Re: [tycho-user] framework extension bundle and rt.jar versus tools.jar

[Andreas Sewe <andreas.sewe@xxxxxxxxxxxxxx>]

Hi Justin,

> I've been told by multiple people in the Eclipse and Tycho community that the extension bundle is the Correct way to expose these packages, with these two blog posts being referred to
> 
> http://blog.springsource.org/2009/01/19/exposing-the-boot-classpath-in-osgi/
> 
> http://blog.meschberger.ch/2008/10/osgi-framework-extension-as-maven.html

thank you for the pointers. Very interesting.

There is a one crucial difference, though. The framework extension
mechanism can only be used to expose things which are on the JVM's boot
classpath (like sun.misc.Unsafe) but which are not considered to be part
of the execution environment (like java.*).

The tools.jar, however, resides rarely (never?) on the JVM's boot
classpath. So, as far as I can tell, the framework extension mechanism
doesn't apply to it. Hope that explains the difference.

So, for rt.jar, frameworke extensions fit the bill nicely, but for
tools.jar you need another workaround.

> I believe there are licensing restrictions for modifying tools.jar and rt.jar, so the framework extension bundle avoids that complication.

Yes, I am aware of these restrictions. In fact, the solution presented
in [1] does *not* require repackaging of the tools.jar.

Best wishes,

Andreas

[1] <http://www.codetrails.com/blog/osgi-ify-your-tools-jar>

-- 
Codetrails UG (haftungsbeschränkt)
The knowledge transfer company

Robert-Bosch-Str. 7, 64293 Darmstadt
Mobile: +49-170-811-3791
http://www.codetrails.com/

Managing Director: Dr. Marcel Bruch
Handelsregister: Darmstadt HRB 91940