The document discusses using VM components in Mule to decompose a complex flow into smaller pieces to improve performance and control. It shows how to expose a CXF web service by breaking the flow into two parts connected by VM queues. This allows controlling each event queue separately and preventing overcommitting of resources. It demonstrates storing message properties before sending to the VM queue to retain them for the next flow, since properties may be lost passing through VM.

1. A Simple Web Service With VM

2. We all know how to expose a CXF based SOAP web services in Mule.
How about exposing the web service by decomposing a complex flow into smaller
part with VM component ??

3. One main reason to use this architecture, is that we can fragment the logic into
smaller pieces and can connect it and decouple each event, and is done mainly for
high performance and high control.

4. Advantage with breaking the flow with a queue :-
• Help to control on each event queue
• The service can be well-conditioned to load
• Preventing resources from being over committed when demand exceeds service
capacity.

5. So, let’s create our flow to expose a CXF web service by breaking the flow into 2 parts
connected with VM components as follows :-

6. You can see that we have used a set property after CXF component to store the
method name which is actually SOAP action here as the message properties generally
get lost if passed through a VM queue.

7. Our Mule config will be following :-
You can see in flow2 the SOAP action stored is provided as entry point for web service
implementing java class

8. Now, we can test our web service in SOAPUI and see that the web service is
generating a response which means it is working perfectly

9. So, if we are exposing a web service using VM endpoints the first thing we should keep
in mind is to store the outbound properties of the message before sending the
message to the VM outbound endpoint .
The main reason of doing is to protect the properties and get it in our next flow, since a
message may loose it’s outbound properties while passing through a VM.

10. In my next slide I will bring some other techniques of implementing VM endpoint in
our flow.
Hope you have enjoyed this simpler version.
Keep sharing your knowledge everywhere and let our mule community grow 
I have also shared this in my blog :- http://anirbansenchowdhary.com/blog/?p=220
So, Happy coding …