clonecli2.java

package guide;

import java.util.HashMap;
import java.util.Map;

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

/**
 * Clone client Model Two
 * 
 * @author Danish Shrestha <dshrestha06@gmail.com>
 * 
 */
public class clonecli2
{
    private static final Map<String, kvsimple> kvMap = new HashMap<>();

    public void run()
    {
        try (ZContext ctx = new ZContext()) {
            Socket snapshot = ctx.createSocket(SocketType.DEALER);
            snapshot.connect("tcp://localhost:5556");

            Socket subscriber = ctx.createSocket(SocketType.SUB);
            subscriber.connect("tcp://localhost:5557");
            subscriber.subscribe(ZMQ.SUBSCRIPTION_ALL);

            // get state snapshot
            snapshot.send("ICANHAZ?".getBytes(ZMQ.CHARSET), 0);
            long sequence = 0;
            while (true) {
                kvsimple kvMsg = kvsimple.recv(snapshot);
                if (kvMsg == null)
                    break;
                sequence = kvMsg.getSequence();
                if ("KTHXBAI".equalsIgnoreCase(kvMsg.getKey())) {
                    System.out.println("Received snapshot = " + kvMsg.getSequence());
                    break; // done
                }

                System.out.println("receiving " + kvMsg.getSequence());
                clonecli2.kvMap.put(kvMsg.getKey(), kvMsg);
            }

            // now apply pending updates, discard out-of-getSequence messages
            while (true) {
                kvsimple kvMsg = kvsimple.recv(subscriber);

                if (kvMsg == null)
                    break;

                if (kvMsg.getSequence() > sequence) {
                    sequence = kvMsg.getSequence();
                    System.out.println("receiving " + sequence);
                    clonecli2.kvMap.put(kvMsg.getKey(), kvMsg);
                }
            }
        }
    }

    public static void main(String[] args)
    {
        new clonecli2().run();
    }
}