Calls to static interface methods compile on Java 8 but not on Java 9 because of a new bytecode restrictrion.
public interface JDK8InterfaceMethods {
// cannot call either of these from Clojure
public static long staticMethod0(long v) { return v; }
public static String staticMethod1(String s) { return s; }
}
https://dev.clojure.org/jira/browse/CLJ-2284
Interface default methods are unaffected.