Examples with ZFrame org.zeromq.ZFrame used on opensource projects

Example 1 with ZFrame

use of org.zeromq.ZFrame in project jeromq by zeromq.

the class lbbroker2 method main.

/**
     * This is the main task. This has the identical functionality to
     * the previous lbbroker example but uses higher level classes to start child threads
     * to hold the list of workers, and to read and send messages:
     */
public static void main(String[] args) {
    ZContext context = new ZContext();
    //  Prepare our context and sockets
    Socket frontend = context.createSocket(ZMQ.ROUTER);
    Socket backend = context.createSocket(ZMQ.ROUTER);
    frontend.bind("ipc://frontend.ipc");
    backend.bind("ipc://backend.ipc");
    int clientNbr;
    for (clientNbr = 0; clientNbr < NBR_CLIENTS; clientNbr++) ZThread.start(new ClientTask());
    for (int workerNbr = 0; workerNbr < NBR_WORKERS; workerNbr++) ZThread.start(new WorkerTask());
    //  Queue of available workers
    Queue<ZFrame> workerQueue = new LinkedList<ZFrame>();
    while (!Thread.currentThread().isInterrupted()) {
        //  Initialize poll set
        Poller items = context.createPoller(2);
        //  Always poll for worker activity on backend
        items.register(backend, Poller.POLLIN);
        //  Poll front-end only if we have available workers
        if (workerQueue.size() > 0)
            items.register(frontend, Poller.POLLIN);
        if (items.poll() < 0)
            //  Interrupted
            break;
        //  Handle worker activity on backend
        if (items.pollin(0)) {
            ZMsg msg = ZMsg.recvMsg(backend);
            if (msg == null)
                //  Interrupted
                break;
            ZFrame identity = msg.unwrap();
            //  Queue worker address for LRU routing
            workerQueue.add(identity);
            //  Forward message to client if it's not a READY
            ZFrame frame = msg.getFirst();
            if (Arrays.equals(frame.getData(), WORKER_READY))
                msg.destroy();
            else
                msg.send(frontend);
        }
        if (items.pollin(1)) {
            //  Get client request, route to first available worker
            ZMsg msg = ZMsg.recvMsg(frontend);
            if (msg != null) {
                msg.wrap(workerQueue.poll());
                msg.send(backend);
            }
        }
    }
    context.destroy();
}

Example 2 with ZFrame

use of org.zeromq.ZFrame in project jeromq by zeromq.

the class lruqueue3 method main.

public static void main(String[] args) {
    ZContext context = new ZContext();
    LRUQueueArg arg = new LRUQueueArg();
    //  Prepare our context and sockets
    Socket frontend = context.createSocket(ZMQ.ROUTER);
    Socket backend = context.createSocket(ZMQ.ROUTER);
    arg.frontend = frontend;
    arg.backend = backend;
    frontend.bind("ipc://frontend.ipc");
    backend.bind("ipc://backend.ipc");
    int client_nbr;
    for (client_nbr = 0; client_nbr < 10; client_nbr++) new ClientThread3().start();
    int worker_nbr;
    for (worker_nbr = 0; worker_nbr < 3; worker_nbr++) new WorkerThread3().start();
    //  Queue of available workers
    arg.workers = new LinkedList<ZFrame>();
    //  Prepare reactor and fire it up
    ZLoop reactor = new ZLoop(context);
    reactor.verbose(true);
    PollItem poller = new PollItem(arg.backend, ZMQ.Poller.POLLIN);
    reactor.addPoller(poller, handle_backend, arg);
    reactor.start();
    reactor.destroy();
    for (ZFrame frame : arg.workers) {
        frame.destroy();
    }
    context.destroy();
    System.exit(0);
}

Example 3 with ZFrame

use of org.zeromq.ZFrame in project jeromq by zeromq.

the class lvcache method main.

public static void main(String[] args) {
    ZContext context = new ZContext();
    Socket frontend = context.createSocket(ZMQ.SUB);
    frontend.bind("tcp://*:5557");
    Socket backend = context.createSocket(ZMQ.XPUB);
    backend.bind("tcp://*:5558");
    //  Subscribe to every single topic from publisher
    frontend.subscribe(ZMQ.SUBSCRIPTION_ALL);
    //  Store last instance of each topic in a cache
    Map<String, String> cache = new HashMap<String, String>();
    Poller poller = context.createPoller(2);
    poller.register(frontend, Poller.POLLIN);
    poller.register(backend, Poller.POLLIN);
    //  if anything:
    while (true) {
        if (poller.poll(1000) == -1)
            //  Interrupted
            break;
        //  Any new topic data we cache and then forward
        if (poller.pollin(0)) {
            String topic = frontend.recvStr();
            String current = frontend.recvStr();
            if (topic == null)
                break;
            cache.put(topic, current);
            backend.sendMore(topic);
            backend.send(current);
        }
        //  When we get a new subscription, we pull data from the cache:
        if (poller.pollin(1)) {
            ZFrame frame = ZFrame.recvFrame(backend);
            if (frame == null)
                break;
            //  Event is one byte 0=unsub or 1=sub, followed by topic
            byte[] event = frame.getData();
            if (event[0] == 1) {
                String topic = new String(event, 1, event.length - 1, ZMQ.CHARSET);
                System.out.printf("Sending cached topic %s\n", topic);
                String previous = cache.get(topic);
                if (previous != null) {
                    backend.sendMore(topic);
                    backend.send(previous);
                }
            }
            frame.destroy();
        }
    }
    context.destroy();
}

Example 4 with ZFrame

use of org.zeromq.ZFrame in project jeromq by zeromq.

the class mdbroker method serviceInternal.

/**
     * Handle internal service according to 8/MMI specification
     */
private void serviceInternal(ZFrame serviceFrame, ZMsg msg) {
    String returnCode = "501";
    if ("mmi.service".equals(serviceFrame.toString())) {
        String name = msg.peekLast().toString();
        returnCode = services.containsKey(name) ? "200" : "400";
    }
    msg.peekLast().reset(returnCode.getBytes(ZMQ.CHARSET));
    // Remove & save client return envelope and insert the
    // protocol header and service name, then rewrap envelope.
    ZFrame client = msg.unwrap();
    msg.addFirst(serviceFrame.duplicate());
    msg.addFirst(MDP.C_CLIENT.newFrame());
    msg.wrap(client);
    msg.send(socket);
}

Example 5 with ZFrame

use of org.zeromq.ZFrame in project jeromq by zeromq.

the class mdcliapi method send.

/**
     * Send request to broker and get reply by hook or crook Takes ownership of
     * request message and destroys it when sent. Returns the reply message or
     * NULL if there was no reply.
     *
     * @param service
     * @param request
     * @return
     */
public ZMsg send(String service, ZMsg request) {
    request.push(new ZFrame(service));
    request.push(MDP.C_CLIENT.newFrame());
    if (verbose) {
        log.format("I: send request to '%s' service: \n", service);
        request.dump(log.out());
    }
    ZMsg reply = null;
    int retriesLeft = retries;
    while (retriesLeft > 0 && !Thread.currentThread().isInterrupted()) {
        request.duplicate().send(client);
        // Poll socket for a reply, with timeout
        ZMQ.Poller items = ctx.createPoller(1);
        items.register(client, ZMQ.Poller.POLLIN);
        if (items.poll(timeout) == -1)
            // Interrupted
            break;
        if (items.pollin(0)) {
            ZMsg msg = ZMsg.recvMsg(client);
            if (verbose) {
                log.format("I: received reply: \n");
                msg.dump(log.out());
            }
            // Don't try to handle errors, just assert noisily
            assert (msg.size() >= 3);
            ZFrame header = msg.pop();
            assert (MDP.C_CLIENT.equals(header.toString()));
            header.destroy();
            ZFrame replyService = msg.pop();
            assert (service.equals(replyService.toString()));
            replyService.destroy();
            reply = msg;
            break;
        } else {
            items.unregister(client);
            if (--retriesLeft == 0) {
                log.format("W: permanent error, abandoning\n");
                break;
            }
            log.format("W: no reply, reconnecting\n");
            reconnectToBroker();
        }
    }
    request.destroy();
    return reply;
}