How to call JSP that outputs XML without HTTP request

Question

It should be a simple solution but I can't seem to find a concise recommendation anywhere. We are building a B2B subsytem for our app and we need to send XML to our vendor. I'm evaluating the possibility of using JSPs for that and everything looks good until the time you actually want to invoke it. It's obvious how to code the JSP itself, but I'm looking for an efficient way to call it to generate XML. We do not have an HTTP request or a servlet, the communication is on the EJB level. So I can't get a RequestDispatcher for example, and we don�t have HttpServletRequest/HttpServletResponse either. It is NOT a servlet or JSP calling another JSP, it's a regular Java class or EJB.
Ideally, I would rather bypass the whole HTTP infrastructure and just use JSP as a formatter. So it boils to a question of how to invoke it and how to pass the parameters without HTTP session or request. One of the alternatives we are reviewing is using XSP but we would prefer JSPs if we can figure out how to call it efficiently. HttpUrlConnection is not a good option, we'd like a direct call.
Any suggestions will be greatly appreciated.

Answer 1

Thanks for the response. Let me clarify the requirements for the question. The way we are supposed to send XML to the vendor is via CORBA (don't ask me why:-) where the only parameter essentially is a string containing the XML document. So the quesiton is not how to send it to the vendor, but how to format our JavaBeans into XML.
We can't use JAXB because it doesn't support schema. We tried a few libraries out there but they stumble on our schema and we can't change it because it comes from the vendor. So it sounds like our only choice for today is to generate XML ourselves.
The data is stored in JavaBean packet objects and that's our input. Our output should be a string with XML document conforming to the schema. Posting a request to ourselves will of course work, but that's too much unnecessary overhead. Another option is implementing HttpServletRequest and HttpServletResponse and calling service method directly. Better suggestions?