Talk:Equinox
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Alex Blewitt said ...
Thanks for speaking up Alex. The title of my post was intentionally more radical than the content. All I wanted to point out is that Equinox (in contrast to Felix) is a meta framework. To turn it into actual OSGi framework you can apply various tweaking functions to it and thus obtain various OSGi frameworks. Obviously one of such tweaking functions can be identity (e.g. no change) yielding OSGi framework known as Equinox. But the meta capacity is something interesting and I wanted to point it out.
--JaroslavTulach 11:12, 12 October 2009 (UTC)
Actually, most of this post is a fabrication. Equinox is an OSGi framework, as evidenced by the fact that it passes the OSGi TCK, without which it couldn't be called an OSGi framework. So the assertion that 'Equinox is not an OSGi framework' is incorrect.
It does highlight something that people often get confused by; OSGi is not meant to be an exclusive specification of 'you can only use this'. It's supposed to be *modular*. And as such, you can add modules to bring your own functionality on top of any system; you're not 'limited' in some arbitrary way to only use those modules as specified in the OSGi spec.
Equinox, by itself, is a standalone OSGi engine. The framework differs from Felix's implementation in that the console is bundled in the 'org.eclipse.OSGi' framework bundle; whereas in Felix it's a separate engine.
But services like the extension registry are provided in their own bundle as a separate OSGi bundle. Just because the extension registry isn't defined in the OSGi core spec doesn't mean it's not OSGi - it's just another layer on top, much like the reference impl for remote services is handled by using different underlying bundles (e.g. ECF or SOAP).
Lastly, OSGi isn't a 'constraining' system which means that you are locked into precisely one way of working. In fact, until 4.2, there wasn't even a standard set of properties to bring up a framework; they were all non-standard properties in that way. At least that's starting to normalise.
--Alex Blewitt 12:11, 11 October 2009 (CEST)