@Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;
            Version version1 = (Version) o;
            return version == version1.version;
        }
IP version.  Can be compared with ==, !=, and equals().
node-repository/src/main/java/com/yahoo/vespa/hosted/provision/node/IP.java