The issue with OSGi not supporting Java 9 has finally seen some movement. See the update at https://github.com/bndtools/bnd/issues/2227#issuecomment-370600204 <https://github.com/bndtools/bnd/issues/2227#issuecomment-370600204>. It seems support for multi-release jars has finally been added to the OSGi spec. A good explanation can be found in the OSGi blog at http://blog.osgi.org/2018/02/osgi-r7-highlights-java-9-support.html <http://blog.osgi.org/2018/02/osgi-r7-highlights-java-9-support.html>.
It remains to be seen how long it will take the various OSGi implementations to add this support. Ralph