Appendix A. ServiceMix 4.0
The examples in this book are based on ServiceMix version 3.2.1, which is the latest production release at the time of writing. But a milestone of the next version of ServiceMix is already available: version 4.0. This version of ServiceMix is based on a new architecture and therefore has many changes compared to version 3.x. We chose to use ServiceMix 3.2.1 in this book because ServiceMix 4 wasn’t yet available. With ServiceMix 4.0, it will only become easier for integration developers to use ServiceMix in your integration projects.
Let’s look at the new architecture of ServiceMix 4.0 in the first section. After that, we show you an example of how you can use ServiceMix 4.
The new ServiceMix architecture tries to simplify the classloading mechanism, the development of (JBI) components, and packaging of your developed integration logic. The foundation of ServiceMix 4 is an OSGi container, which takes care of classloading and deployment of new or changed components. OSGi also provides a packaging structure that ServiceMix can use.
Before we dive into the details of OSGi in the next section, let’s look at the revised architecture, shown in figure A.1, as described on the ServiceMix 4 website (http://servicemix.apache.org).
Figure A.1. The new architecture of ServiceMix 4. The architecture is described from three viewpoints: the developer view, the technology view, and the kernel view.
