Before you can convert between data packets and XML documents, you must define the relationship between the metadata in a data packet and the nodes of the corresponding XML document. A description of this relationship is stored in a special XML document called a transformation. 

Each transformation file contains two things: the mapping between the nodes in an XML schema and the fields in a data packet, and a skeletal XML document that represents the structure for the results of the transformation. A transformation is a one-way mapping: from an XML schema or document to a data packet or from the metadata in a data packet to an XML schema. Often, you create transformation files in pairs: one that maps from XML to data packet, and one that maps from data packet to XML. 

In order to create the transformation files for a mapping, use the XMLMapper utility that ships in the bin directory.