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Ultimately, the Scala API for Daffodil converts the JDOM objects into Scala's native XML objects, e.g., scala.xml.Elem being the class of Element nodes.
The Java API returns the JDOM objects directly to the caller.
Namespaces and Prefixes
The Daffodil implementation uses uses attributes in a few distinct namespaces to embellish JDOM Elements.
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which uses the XML numeric character entity to directly insert the remapped #xE000 character directly. The use of DFDL character entities simply allows the notational convenience of the use of the symbolic form of these entities (NUL, CR, LF, HT, VT, FF, etc.), or the DFDL numeric entities form (for example "%#x02;") for notational consistency across DFDL schema and TDML test files.
Use of the DFDL character entities is preferred as it is portable to other DFDL implementations than just Daffodil. The remapping of XML-illegal characters to the PUA is a Daffodil-specific behaviour.