[jboss-user] [JBoss jBPM] - Re: Native Java Code (POJO) Invocation

alex.guizar@jboss.com do-not-reply at jboss.com
Mon Aug 14 14:56:50 EDT 2006


Support for this feature is the goal of BPEL-135: pluggable invocation framework.

I have reviewed Apache WSIF more than once and have concluded that, while the interfaces are compatible with the current invocation model, the implementations are not. They assume the use of Java beans at the client side, while the BPEL engine mantains variables which all are basically DOM elements. Incorporating WSIF itself is a rather straightforward task. Rewriting the WSIF providers to deal with DOM elements is not.

Web services are moving from an RPC to a document-oriented approach. In the document world, endpoints either:
a) process the XML document directly, or
b) use the default XML-to-Object mapping with as few customizations as possible. Ideally, no customizations at all. You want to keep the gap between the document and the object model as narrow as possible.

Isn't the "overhead" of webservice calls mostly associated to XML-to-Java mapping? Considering a BPEL endpoint is document-oriented in that it mantains and manipulates variables of XML types exclusively, the *real* overhead is in calling plain Java code, since they are *not* oriented to documents. 

In order to do a good job of reducing overhead here, the BPEL engine would have to mantain variables of Java types. This is not a technical issue. The BPEL engine itself already mantains a number of Java objects in the jBPM variable space such as partner link and correlation set instances, among others. The real issues are:

Non-XML variables are out of the scope of the BPEL specification.
The jBPM project has a clear mindset of "one process language for each purpose", where purpose is one of workflow, orchestration, pageflow, etc. as opposed to "the ultimate all-purpose process language". The language you are looking for invoking your POJOs might be jPDL, not BPEL
I'd be really interested in knowing your thoughts here.

View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3965081#3965081

Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=3965081



More information about the jboss-user mailing list