I have a side project which allows Schemagen to be run as a maven target, (i.e. directly from the POM, without using ant-call):
https://github.com/ephemerian/schemagen-maven I'm proposing to migrate that project to Apache Jena, by adding it as a maven module that will be generated and published as part of a main Jena release. The chief advantages of this are (i) any committer can update the code, and (ii) it will be available as a maven artefact without requiring users to install locally or publish it in their own repos. This is a call for comments, questions or objections. Ian