Following the Checkstyle lead, Checkstyle Addons has also moved to Java 8 (hence the new major version).
propertyFile option of the PropertyCatalog check
features a new placeholder.
Starting with Checkstyle 7.0, Checkstyle requires Java 8. So, Checkstyle Addons is now also compiled
for Java 8 by default. If you are on a previous Java version, that’s fine! You may use the artifacts
java6, respectively. They are functionally equivalent, but work with previous
levels of Java and the corresponding older versions of Checkstyle.