The C++ implementation is composed of the source files listed below. As is the case with the Java implementation, there's no new ground and not a lot to elaborate.
FlatToXML.cpp: the main routine for the C++ application with flat files as source
FlatSourceConverter.cpp: the class that drives conversion from flat files to XML
FlatSourceConverter.h: the header file for the FlatSourceConverter class
FlatRecordReader.cpp: the class that handles reading flat file records and converting to XML
FlatRecordReader.h: the header file for the FlatRecordReader class
XMLToFlat.cpp: the main routine for the C++ application with flat files as target
FlatTargetConverter.cpp: the class that drives conversion from XML to flat files
FlatTargetConverter.h: the header file for the FlatTargetConverter class
FlatRecordWriter.cpp: the class that handles reading XML and building and writing flat file records
FlatRecordWriter.h: the header file for the FlatRecordWriter class
DataCellN.cpp: the class that handles legacy format number fields with implied decimal places
DataCellDateYYYYMMDD.cpp: the class that handles date fields in YYYYMMDD representation in legacy formats
DataCellDateYYYYMMDD.h: the header file for the DataCellDateYYYYMMDD class