}

    Violation maybeViolation(final JApiCompatibility member) {
        if (!(member instanceof JApiClass)) {
            return null
        }

        if (!changed(member)) {
            return null
        }

        Optional<CtClass> oldClass = member.oldClass
        Optional<CtClass> newClass = member.newClass
        if (!oldClass.isPresent() || !newClass.isPresent()) {