> On 24 May 2011, at 14:37, Petteri Räty
>> <betelgeuse@gentoo.org> wrote:
>>> On 05/23/2011 07:52 PM, Kasun Gajasinghe wrote:
>>>
>>>>>
>>>>> maven-bin 2.x support continues to work through the binary package?
>>>>
>>>> Yes, we can keep supporting maven-bin 2.x for maven users. Though the
>>>> packagers of projects based on maven won't be able to use the support
>>>> for maven 2.x if we start with 3.x.This project's focus is more
>>>> towards packagers, right?  I think Serkan or people who are more
>>>> familiar with this can give an exact answer.
>>>>
>>>
>>> So are you discussing which version of Maven to build from source or
>>> which version to target ebuild infrastructure for? Those two don't
>>> necessarily need to be the same and your topic implied the former but
>>> the above talks about the latter.
>>
>> Well, mainly this project is inclined towards packagers.
>> But of course the users are targeted too. Currently, users have the
>> maven-bin too
>> which means they have a choice in hand. The problem with Maven 3 is
>> that some important plugins for users are not
>> supported yet.
> 
> AIUI the situation is more complex than that
> 
> maven seems to be moving towards requiring specific core versions for
> builds. some  projects i develop require maven 2, some maven 3. i
> manage this situation with a set of custom scripts and installations
> independent of gentoo. i expect other developers now work in a similar
> way. (same goes for jdks.) the gentoo java stuff just gets in my way
> now for development.

Why? I have emerged maven:1.0, maven:1.1, maven:2.0, maven:2.2 and 
maven:3.0. I've selected my default version with eselect. However, I can use 
any of those versions at the same time:

/usr/bin $ ls -lGgo m*v*n*
lrwxrwxrwx 1    34 Jan 22 14:07 maven-1.0 -> /usr/share/maven-
bin-1.0/bin/maven
lrwxrwxrwx 1    34 Jan 22 14:07 maven-1.1 -> /usr/share/maven-
bin-1.1/bin/maven
lrwxrwxrwx 1     7 Jul 19  2010 mvn -> mvn-3.0
lrwxrwxrwx 1    32 Apr 30  2010 mvn-2.0 -> /usr/share/maven-bin-2.0/bin/mvn
lrwxrwxrwx 1    32 Apr 30  2010 mvn-2.2 -> /usr/share/maven-bin-2.2/bin/mvn
lrwxrwxrwx 1    32 Mar 10 18:17 mvn-3.0 -> /usr/share/maven-bin-3.0/bin/mvn

All that eselect effectively does is to switch the unversioned link. You may 
call any of those scripts (well, you should not have set MAVEN_HOME at all, 
the Maven start script will do this for you anyway).

> FWIW one unresolved challenge for linux distributions with the rise of
> bytecode languages (such as Java) is that compressed bytecodes are not
> binaries in the usual sense (platform dependent machine executable
> machine code). i know that it's a hard thing for the linux community
> to hear but it's about time that the community acknowledged that these
> languages are now mainstream and stop trying to force them into a
> inappropriate provisioning model.

To build Maven from source in Gentoo I wonder about the hen-and-egg problem.

Cheers,
Jörg