mspoller.java

package guide;

import org.zeromq.SocketType;
import org.zeromq.ZMQ;
import org.zeromq.ZContext;

//
//  Reading from multiple sockets in Java
//  This version uses ZMQ.Poller
//
public class mspoller
{

    public static void main(String[] args)
    {
        try (ZContext context = new ZContext()) {
            // Connect to task ventilator
            ZMQ.Socket receiver = context.createSocket(SocketType.PULL);
            receiver.connect("tcp://localhost:5557");

            //  Connect to weather server
            ZMQ.Socket subscriber = context.createSocket(SocketType.SUB);
            subscriber.connect("tcp://localhost:5556");
            subscriber.subscribe("10001 ".getBytes(ZMQ.CHARSET));

            //  Initialize poll set
            ZMQ.Poller items = context.createPoller(2);
            items.register(receiver, ZMQ.Poller.POLLIN);
            items.register(subscriber, ZMQ.Poller.POLLIN);

            //  Process messages from both sockets
            while (!Thread.currentThread().isInterrupted()) {
                byte[] message;
                items.poll();
                if (items.pollin(0)) {
                    message = receiver.recv(0);
                    System.out.println("Process task");
                }
                if (items.pollin(1)) {
                    message = subscriber.recv(0);
                    System.out.println("Process weather update");
                }
            }
        }
    }
}