Merge pull request booksbyus#180 from acogoluegnes/java-mthwserver

Added Java-based multithreaded service sample

examples/Java/mthwserver.java

@@ -0,0 +1,72 @@
+//
+//  Multithreaded Hello World server in Java
+//
+//  Arnaud Cogoluègnes <acogoluegnes@gmail.com>
+//
+import org.zeromq.ZMQ;
+import org.zeromq.ZMQ.Context;
+import org.zeromq.ZMQQueue;
+
+public class mthwserver {
+
+	private static final class WorkerThread extends Thread {
+
+		private final ZMQ.Context context;		
+
+		public WorkerThread(Context context) {
+			super();
+			this.context = context;
+		}
+
+		@Override
+		public void run() {
+			ZMQ.Socket receiver = context.socket(ZMQ.REP);
+			receiver.connect("inproc://workers");
+			while(!Thread.currentThread().isInterrupted()) {
+				byte[] request = receiver.recv (0);
+	            //  In order to display the 0-terminated string as a String,
+	            //  we omit the last byte from request
+	            System.out.println ("Received request: [" +
+	            new String(request,0,request.length-1)  //  Creates a String from request, minus the last byte
+	            + "]");
+
+	            //  Do some 'work'
+	            try {
+	                Thread.sleep (1000);
+	            }
+	            catch(InterruptedException e){
+	                e.printStackTrace();
+	            }
+
+	            //  Send reply back to client
+	            //  We will send a 0-terminated string (C string) back to the client,
+	            //  so that this server also works with The Guide's C and C++ "Hello World" clients
+	            String replyString = "World" + " ";
+	            byte[] reply = replyString.getBytes();
+	            reply[reply.length-1]=0; //Sets the last byte of the reply to 0
+	            receiver.send(reply, 0);
+			}
+		}
+
+	}
+
+    public static void main(String[] args) {
+        //  Prepare our context and socket
+        ZMQ.Context context = ZMQ.context(1);
+        // Socket to talk to clients
+        ZMQ.Socket clients = context.socket(ZMQ.ROUTER);
+        clients.bind("tcp://*:5555");
+
+        // Socket to talk to workers
+        ZMQ.Socket workers = context.socket(ZMQ.DEALER);
+        workers.bind("inproc://workers");
+
+        // Launch worker threads
+        for(int threadNb = 0;threadNb < 5; threadNb++) {
+        	new WorkerThread(context).start();
+        }
+        // Connect work threads to client threads via a queue
+        ZMQQueue queue = new ZMQQueue(context, clients, workers);
+        new Thread(queue).start();
+    }
+}