Send data from android bluetooth to PC with bluecove

Miguel Ribeiro picture Miguel Ribeiro · May 14, 2011 · Viewed 15k times · Source

I'm trying to send data from android (using API from its SDK) to a PC using Bluecove on windows, being this last one the server.

I can get the android to connect to the server but when I write to the socket's output stream, nothing happens on server. I have the onPut method overriden but it is never called.

Code follows bellow, if anyone could help me I would be very appreciated :

Android

public class BluetoothWorker {

private static UUID generalUuid = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");

private static BluetoothSocket socket;


private static BluetoothSocket getBluetoothSocket(){

    BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
    mBluetoothAdapter.cancelDiscovery();
    Set<BluetoothDevice> pairedDevices = mBluetoothAdapter.getBondedDevices();
    // If there are paired devices
    if (pairedDevices.size() > 0) {
        // Loop through paired devices
        for (BluetoothDevice device : pairedDevices) {
            // Add the name and address to an array adapter to show in a ListView
            if(device.getName().equalsIgnoreCase(("MIGUEL-PC"))){
                try {
                    return device.createRfcommSocketToServiceRecord(generalUuid);
                } catch (IOException e) {
                    return null;
                }
            }
        }
    }
    return null;
}

public static boolean sendData(String status){

        socket = getBluetoothSocket();
        try {
            socket.connect();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            socket = null;
        }

    if(socket != null){
        try {       

            socket.getOutputStream().write(status.getBytes());
            socket.getOutputStream().flush();
            socket.close();
            return true;
        } catch (IOException e) {
            socket = null;
            return false;
        }
    }else{
        return false;
    }
}
}

PC code

public class AISHIntegrationBTBridge {

static final String serverUUID = "0000110100001000800000805F9B34FB";

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);
            }

            InputStream is = op.openInputStream();

            StringBuffer buf = new StringBuffer();
            int data;
            while ((data = is.read()) != -1) {
                buf.append((char) data);
            }

            System.out.println("got:" + buf.toString());

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

Answer

Victor Wong picture Victor Wong · Oct 21, 2011

I have done similar thing 2 years ago.

For Android, my code is slightly different from yours:

BluetoothSocket socket = Device.createRfcommSocketToServiceRecord(device_UUID);
socket.connect();
DataOutputStream dos = new DataOutputStream(socket.getOutputStream());

dos.writeChar('x'); // for example

socket.close();

I used DataOutputStream to send data to PC. But surely this doesn't matter, just for your reference.

For PC,

LocalDevice localDevice = LocalDevice.getLocalDevice();

localDevice.setDiscoverable(DiscoveryAgent.GIAC); // Advertising the service

String url = "btspp://localhost:" + device_UUID + ";name=BlueToothServer";
StreamConnectionNotifier server = (StreamConnectionNotifier) Connector.open(url);

StreamConnection connection = server.acceptAndOpen(); // Wait until client connects
//=== At this point, two devices should be connected ===//
DataInputStream dis = connection.openDataInputStream();

char c;
while (true) {
    c = dis.readChar();
    if (c == 'x')
        break;
}

connection.close();

I am not sure if the above codes still work today, as this was done 2 years ago. The BlueCove API may have changed a lot. But anyway, these codes work for me. Hope this may help you.

One more note is that, I had to uninstall the Toshiba Bluetooth Driver in my PC and reinstall the Microsoft one in order to make use of BlueCove. Otherwise, it won't work. (However, latest version of BlueCove may have already supported different drivers, please correct me if I said anything wrong.)