Android: connect to devices via Bluetooth one by one

Question

I use a modification of Android BluetoothChat to connect to devices one by one:

1. try to connect to device
2. if connection was failed then connect to another device
3. if connected then try read data from device and then connect to another device etc.

But I get an exception Service discovery failed on Samsung Galaxy i-9000 (Android 2.3) on a line mmSocket.connect().

The problem is that when I'm using my application on HTC Desire (Android 2.2) it works fine.

But when I added Thread.sleep(...) before socket connection, socket connect always successfully on Samsung and HTC.

Is it problem with Android version or with the code?

Here is the code:

private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
    private final BluetoothDevice mmDevice;
    private boolean mIsCanceled = false;

    public ConnectThread(BluetoothDevice device) {
        mmDevice = device;
        BluetoothSocket tmp = null;

        if(LOG_ENABLED) Log.d(TAG, "create mConnectThread " + mmDevice.getAddress());

        // Get a BluetoothSocket for a connection with the
        // given BluetoothDevice

        try
        {
            tmp = device.createRfcommSocketToServiceRecord(SerialPortServiceClass_UUID);
            if(LOG_ENABLED) Log.d(TAG, "create socket");
        }
        catch (IOException e) {
            if(LOG_ENABLED) Log.e(TAG, "create() failed", e);
        }

        mmSocket = tmp;
    }

    public void run() {
        if(LOG_ENABLED) Log.d(TAG, "run mConnectThread " + mmDevice.getAddress());

        // Always cancel discovery because it will slow down a connection
        mAdapter.cancelDiscovery();

        /*
        With this code commented "mmSocket.connect()" throws an exception
        Service discovery failed on Samsung Galaxy S
        try {
            Thread.sleep(5000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }*/

        if(mIsCanceled) return;

        // Make a connection to the BluetoothSocket
        try {
            // This is a blocking call and will only return on a
            // successful connection or an exception
            if(LOG_ENABLED) Log.d(TAG, "socket.connect() " + mmDevice.getAddress());
            mmSocket.connect();
        } catch (Exception e) {

            if(LOG_ENABLED) Log.e(TAG, e.getMessage() + " " + mmDevice.getAddress(), e);

            try {
                mmSocket.close();
                if(LOG_ENABLED) Log.d(TAG, "mConnectThread mmSocket.close() " + mmDevice.getAddress());
            } catch (IOException e1) {

                if(LOG_ENABLED) Log.e(TAG, "mConnectThread mmSocket.close() error" + mmDevice.getAddress());
                if(LOG_ENABLED) Log.e(TAG, e1.getMessage() + " " + mmDevice.getAddress(), e1);
            }

            connectionFailed(mmDevice.getAddress());

            return;
        }

        // Reset the ConnectThread because we're done
        synchronized (CBluetoothAdapter.this) {
            mConnectThread = null;
        }

        // Start the connected thread
        connected(mmSocket, mmDevice);
    }

    public void cancel() {
        try {
            mmSocket.close();
            if(LOG_ENABLED) Log.d(TAG, "mConnectThread socket close() " + mmDevice.getAddress());
        } catch (IOException e) {
            if(LOG_ENABLED) Log.e(TAG, "mConnectThread close() of connect socket failed " + mmDevice.getAddress(), e);
        }

        mIsCanceled = true;
    }
}

And this is from LogCat:

10-04 12:54:57.035: D/CBluetoothAdapter(27291): Start connect 00:0A:84:02:77:6F
10-04 12:54:57.039: D/CBluetoothAdapter(27291): Connecting to device 00:0A:84:02:77:6F
10-04 12:54:57.039: D/CBluetoothAdapter(27291): connect to: 00:0A:84:02:77:6F
10-04 12:54:57.039: D/CBluetoothAdapter(27291): create mConnectThread 00:0A:84:02:77:6F
10-04 12:54:57.187: D/CBluetoothAdapter(27291): create socket
10-04 12:54:57.187: D/CBluetoothAdapter(27291): State changed: CONNECTING
10-04 12:54:57.191: D/CBluetoothAdapter(27291): run mConnectThread 00:0A:84:02:77:6F
10-04 12:54:57.203: D/CBluetoothAdapter(27291): socket.connect() 00:0A:84:02:77:6F
10-04 12:55:03.234: E/CBluetoothAdapter(27291): Service discovery failed 00:0A:84:02:77:6F
10-04 12:55:03.234: E/CBluetoothAdapter(27291): java.io.IOException: Service discovery failed
10-04 12:55:03.234: E/CBluetoothAdapter(27291):     at     android.bluetooth.BluetoothSocket$SdpHelper.doSdp(BluetoothSocket.java:406)
10-04 12:55:03.234: E/CBluetoothAdapter(27291):     at android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:217)
10-04 12:55:03.234: E/CBluetoothAdapter(27291):     at     scatemobile.adapters.CBluetoothAdapter$ConnectThread.run(CBluetoothAdapter.java:473)
10-04 12:55:03.253: D/CBluetoothAdapter(27291): mConnectThread mmSocket.close() 00:0A:84:02:77:6F
10-04 12:55:03.253: D/CBluetoothAdapter(27291): Connection failed 00:0A:84:02:77:6F
10-04 12:55:03.253: D/CBluetoothAdapter(27291): Disconnect 00:0A:84:02:77:6F
10-04 12:55:03.253: D/CBluetoothAdapter(27291): mConnectThread socket close() 00:0A:84:02:77:6F
10-04 12:55:03.253: D/CBluetoothAdapter(27291): State changed: DISABLED
10-04 12:55:03.253: D/CBluetoothAdapter(27291): Start connect 00:1D:28:92:A2:D1
10-04 12:55:03.257: D/CBluetoothAdapter(27291): Connecting to device 00:1D:28:92:A2:D1
10-04 12:55:03.257: D/CBluetoothAdapter(27291): connect to: 00:1D:28:92:A2:D1
10-04 12:55:03.257: D/CBluetoothAdapter(27291): create mConnectThread 00:1D:28:92:A2:D1
10-04 12:55:03.257: D/CBluetoothAdapter(27291): create socket
10-04 12:55:03.261: D/CBluetoothAdapter(27291): Send msg MSG_CONNECTION_FAILED 00:0A:84:02:77:6F     1079579976
10-04 12:55:03.273: D/CBluetoothAdapter(27291): State changed: CONNECTING
10-04 12:55:03.273: D/CBluetoothAdapter(27291): run mConnectThread 00:1D:28:92:A2:D1
10-04 12:55:03.289: D/CBluetoothAdapter(27291): socket.connect() 00:1D:28:92:A2:D1
10-04 12:55:09.304: E/CBluetoothAdapter(27291): Service discovery failed 00:1D:28:92:A2:D1
10-04 12:55:09.304: E/CBluetoothAdapter(27291): java.io.IOException: Service discovery failed
10-04 12:55:09.304: E/CBluetoothAdapter(27291):     at     android.bluetooth.BluetoothSocket$SdpHelper.doSdp(BluetoothSocket.java:406)
10-04 12:55:09.304: E/CBluetoothAdapter(27291):     at     android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:217)
10-04 12:55:09.304: E/CBluetoothAdapter(27291):     at scatemobile.adapters.CBluetoothAdapter$ConnectThread.run(CBluetoothAdapter.java:473)
10-04 12:55:09.312: D/CBluetoothAdapter(27291): mConnectThread mmSocket.close() 00:1D:28:92:A2:D1
10-04 12:55:09.312: D/CBluetoothAdapter(27291): Connection failed 00:1D:28:92:A2:D1
10-04 12:55:09.316: D/CBluetoothAdapter(27291): Disconnect 00:1D:28:92:A2:D1
10-04 12:55:09.316: D/CBluetoothAdapter(27291): mConnectThread socket close() 00:1D:28:92:A2:D1
10-04 12:55:09.316: D/CBluetoothAdapter(27291): State changed: DISABLED
10-04 12:55:09.316: D/CBluetoothAdapter(27291): Send msg MSG_CONNECTION_FAILED 00:1D:28:92:A2:D1     1079579976
10-04 12:55:09.320: D/CBluetoothAdapter(27291): Start connect 00:0A:84:02:77:70
10-04 12:55:09.324: D/CBluetoothAdapter(27291): Connecting to device 00:0A:84:02:77:70
10-04 12:55:09.324: D/CBluetoothAdapter(27291): connect to: 00:0A:84:02:77:70
10-04 12:55:09.324: D/CBluetoothAdapter(27291): create mConnectThread 00:0A:84:02:77:70
10-04 12:55:09.328: D/CBluetoothAdapter(27291): create socket
10-04 12:55:09.335: D/CBluetoothAdapter(27291): State changed: CONNECTING
10-04 12:55:09.339: D/CBluetoothAdapter(27291): run mConnectThread 00:0A:84:02:77:70
10-04 12:55:09.343: D/CBluetoothAdapter(27291): socket.connect() 00:0A:84:02:77:70
10-04 12:55:15.359: E/CBluetoothAdapter(27291): Service discovery failed 00:0A:84:02:77:70
10-04 12:55:15.359: E/CBluetoothAdapter(27291): java.io.IOException: Service discovery failed
10-04 12:55:15.359: E/CBluetoothAdapter(27291):     at     android.bluetooth.BluetoothSocket$SdpHelper.doSdp(BluetoothSocket.java:406)
10-04 12:55:15.359: E/CBluetoothAdapter(27291):     at     android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:217)
10-04 12:55:15.359: E/CBluetoothAdapter(27291):     at     scatemobile.adapters.CBluetoothAdapter$ConnectThread.run(CBluetoothAdapter.java:473)
10-04 12:55:15.367: D/CBluetoothAdapter(27291): mConnectThread mmSocket.close() 00:0A:84:02:77:70
10-04 12:55:15.367: D/CBluetoothAdapter(27291): Connection failed 00:0A:84:02:77:70
10-04 12:55:15.367: D/CBluetoothAdapter(27291): Disconnect 00:0A:84:02:77:70
10-04 12:55:15.367: D/CBluetoothAdapter(27291): mConnectThread socket close() 00:0A:84:02:77:70
10-04 12:55:15.367: D/CBluetoothAdapter(27291): State changed: DISABLED
10-04 12:55:15.375: D/CBluetoothAdapter(27291): Start connect 00:0A:84:02:5F:3A
10-04 12:55:15.375: D/CBluetoothAdapter(27291): Send msg MSG_CONNECTION_FAILED 00:0A:84:02:77:70 1079579976

Answer 1

I changed my code. Now I use reflection on creating BluetoothSocket:

Method m;

m = device.getClass().getMethod("createRfcommSocket", new Class[]{int.class});
tmp = (BluetoothSocket)m.invoke(device, 1);

And it works for me! Problem solved.