Can anybody help me on the code that will invoke a service from a java client and load the XML in a string.
You can invoke any flow service from java client by using invoke methods but I would rather create a web service and have the java client utilize the WSDL to invoke our service in which you can extract the xml from SOAP envelope and do whatever you want.
I would suggest a POX over HTTP POST as another approach to consider. Lot’s of info on the web about doing that in Java.