class NetUtils {

    public static boolean isIp6InNetwork(final String ip6, final String ip6Cidr) {
        IPv6Network network = null;
        try {
            network = IPv6Network.fromString(ip6Cidr);
        } catch (final IllegalArgumentException ex) {
            return false;
        }
        final IPv6Address ip = IPv6Address.fromString(ip6);
        return network.contains(ip);
    }

}