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From: Caspar MacRae <earcam@gmail.com>
Date: Thu, 15 Apr 2010 18:40:13 +0100
Message-ID: <v2ne5058b6a1004151040v26dcdf73g4ff8635c806bcb90@mail.gmail.com>
Subject: Re: Custom Class Loader for Hadoop M/R jobs?
To: general@hadoop.apache.org
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ServiceMix and ActiveMQ are also using OSGi in their core AFAIK.

The way this (these) problems have been solved is more of an afterthought,
and regardless is quite simplistic (thinking of classloader isolation in web
containers, app servers, and the monolithic WARs produced as a result),
however OSGi's approach to modularity provides a truly elegant solution.

wrt to the ticket https://issues.apache.org/jira/browse/MAPREDUCE-243, Dave
Savage is a nice chap who works for Paremus (an enterprise OSGi provider) I
spoke with him at the recent OSGi devcon in London and he did quite a bit of
work to get this working for private clients - I'm sure with his expertise
it would not be a huge effort to get this rolling again.


On 15 April 2010 18:23, Segel, Mike <msegel@navteq.com> wrote:

> Ok, so are you using OSGi's code, or just writing your own code to
> implement a published API/specification?
>
> I realize this is getting off topic, so you may just want to e-mail me
> directly.
>
> Thx
>
> -Mike
>
> -----Original Message-----
> From: Marcel May [mailto:marcel.may@consol.de]
> Sent: Thursday, April 15, 2010 11:35 AM
> To: general@hadoop.apache.org
> Subject: Re: Custom Class Loader for Hadoop M/R jobs?
>
>
> On Apr 15, 2010, at 6:27 PM, Segel, Mike wrote:
>
> > Caspar,
> >
> > While IANAL, I did a first blush read of OSGi's Specification License,
> Version 1.0. on the website link:
> http://www.osgi.org/Specifications/Licensing as well as the license on the
> download page: http://www.osgi.org/Download/Release4V42?info=nothanks.
> >
> > In a nutshell, OSGi's Specification License, Version 1.0. is incompatible
> with Apache's.
> >
> > That alone can explain why Apache projects won't touch OSGi.
> >
>
> http://felix.apache.org/
>
> > From a more practical issue, this problem is solved in other Apache
> projects, so why not borrow from another Apache project like Tomcat?
> >
> > Does that make sense? It appears OSGi is a non-starter.
> >
> > HTH
> >
> > -Mike
> ...
>
> Cheers,
> Marcel
>
>
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