http://mail.openjdk.java.net/pipermail/core-libs-dev/2017-August/048756.html

This seems to be an issue when determining if a class is an isolated nested class when the enclosing class is another nested class. It checks if it's a top level class.

The thread reports the following problems and please create separate issues if appropriate:
(1) isolated nested classes trying to create a multi-release jar
(2) creation of a corrupt jar on SPARC64