Large Enterprise Java Application - Modularization

Question

I work for a country-wide company, so the software we develop is large scale.

Our core system is Web based including webservices. We are currently redesigni

Answer 1

I'd highly recommend reading Kirk Knoernschild's "Java Application Architecture: Modularity Patterns with Examples Using OSGi". You could start by modularizing the app before migrating to OSGi (and I'd definitely invest in good test coverage if you don't already have it).

If you're using servlet spec 3.0 then look at using web-fragments.

In terms of the structure you've shown, I'd say don't nest anything (except web-fragments), the WARs can become WABs (web application bundle - basically a skinny WAR). Also leverage OSGi's μServices as much as possible - that's where the fun starts =)

Enterprise OSGi frameworks like Karaf and Virgo offer a lot of support while you're straddling the JEE-OSGi divide (Equinox and Felix alone are a little to barebones).