Freelance server, Model Two in Java

import org.zeromq.ZContext;
import org.zeromq.ZFrame;
import org.zeromq.ZMQ;
import org.zeromq.ZMQ.Socket;
import org.zeromq.ZMsg;

// Freelance server - Model 2
// Does some work, replies OK, with message sequencing

public class flserver2
{
public static void main(String[] args)
{
if (args.length < 1) {
System.out.printf("I: syntax: flserver2 <endpoint>\n");
System.exit(0);
}
ZContext ctx = new ZContext();
Socket server = ctx.createSocket(ZMQ.REP);
server.bind(args[0]);

System.out.printf ("I: echo service is ready at %s\n", args[0]);
while (true) {
ZMsg request = ZMsg.recvMsg(server);
if (request == null)
break; // Interrupted

// Fail nastily if run against wrong client
assert (request.size() == 2);

ZFrame identity = request.pop();
request.destroy();

ZMsg reply = new ZMsg();
reply.add(identity);
reply.add("OK");
reply.send(server);
}
if (Thread.currentThread().isInterrupted())
System.out.printf ("W: interrupted\n");

ctx.destroy();
}
}