Application closes when socket.bind() is called - JeroMQ on Android

Question

I'm new to programming with Message Queues in general and I've been trying to work on a simple Android Application that uses ZeroMQ. I'm running both server and client program on the same device in separate Threads. This is my Server class:

public class ZeroMQServer implements Runnable{
private Handler uiThreadHandler;

public ZeroMQServer(Handler uiThreadHandler) {
    this.uiThreadHandler = uiThreadHandler;
}

@Override
public void run() {
    ZMQ.Context context = ZMQ.context(1);
    ZMQ.Socket socket = context.socket(ZMQ.REP);
    socket.bind("tcp://*:5570");

    while(!Thread.currentThread().isInterrupted()) {
        byte[] msg = socket.recv(0);
        uiThreadHandler.sendMessage(
                Util.bundledMessage(uiThreadHandler, new String(msg)));
        socket.send(Util.reverseInPlace(msg)+"", 0);
    }
    socket.close();
    context.term();
}

And this is the client class:

public class ZeroMQMessageTask extends AsyncTask<String, Void, String> {
private final Handler uiThreadHandler;

public ZeroMQMessageTask(Handler uiThreadHandler){
    this.uiThreadHandler = uiThreadHandler;
}

@Override
protected String doInBackground(String... params) {
    ZMQ.Context context = ZMQ.context(1);
    ZMQ.Socket socket = context.socket(ZMQ.REQ);
    socket.connect("tcp://localhost:5570");

    socket.send(params[0].getBytes(), 0);
    String result = new String(socket.recv(0));

    socket.close();
    context.term();

    return result;
}

@Override
protected void onPostExecute(String result) {
    uiThreadHandler.sendMessage(Util.bundledMessage(uiThreadHandler, result));
}

And this is the snippet of the main activity that starts the server in another Thread and implements a clickListener to call the client.

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    textView = (TextView)findViewById(R.id.text_console);
    editText = (EditText)findViewById(R.id.text_message);

    new Thread(new ZeroMQServer(serverMessageHandler)).run();

    findViewById(R.id.button_send_message).setOnClickListener(
            new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    new ZeroMQMessageTask(clientMessageHandler).execute(getTaskInput());
                }

                protected String getTaskInput() {
                    return editText.getText().toString();
                }
            });
}

The problem I'm having is that as soon as the application starts it closes automatically. When I remove the socket.bind("tcp://*:5570"); line from the server, it doesn't close anymore, but also doesn't work the way it's supposed to, as the server won't listen.

I have both INTERNET and ACCESS_WIFI_STATE permissions granted in the manifest.

Any help in this matter is appreciated.

EDIT: I've put a breakpoint at the .bind() line, and this is the error I get:

Didn't find class "java.net.StandardProtocolFamily" on path:
  DexPathList[
    [zip file "/data/app/com.example.victor.zeromqrabbitmq-1/base.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_dependencies_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_0_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_1_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_2_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_3_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_4_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_5_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_6_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_7_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_8_apk.apk",
     zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_9_apk.apk"
     ],
  nativeLibraryDirectories=[
     /data/app/com.example.victor.zeromqrabbitmq-1/lib/arm,
     /vendor/lib, /system/lib
     ]
  ]

EDIT2: Full logcat error:

09-01 00:44:19.878 13082-13205/com.example.victor.zeromqrabbitmq E/Error: Exception: 
09-01 00:44:20.188 13082-13205/com.example.victor.zeromqrabbitmq E/AndroidRuntime: FATAL EXCEPTION:
      AsyncTask #1
        Process: com.example.victor.zeromqrabbitmq, PID: 13082
        java.lang.RuntimeException: An error occurred while executing doInBackground()
            at android.os.AsyncTask$3.done(AsyncTask.java:309)
            at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:354)
            at java.util.concurrent.FutureTask.setException(FutureTask.java:223)
            at java.util.concurrent.FutureTask.run(FutureTask.java:242)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
            at java.lang.Thread.run(Thread.java:818)
         Caused by: java.lang.NoClassDefFoundError: Failed resolution of: Ljava/net/StandardProtocolFamily;
            at zmq.io.net.tcp.TcpAddress.family(TcpAddress.java:50)
            at zmq.io.net.tcp.TcpListener.setAddress(TcpListener.java:171)
            at zmq.SocketBase.bind(SocketBase.java:363)
            at org.zeromq.ZMQ$Socket.bind(ZMQ.java:2333)
            at com.example.victor.zeromqrabbitmq.ZeroMQServer.doInBackground(ZeroMQServer.java:24)
            at com.example.victor.zeromqrabbitmq.ZeroMQServer.doInBackground(ZeroMQServer.java:10)
            at android.os.AsyncTask$2.call(AsyncTask.java:295)
            at java.util.concurrent.FutureTask.run(FutureTask.java:237)
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234) 
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113) 
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588) 
            at java.lang.Thread.run(Thread.java:818) 
         Caused by: java.lang.ClassNotFoundException: Didn't find class "java.net.StandardProtocolFamily" on path: DexPathList[[zip file "/data/app/com.example.victor.zeromqrabbitmq-1/base.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_dependencies_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_0_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_1_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_2_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_3_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_4_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_5_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_6_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_7_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_8_apk.apk", zip file "/data/app/com.example.victor.zeromqrabbitmq-1/split_lib_slice_9_apk.apk"],nativeLibraryDirectories=[/data/app/com.example.victor.zeromqrabbitmq-1/lib/arm, /vendor/lib, /system/lib]]
            at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:511)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:469)
            at zmq.io.net.tcp.TcpAddress.family(TcpAddress.java:50) 
            at zmq.io.net.tcp.TcpListener.setAddress(TcpListener.java:171) 
            at zmq.SocketBase.bind(SocketBase.java:363) 
            at org.zeromq.ZMQ$Socket.bind(ZMQ.java:2333) 
            at com.example.victor.zeromqrabbitmq.ZeroMQServer.doInBackground(ZeroMQServer.java:24) 
            at com.example.victor.zeromqrabbitmq.ZeroMQServer.doInBackground(ZeroMQServer.java:10) 
            at android.os.AsyncTask$2.call(AsyncTask.java:295) 
            at java.util.concurrent.FutureTask.run(FutureTask.java:237) 
            at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234) 
            at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113) 
            at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588) 
            at java.lang.Thread.run(Thread.java:818) 
            Suppressed: java.lang.ClassNotFoundException: java.net.StandardProtocolFamily
            at java.lang.Class.classForName(Native Method)
            at java.lang.BootClassLoader.findClass(ClassLoader.java:781)
            at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)
            at java.lang.ClassLoader.loadClass(ClassLoader.java:504)
                    ... 13 more
         Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack trace available
09-01 00:44:20.699 13082-13206/com.example.victor.zeromqrabbitmq E/Surface: getSlotFromBufferLocked: unknown buffer: 0xb810d418

Looks like a simple classNotFound error, but it refers to a class that comes with "android package", meaning it doesn't belong to any external libs. So how could it not be found?

If the app is closing, there should be an error in logcat. Post it. — Gabe Sechan, Aug 31 '17 at 17:47

score 1 · Accepted Answer · answered Sep 13 '17 at 17:20

1

The problem you are running into is the version of JeroMQ you are using isn't compatible with Android. This pull request: https://github.com/zeromq/jeromq/pull/471 added support for Android 10 and above but it only available on 0.4.3-SNAPSHOT.

answered Sep 13 '17 at 17:20

Trevor Bernard

992
10
13

score 0 · Answer 2 · answered Aug 31 '17 at 17:47

0

Maybe remove the * and replace it with localhost

answered Aug 31 '17 at 17:47

IRONALEKS

50
10

user3666197 · Answer 3 · 2017-08-31T21:17:51.153

0

Rule 0) Get used to always use a call to a Poller.poll( aTimeoutInMILLISECONDs ) method, so as to remain in control of what events need to get served ( if any ) within an external event-loop eco-system

Rule 1) Never use REQ/REP in a serious, production-grade code, because of it's inherent hard-wired affinity to fall into an un-salvageable mutual dead-lock.

Rule 2) Always prefer an explicit address .bind()-s. Implicit ones and wildcard expansions are not a way for a curated production-grade deployment, as your system will depend on external translations -- rather .bind() to an explicit and globally advertised address ( even if schoolbook examples show other practices ... )

Rule 3) Do not hesitate to use assert(); or try: / except: handling practice, so that you can well-enough localise and diagnose the root cause of any exception. ZeroMQ error-tools are available in most of the language bindings.

edited Aug 31 '17 at 21:17

answered Aug 31 '17 at 21:07

user3666197

1
6
50
92

Please explain rule 2. Binding servers to 0.0.0.0 is the customary practice and does not depend on external translations. – user207421 Aug 31 '17 at 23:54
ZeroMQ can `.bind()` onto many **`transport-class://address:port`** target-points at once, using a wildcard. While syntax permits doing this, any colliding case remains "masked" / "hidden" behind the "herd". So using an explicit, `.bind()` -target is a way better practice, as an exception handling ( i.e. on a resource-in-use collision et al ) is always a-priori isolated and right on-the-spot to introduce a context-aware exception handler. – user3666197 Sep 01 '17 at 00:50
I was not aware of those practices, since I'm new to MQ's in general. But I'll try to keep that in mind while improving my code. Thanks! – J. Maruca Sep 01 '17 at 03:20

Application closes when socket.bind() is called - JeroMQ on Android

3 Answers3