this.client = client == null ? "UNKNOWN" : client; this.version = version == null ? "UNKNOWN" : version;
this.client = client == null ? UNKNOWN : client; this.version = version == null ? UNKNOWN : version;
    public ClientVersion(String client, String version) {        this.client = client == null ? "UNKNOWN" : client;        this.version = version == null ? "UNKNOWN" : version;    }