Java ZFrame类代码示例

import org.zeromq.ZFrame; //导入依赖的package包/类
public static String[] gunzipMultifameZMsg(ZMsg msg) throws IOException {
	Iterator<ZFrame> frames = msg.iterator();
	// pop off first frame, which contains "/GOVI/KV8" (the feed name)
	// (isn't there a method for this?)
	String header = frames.next().toString();
	ByteArrayOutputStream buffer = new ByteArrayOutputStream();
	while (frames.hasNext()) {
		ZFrame frame = frames.next();
		byte[] frameData = frame.getData();
		buffer.write(frameData);
	}
	if (buffer.size() == 0) {
		return null;
	}
	// chain input streams to gunzip contents of byte buffer
	InputStream gzippedMessageStream = new ByteArrayInputStream(
			buffer.toByteArray());
	InputStream messageStream = new GZIPInputStream(gzippedMessageStream);
	// copy input stream back to transport stream
	buffer.reset();
	byte[] b = new byte[4096];
	for (int n; (n = messageStream.read(b)) != -1;) {
		buffer.write(b, 0, n);
	}
	return new String[] { header, buffer.toString() };
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
/**
 * Block until a message can be read
 * 
 * @return
 * @throws IOException
 */
public Envelope receive(long timeout) throws IOException {

	ZMQ.poll(items, timeout);
	if (items[0].isReadable()) {
		// System.out.println("Receiving");
		// The DEALER socket gives us the address envelope and message
		ZMsg msg = ZMsg.recvMsg(socket);
		// System.out.println("Recvd " + msg);
		ZFrame content = msg.getLast();
		assert (content != null);
		// System.out.println("Content " + content);

		return Envelope.parseFrom(content.getData());
	} else
		return null; // timed out
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
/**
 * Send message to broker If no msg is provided, creates one internally
 *
 * @param command
 * @param option
 * @param msg
 */
void sendToBroker(MDP command, String option, ZMsg msg) {
    msg = msg != null ? msg.duplicate() : new ZMsg();

    // Stack protocol envelope to start of message
    if (option != null)
        msg.addFirst(new ZFrame(option));

    msg.addFirst(command.newFrame());
    msg.addFirst(MDP.W_WORKER.newFrame());
    msg.addFirst(new ZFrame(ZMQ.MESSAGE_SEPARATOR));

    if (verbose) {
        log.format("I: sending %s to broker\n", command);
        msg.dump(log.out());
    }
    msg.send(worker);
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
@Override
public void run (Object ... args)
{
    ZContext context = new ZContext();

    //  Prepare our context and sockets
    Socket worker  = context.createSocket (ZMQ.REQ);
    ZHelper.setId (worker);     //  Set a printable identity

    worker.connect("ipc://backend.ipc");

    //  Tell backend we're ready for work
    ZFrame frame = new ZFrame (WORKER_READY);
    frame.send (worker, 0);

    while(true)
    {
        ZMsg msg = ZMsg.recvMsg (worker);
        if (msg == null)
            break;

        msg.getLast ().reset ("OK");
        msg.send (worker);
    }
    context.destroy ();
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
static ZMsg
serviceCall (mdcliapi session, String service, ZMsg request)
{
    ZMsg reply = session.send(service, request);
    if (reply != null) {
        ZFrame status = reply.pop();
        if (status.streq("200")) {
            status.destroy();
            return reply;
        }
        else if (status.streq("400")) {
            System.out.println("E: client fatal error, aborting");
        }
        else
        if (status.streq("500")) {
            System.out.println("E: server fatal error, aborting");
        }
        reply.destroy();
    }
    return null;        //  Didn't succeed; don't care why not
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
@Override
public int handle(ZLoop loop, PollItem item, Object arg_) {

    LBBroker arg = (LBBroker)arg_;
    ZMsg msg = ZMsg.recvMsg(arg.backend);
    if (msg != null) {
        ZFrame address = msg.unwrap();
        //  Queue worker address for load-balancing
        arg.workers.add(address);

        //  Enable reader on frontend if we went from 0 to 1 workers
        if (arg.workers.size() == 1) {
            PollItem newItem = new PollItem (arg.frontend, ZMQ.Poller.POLLIN);
            loop.addPoller (newItem, frontendHandler, arg);
        }

        //  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(arg.frontend);
    }
    return 0;
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
@Override
public void run()
{
    ZContext ctx = new ZContext();
    Socket worker = ctx.createSocket(ZMQ.REQ);
    worker.connect(String.format("ipc://%s-localbe.ipc", self));

    //  Tell broker we're ready for work
    ZFrame frame = new ZFrame(WORKER_READY);
    frame.send(worker, 0);

    while (true) {
        //  Send request, get reply
        ZMsg msg = ZMsg.recvMsg(worker, 0);
        if (msg == null)
            break;              //  Interrupted
        msg.getLast().print("Worker: ");
        msg.getLast().reset("OK");
        msg.send(worker);

    }
    ctx.destroy();
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
public void run()
{
    ZContext context = new ZContext();
    //  Prepare our context and sockets
    Socket worker = context.createSocket(ZMQ.REQ);

    worker.connect("ipc://backend.ipc");

    ZFrame frame = new ZFrame(lruqueue3.LRU_READY);
    //  Tell backend we're ready for work
    frame.send(worker, 0);

    while (true) {
        ZMsg msg = ZMsg.recvMsg(worker);
        if (msg == null)
            break;

        msg.getLast().reset("OK".getBytes(ZMQ.CHARSET));

        msg.send(worker);
        System.out.println(Thread.currentThread().getName() + " Worker Sent OK");
    }

    context.destroy();
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
@Override
public int handle(ZLoop loop, PollItem item, Object arg_)
{

    LRUQueueArg arg = (LRUQueueArg) arg_;
    ZMsg msg = ZMsg.recvMsg(arg.backend);
    if (msg != null) {
        ZFrame address = msg.unwrap();
        //  Queue worker address for LRU routing
        arg.workers.add(address);

        //  Enable reader on frontend if we went from 0 to 1 workers
        if (arg.workers.size() == 1) {
            PollItem poller = new PollItem(arg.frontend, ZMQ.Poller.POLLIN);
            loop.addPoller(poller, lruqueue3.handle_frontend, arg);
        }

        //  Forward message to client if it's not a READY
        ZFrame frame = msg.getFirst();
        if (new String(frame.getData(), ZMQ.CHARSET).equals(lruqueue3.LRU_READY))
            msg.destroy();
        else
            msg.send(arg.frontend);
    }
    return 0;
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
/**
 * 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);
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
/**
 * Send message to worker. If message is provided, sends that message. Does
 * not destroy the message, this is the caller's job.
 */
public void sendToWorker(Worker worker, MDP command, String option,
        ZMsg msgp) {

    ZMsg msg = msgp == null ? new ZMsg() : msgp.duplicate();

    // Stack protocol envelope to start of message
    if (option != null)
        msg.addFirst(new ZFrame(option));
    msg.addFirst(command.newFrame());
    msg.addFirst(MDP.W_WORKER.newFrame());

    // Stack routing envelope to start of message
    msg.wrap(worker.address.duplicate());
    if (verbose) {
        log.format("I: sending %s to worker\n", command);
        msg.dump(log.out());
    }
    msg.send(socket);
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
private Message readMessage(ZMQ.Socket socket) {
  ZMsg zmsg = null;
  Message message = new Message();
  try {
    zmsg = ZMsg.recvMsg(socket);
    ZFrame[] parts = new ZFrame[zmsg.size()];
    zmsg.toArray(parts);
    byte[] uuid = parts[MessageParts.UUID].getData();
    byte[] header = parts[MessageParts.HEADER].getData();
    byte[] parent = parts[MessageParts.PARENT].getData();
    byte[] metadata = parts[MessageParts.METADATA].getData();
    byte[] content = parts[MessageParts.CONTENT].getData();
    byte[] expectedSig = parts[MessageParts.HMAC].getData();

    verifyDelim(parts[MessageParts.DELIM]);
    verifySignatures(expectedSig, header, parent, metadata, content);

    if (uuid != null) {
      message.getIdentities().add(uuid);
    }
    message.setHeader(parse(header, Header.class));
    message.setParentHeader(parse(parent, Header.class));
    message.setMetadata(parse(metadata, LinkedHashMap.class));
    message.setContent(parse(content, LinkedHashMap.class));

  } finally {
    if (zmsg != null) {
      zmsg.destroy();
    }
  }

  return message;
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
private String verifyDelim(ZFrame zframe) {
  String delim = new String(zframe.getData(), StandardCharsets.UTF_8);
  if (!DELIM.equals(delim)) {
    throw new RuntimeException("Delimiter <IDS|MSG> not found");
  }
  return delim;
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
/**
 * Expect multipart message at least three parts:
 *
 * 0       envelope frame         -> envelope[N-4]
 * ...
 * N-4     envelope frame         -> envelope[0]
 * N-3     Empty Delimiter Frame
 * N-2     Serialized callback ID -> callbackId
 * N-1     Serialized payload     -> payload
 *
 * @param message input
 * @throws TransferHelper.ProtocolException if protocol is violated
 */
public TransferWrapperRaw(ZMsg message) throws TransferHelper.ProtocolException {
    if (message == null) { throw new IllegalArgumentException(); }
    int N = message.size();

    if (N <= 2) {
        throw new TransferHelper.ProtocolException("Wrong number of Frames. Expected lower than 3: " + message.size());
    }

    ZFrame payloadFrame = message.pollLast();
    ZFrame callbackFrame = message.pollLast();
    ZFrame delimiterFrame = message.pollLast();

    if (delimiterFrame.size() != 0) {
        throw new TransferHelper.ProtocolException("Delimiter frame not empty.");
    }

    callbackId = TransferHelper.bytes2int(callbackFrame.getData());

    payload = payloadFrame.getData();

    envelope = new ZFrame[N-3];
    for(int i = 0; i < N-3; i++) {
        envelope[i] = message.pollLast();
    }

    if (message.size() != 0) throw new IllegalStateException("Message not empty.");
}
 

import org.zeromq.ZFrame; //导入依赖的package包/类
/**
 * Inverse to ZMsg constructor.
 *
 * @return message
 */
public ZMsg toMessage() {
    ZMsg out = new ZMsg();

    out.addFirst(payload);
    out.addFirst(TransferHelper.int2bytes(callbackId));
    out.addFirst(new byte[0]);

    for (ZFrame f : envelope){
        out.addFirst(f);
    }

    return out;
}