As a standalone, JSR 173 defined its own entity resolver: javax.xml.stream.XMLResolver. Within Java SE however, it is beneficial to instead support the SAX Entity Resolver that is used by SAX and DOM. Doing so would unify the three XML parsers with regard to how external entities are resolved. The immediate benefit is that StAX can directly take advantage of the new Java SE Catalog API, that would in turn makes the Catalog
API available across all three parsers.