JavaOne 2015 saw a series of talks by the Project Jigsaw team about modularity in Java 9. This one details different migration scenarios.

nipafx (Nicolai Parlog)

A summary of the JavaOne 2015 talk on advanced modular development in Java 9 by the Project Jigsaw team. Covers two migration strategies: top-down migration (converting application JARs to modules using module-info.java, with unmodularized dependencies placed on the module path as automatic modules) and bottom-up migration (converting libraries to modules while allowing unconverted applications to continue using the class path). Key tools discussed include jdeps for dependency analysis, -genmoduleinfo for generating module-info drafts, -addmods for specifying root modules, and jlink for creating minimal runtime images. Also addresses Q&A topics including module encapsulation with reflection, OSGi compatibility, JNI support, and Maven integration plans.

JavaOne 2015: Advanced Modular Development