log.error(ex);
System.err.println(ex);
    public static void main(String[] args) {        String props;        ProtocolTester t;        Harness h;        if(args.length < 1 || args.length > 2) {            System.out.println("ProtocolTester <protocol stack spec> [-trace]");            return;        }        props=args[0];        try {            h=new Harness();            t=new ProtocolTester(props, h);            System.out.println("protocol specification is " + t.getProtocolSpec());            h.down(new Event(Event.BECOME_SERVER));            for(int i=0; i < 5; i++) {                System.out.println("Sending msg #" + i);                h.down(new Event(Event.MSG, new Message(null, null, "Hello world #" + i)));            }            Util.sleep(500);            t.stop();        }        catch(Exception ex) {            log.error(ex);        }    }