help me implementing Web Service input/out activity like Windows Workflow Foudation

I’m new to JOpera, right now I’m finding difficulty in finding information about adding BPELAdapter. Could you please someone help me finding
•BPEL snippet which I can use in JOpera.
•State persistent in JOpera
For example :
I would like to create a sample workflow for procurement, say I would like to have 3 web service methods.
And deploy that as state persistent web service, first I would like to call GeneratePurchaseOrder web method and that returns me XYZ string. From different machine I would like to invoke the same Workflow instance and call GenerateInvoice etc..
Above workflow if I use Windows Workflow Foundation there is something called Web Service Input /Out Activity which will wait for the web service call to me made so in that way it’s easy for me implement. Is there anything similar in JOpera? to achieve the above functionality.

Jayakumar A