Simulate SAP sending IDoc for testing

I need to test some mapping sevices for mapping an IDoc to a record, but I don’t want to involve SAP. I have an IDoc formatted as a text file, which I could load, but I am having difficulty getting the IDoc loaded and put into a record. I think I could use TransformFlatToHierarchy if I could get the IDoc.txt loaded. Any suggestions , with out having to convert the IDoc to XML.