| Best practices for dependency management [message #91676] |
Sat, 07 July 2007 02:11  |
Eclipse User |
|
|
|
Originally posted by: amottadelli_NO_SPAM.it.ibm.com
In Eclipse/OSGi plugin dependencies can be expressed in two different
ways: required plugins or import-package.
For our project (a rather large application), we are discussing the
relative merits of the two approaches.
Import-package looks superior as it allows for better maintainability,
but it appears that some Eclipse mechanisms depend on the Require-bundle
approach (buddy class loading, Extension points).
Can anybody provide any thoughts or pointers on the matter?
Many thanks,
A.Mottadelli
|
|
|
|
|
|
| Re: Best practices for dependency management [message #91857 is a reply to message #91707] |
Mon, 09 July 2007 17:17  |
| Eclipse User |
|
|
|
Hi,
> thanks. Yes, I know that using Import-package instead of Require-bundle
> is an OSGi best practice.
> My question is: is it also an Eclipse best practice?
That sounds like a very good question.
IMHO, looking at some higher-level bundles in Eclipse shows that
Import-package is highly overrated in some discussions.
(read "higher-level" as: "not belonging to the core framework").
Why do I think so?
How often would you like to say things like:
"I need a package org.eclipse.jdt.core.compiler, but I don't know,
which bundle should provide that package"? Or even: "The end-user
needs to be able to choose a providing bundle"?
(There is only one option: org.eclipse.jdt.core)
OTOH, you might want to see: "What other modules does a bundle depend on?"
If you are asked to choose between browsing a list of 80 packages or
12 bundles, which sounds more like giving you the big picture
(aka: the architecture of your application)?
BTW: what exactly is meant by "Has a lower fan out"? In my understanding,
a bundle that depends on 80 packages has a high fan in, compared to a bundle
depending on 12 bundles. But what is the fan out of a bundle?
(In my electronics classes I was taught that a high fan out is good, er?)
Why would one create components ("bundles") if these things cannot be used
to define the architecture?
Perhaps, Import-package comes from a level where "commodities" should
be integrated into an application. Everybody knows, how a HashMap works,
just give me any implementation, I don't care which. Fine.
Everyone knows how a Java-AST works? I don't care which one I will be
linked to? No!
Am I missing a point?
--
Stephan Herrmann
|
|
|
Powered by
FUDForum. Page generated in 0.02939 seconds
Home