public String typeString() {
        switch (options.type) {
        case ZMQ.ZMQ_PAIR:
            return "PAIR";
        case ZMQ.ZMQ_PUB:
            return "PUB";
        case ZMQ.ZMQ_SUB:
            return "SUB";
        case ZMQ.ZMQ_REQ:
            return "REQ";
        case ZMQ.ZMQ_REP:
            return "REP";
        case ZMQ.ZMQ_DEALER:
            return "DEALER";
        case ZMQ.ZMQ_ROUTER:
            return "ROUTER";
        case ZMQ.ZMQ_PULL:
            return "PULL";
        case ZMQ.ZMQ_PUSH:
            return "PUSH";
        default:
            return "UNKOWN";
        }
    }