Thanks for the wise advice...

Except that I have the distinct feeling that the OSGi environment is
not fully understood, I think the outline of "3 parts" might be what
we need.
But before that, IF you are modeling "execution environment" (as it is
called in OSGi) explicitly, which is fine although not particularly
common, this is no different from modeling this explicitly for Java SE
either, since JDK 1.5, 1.6 and 1.7 are exactly that (by the EE
definition in OSGi at least). I don't know if you can fool a JDK1.6
compiler to use JDK1.5 library + generate 5.0 byte codes (I would like
that, since there are bugs in the 1.5 generics compiler) but the
general approach would be the same as for CLDC, CDC, Android and GWT
EEs as well. Worth thinking about, now when you have mentioned it, but
it is NOT an OSGi-specific concern, even though it would cover OSGi
case as well, since the bundle is allowed to declare "Minimum
Execution Environment" and the container will not start the bundle if
it can't provide it. And just to be clear; The EE of a container is
almost always predefined and not user manipulated, common ones being
equivalent to CDC and JRE1.x. Users who tries to 'extend' these are
quickly out in deep waters...

The concept that the 'container' exposes something to the bundle does
not exist in default OSGi (bootstrap classloader exposure is an
exception rather than the rule). IF my bundle needs org.w3c.xml
package, my bundle is required to Import-Package:org.w3c.xml. It is
not available, just because it is part of the JRE I am running. Only
the java.* packages are. This is important to understand.
And the "requirements" declared by the bundle is called the
Manifest.MF, and can be shared with the Java SE Jar in most cases.
There is an internal classpath within the bundle, a.k.a
Bundle-ClassPath which is normally '.', i.e. the root of the Jar. But
the discussion around WAB (Web Application Bundle) is that this
feature allows WABs to be compatible with WARs, i.e. deployable in
either environments.

Both these 'overlaps' should in my opinion be leveraged.


Cheers
-- 
Niclas Hedhman, Software Developer
http://www.qi4j.org - New Energy for Java

I live here; http://tinyurl.com/3xugrbk
I work here; http://tinyurl.com/24svnvk
I relax here; http://tinyurl.com/2cgsug

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