Why do you want to do it this way? Presumably the XML and the FF formats are different enough that after the branch you’ll have two distinct sets of steps to do the processing/transformation. You might consider putting the processing of each format into its own service.
You may want to consider a different approach. Generally speaking, a processing rule should be as specific as possible to avoid confusion and errant processing when new doc types/partners are added to the system.
Why do you want to make the processing decision in your service? Why not use the processing rule for what it was designed–to make the decision on which service to call based on sender, receiver and doc type. With what you’ve described so far, there doesn’t seem to be a compelling reason for a single service to handle both a FF and an XML document. You should have two different services, one for each. Those services may end up using other common services to do the work but at the top level they should probably be separate.
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