In our book we decided to focus mainly on two ESBs. Mule and ServiceMix. We chose these two since they represent two of the most popular opensource ESBs and also take two different approaches.
ServiceMix takes the JBI approach (such as openESB and petals) and nicely shows how to work with ServiceMix, but also shows in depth how JBI works.
The other ESB we cover intensily is Mule. Since they provide a lightweight approach to enterprise integration.
Although these two ESBs are the main focus of the book, we also mention other ESBs. We show how you can use Petals components and openESB components and also include an example with Spring Integration.
We wanted to make the book as practical as possible so we've stuffed it with examples showing all the different aspects you encounter when using ESBs. We provide a complete environment where you can run the examples for Mule and ServiceMix. The examples for instance show routing, transformation, connectivity, a seperate chapter on webservices, but also integration with BPEL and jBPM.