The trimmed version of Jing included in XXE (
relaxng.jar) is used
to load and validate RELAX NG schemas associated to XML documents (XML and compact syntaxes are both supported);
to fully validate XML documents conforming to RELAX NG schemas, each time these documents are opened and saved, and each time a full validation is explicitly requested by the user (command→ ).
Jing is not used to implement guided editing. That is, Jing is not used to determine the content model of the element being edited. A quick, incremental, version of the algorithm that computes the derivative of a pattern is used for that.
The implementation of W3C XML Schema Datatypes used in RELAX NG schemas (e.g.
xsd:int) is the work of XMLmind. This implementation is very different from the implementation of W3C XML Schema Datatypes included in the original Jing. This implementation is shared by the version of Jing included in XXE and by our own W3C XML Schema validator.
XXE supports attribute default values as specified in RELAX NG DTD Compatibility. The compatibility of the schema with this feature is (very strictly) checked by XXE and not by Jing. This means that a schema found valid by Jing but improperly using this feature will be rejected by XXE.