A SEF grammar is created to be used with the Java CC program to autogenerate a SEF parser. The SEF parser can be run with specially written X12 code on any SEF file to automatically create an EDI object model for that SEF file. A programmer can then write application code to use the EDI object model to parse an EDI document that the SEF file describes and generate in memory an EDI object model instance for that EDI document. The application code is also used to employ the EDI object model instance to efficiently process the EDI document's EDI transaction. In addition, the application code is used to employ the EDI object model on the EDI object model instance to emit an EDI document for further use.