Thanks Stuart I am still a bit new to OSGI, I dont get much time to play around with it, so I hope the complexities of classloading in an OSGI environment does not overwhelm me, nevertheless the article seems quite well written, I will have a more in depth look into it
Thanks again Ivanhoe On Sun, Jan 3, 2010 at 6:17 PM, Stuart McCulloch <[email protected]> wrote: > 2010/1/4 Ivanhoe Abrahams <[email protected]> > > > Hi all > > > > I have been playing around with Drools 5.0.1 running as a service in > > Felix/Karaf. > > I finally got it working using a very simple HelloWorld drools example > (BTW > > this is also my first stab at using Drools, so I'm no expert on that > > framework). > > > > What I ended up with was. > > 1. A bundle that starts/initializes the Drools service and exposes a > method > > which allows clients to call the Rules engine service. > > 2. A domain Model bundle > > 3. A fragment bundle which imports the exported packages from the domain > > model bundle, as well as supplying the .drl file (which is the rules > > engines' rule base) > > 4. A client bundle which imports the exported packages from the model > > bundle. > > > > The client then creates a model object, and calls the Drools service > bundle > > to execute the simple test. > > The Service bundle is also the fragment-host for the fragment bundle. So > in > > that way it knows about the domain model, without explicitly declaring a > > dependency on it. > > > > So my question is. Does the above seem right? > > I have seen a couple of posts where the use of fragments are discouraged. > > But I am not sure how to cleanly achieve the above scenario without > > fragments. > > > > Also what bugs me about my solution above is that, since the Drools rules > > engine does some bytecode enhancement. I eventually had to add import > > package statements to the bundle which contains the domain model. This > just > > seems wrong because my Service bundle already imports packages from the > > underlying rules engine. > > > > FYI, this article discusses bytecode enhancement in OSGi > > http://www.infoq.com/articles/code-generation-with-osgi > > which might provide some hints or alternative solutions > > So basically the question is, are there better ways to achieve above > > modularization. > > How does one write a service, which needs to operate on some domain > model, > > but without knowing what those domain models will be beforehand. > > > > Thankyou in advance > > Ivanhoe > > > > -- > Cheers, Stuart >
