Why would I use Apache ServiceMix over just ActiveMQ

Question

I am starting to plan a new platform which needs to integrate various services from various externals platforms. Essentially I'm tying together a bunch of internal, homegrown services and several outside services we license from 3rd parties.

Generally speaking the external services are all web services but they are a mishmash of REST, SOAP and XML-RPC. Some of our internal services have REST API's but there are many things that aren't so easy: XMPP, Hessian, custom socket protocols, Java RPC, uWSGI, and the list goes on.

From my research it seems like an ESB like Apache ServiceMix might be a good fit for my needs. However it looks REALLY complex. I'm not launching rockets but I do need transactional messaging (mostly for eCommerce and entitlement stuff). I feel like the message queue ServiceMix uses under the hood (ActiveMQ) might be enough on its own.

Can anyone explain what ServiceMix provides above and beyond ActiveMQ? I know there is a lot but it is hard for an ESB n00b like me to really grasp the tangible difference when I'm waste-deep in buzzwords.

Thanks!

Answer 1

ServiceMix is an OSGi based container that allows you to deploy and run applications in a controlled runtime environment (like a J2EE container but less heavy weight and without programming to e.g. J2EE contracts). Thanks to OSGi you can partition your applications into parts and update/evolve these parts independently from each other. You can upgrade parts of your application without having to take down the entire application. There is far better life cycle management in OSGi then you get with standalone Java processes.

If you think of creating an application that will evolve over time, then OSGi is something you should consider. And ServiceMix provides you a runtime OSGi container to deploy your applications to. I highly recommend the book "OSGi in Action" from Manning.

For tying together different external services that might even use different transport protocols I recommend Apache Camel, which btw also deploys nicely into ServiceMix.

Btw, existing applications can be deployed into an OSGi container with fairly little effort (without requiring code changes).

Torsten Mielke FuseSource Web: www.fusesource.com Blog: http://tmielke.blogspot.com