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Asked: 2026-05-27T05:25:32+00:00

I need to write some kind of client-server application using bluetooth. I need to

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I need to write some kind of client-server application using bluetooth. I need to create some server on my laptop (I use java and bluecove) which will be send some data to application (on android). Here is my code:

server: 

public class OBEXPutServer {

static final String serverUUID = "11111111111111111111111111111123";

public static void main(String[] args) throws IOException {

    LocalDevice.getLocalDevice().setDiscoverable(DiscoveryAgent.GIAC);

    SessionNotifier serverConnection = (SessionNotifier) Connector.open("btgoep://localhost:"
            + serverUUID + ";name=ObexExample");

    int count = 0;
    while(count < 2) {
        RequestHandler handler = new RequestHandler();
        serverConnection.acceptAndOpen(handler);
        System.out.println("Received OBEX connection " + (++count));
    }
}

private static class RequestHandler extends ServerRequestHandler {

    public int onPut(Operation op) {
        try {
            HeaderSet hs = op.getReceivedHeaders();
            String name = (String) hs.getHeader(HeaderSet.NAME);
            if (name != null) {
                System.out.println("put name:" + name);
            }

            return ResponseCodes.OBEX_HTTP_OK;
        } catch (IOException e) {
            e.printStackTrace();
            return ResponseCodes.OBEX_HTTP_UNAVAILABLE;
        }
    }
}
}

application:

public class BTTestActivity extends Activity {

String dStarted = BluetoothAdapter.ACTION_DISCOVERY_STARTED;
String dFinished = BluetoothAdapter.ACTION_DISCOVERY_FINISHED;
BluetoothAdapter bluetooth = BluetoothAdapter.getDefaultAdapter();
static final String serverUUID = "11111111111111111111111111111123";

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);   

    BroadcastReceiver discoveryResult = new BroadcastReceiver() 
    {
        public void onReceive(Context context, Intent intent) 
        {
            String remoteDeviceName = intent.getStringExtra(BluetoothDevice.EXTRA_NAME);
            BluetoothDevice remoteDevice;

            remoteDevice = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);

            Log.i("@#$%^&*(*&^%$#@#$%^&*(", "WYSWIETLAM");
            Toast.makeText(getApplicationContext(), "Discovered: " + remoteDeviceName + " address " + remoteDevice.getAddress(), Toast.LENGTH_SHORT).show();

            try{
                BluetoothDevice device = bluetooth.getRemoteDevice(remoteDevice.getAddress());
                BluetoothSocket clientSocket = device.createRfcommSocketToServiceRecord(UUID.fromString(serverUUID));
                clientSocket.connect();

            } catch (IOException e) {
                Log.d("BLUETOOTH", e.getMessage());
            }
        }
    };

    registerReceiver(discoveryResult, new IntentFilter(BluetoothDevice.ACTION_FOUND));
}

public void fun(View view)
{   
    bluetooth.enable();

    if (!bluetooth.isDiscovering())
        bluetooth.startDiscovery();
}

}

My problem is that when I try to connect to service from application I get something like this:

11-26 13:41:04.959: E/AndroidRuntime(8830): FATAL EXCEPTION: main
11-26 13:41:04.959: E/AndroidRuntime(8830): java.lang.RuntimeException: Error receiving broadcast Intent { act=android.bluetooth.device.action.FOUND (has extras) } in andr.andr.BTTestActivity$1@40513e00
11-26 13:41:04.959: E/AndroidRuntime(8830):     at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:722)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at android.os.Handler.handleCallback(Handler.java:587)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at android.os.Handler.dispatchMessage(Handler.java:92)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at android.os.Looper.loop(Looper.java:130)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at android.app.ActivityThread.main(ActivityThread.java:3835)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at java.lang.reflect.Method.invokeNative(Native Method)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at java.lang.reflect.Method.invoke(Method.java:507)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:847)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:605)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at dalvik.system.NativeStart.main(Native Method)
11-26 13:41:04.959: E/AndroidRuntime(8830): Caused by: java.lang.IllegalArgumentException: Invalid UUID: 11111111111111111111111111111133
11-26 13:41:04.959: E/AndroidRuntime(8830):     at java.util.UUID.fromString(UUID.java:226)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at andr.andr.BTTestActivity$1.onReceive(BTTestActivity.java:44)
11-26 13:41:04.959: E/AndroidRuntime(8830):     at android.app.LoadedApk$ReceiverDispatcher$Args.run(LoadedApk.java:709)
11-26 13:41:04.959: E/AndroidRuntime(8830):     ... 9 more

Do anyone know what is wrong with this code? Thanks for any help.

EDIT:

I’ll run this example what you show to me and I run it but its not work 🙁 I have problem wyth server. He is stops on “StreamConnection streamConnection = connectionNotifier.acceptAndOpen();” line in start method. And hare is log from your android app:

11-26 16:08:32.569: D/MyActivity(2725): ON CREATE
11-26 16:08:32.569: D/MyActivity(2725): ON START
11-26 16:08:32.569: D/MyActivity(2725): INSIDE WHILE STATE ON
11-26 16:08:32.589: D/MyActivity(2725): Start discovery = true
11-26 16:08:32.589: D/MyActivity(2725): INSIDE WHILE IS DISCOVERING
11-26 16:08:32.589: D/MyActivity(2725): INSIDE WHILE IS DISCOVERING
11-26 16:08:32.589: D/MyActivity(2725): INSIDE WHILE IS DISCOVERING
11-26 16:08:32.589: D/MyActivity(2725): INSIDE WHILE IS DISCOVERING
11-26 16:08:32.589: D/MyActivity(2725): INSIDE WHILE IS DISCOVERING
11-26 16:08:32.589: D/MyActivity(2725): INSIDE WHILE IS DISCOVERING
11-26 16:08:32.589: D/MyActivity(2725): INSIDE WHILE IS DISCOVERING
11-26 16:08:32.619: D/MyActivity(2725): about to connect
11-26 16:18:18.529: D/MyActivity(3166): Connected!

and when I click button I get in log

11-26 16:19:02.389: D/MyActivity(3166): In listener button.

In your app code I change bluetooth adress to my bluetooth device on laptop. Do you know what is wrong, maybe I need to do something else with your code? And I have a question. Where in yout app code u set UUID of server?

I notice that the log from your app is the same even if I dont run server. Its looks like that the appliaction see only bluetooth adapter on my laptop and dont see server application running on my laptop.

BTW. I use BlueSoleil 6.4.149.0 as my bluetooth stack couse my “Toshiba for windows” stack doesnt work with bluecove. Maybe here is problem?

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1 Answer

  1. Editorial Team

    Try looking at my answer: Why am I losing bluetooth client/server connection?

    You should try using reflection when invoking createRfcommSocket: 

    Method m = bt.getClass().getMethod("createRfcommSocket", new Class[] {int.class});

    I already did a server/client bluetooth connection, and it worked for me. I had similar problems and it turned out to be okay when using reflection.

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