BluetoothServerSocket accept() not returning on HTC Desire - android-bluetooth

Question

I'm working on a bluetooth-capable application, based on the well-known BluetoothChat example.
Basically with this app a client can send some packets to a server.
I have tested the application using two Xperia smartphones (Xperia X8 and Xperia Sola, android 2.1 and 4.0) and all is working fine: they both can act as client or server.
Unfortunately if I use an HTC Desire (android 2.3) as server, it won't be able to accept incoming connection from one of the Xperia client. It seems that the client connect() returns as if all was fine, but instead the server is blocked on its accept() as if nothing was happened.
Relevant code snippets:
1. "Accept Thread"
private class BluetoothAcceptThread extends Thread
{
private final BluetoothServerSocket serverSocket;
public BluetoothAcceptThread()
{
BluetoothServerSocket tmpSocket = null;
try
{
Method m = bluetoothAdapter.getClass().getMethod("listenUsingRfcommOn", new Class[] {int.class});
tmpSocket = (BluetoothServerSocket) m.invoke(bluetoothAdapter, APP_BT_CHANNEL);
}
catch (NoSuchMethodException e)
{
e.printStackTrace();
}
catch (InvocationTargetException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothAcceptThread listen() (with reflection) failed", e);
}
catch (IllegalAccessException e)
{
e.printStackTrace();
}
serverSocket = tmpSocket;
Log.d(MainActivity.DEBUG_TAG, "BluetoothAcceptThread ServerSocket created");
}
#Override
public void run()
{
BluetoothSocket socket = null;
try
{
Log.d(MainActivity.DEBUG_TAG, "BluetoothAcceptThread calling accept()...");
socket = serverSocket.accept();
Log.d(MainActivity.DEBUG_TAG, "BluetoothAcceptThread accept() returned");
}
catch (IOException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothAcceptThread accept() failed: " + e.getMessage());
}
if (socket != null)
{
Log.d(MainActivity.DEBUG_TAG, "BluetoothAcceptThread accept() successfully");
synchronized (BluetoothManager.this)
{
if (currentState == SocketState.LISTENING || currentState == SocketState.CONNECTING)
startBluetoothConnection(socket); // all is ok, it can proceed
else if (currentState == SocketState.INACTIVE || currentState == SocketState.CONNECTED)
cancel(socket);
}
}
}
#Override
public void cancel()
{
try
{
serverSocket.close();
Log.d(MainActivity.DEBUG_TAG, "BluetoothAcceptThread ServerSocket closed");
}
catch (IOException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothAcceptThread close() failed", e);
}
}
private void cancel(BluetoothSocket newSocket)
{
try
{
newSocket.close();
Log.d(MainActivity.DEBUG_TAG, "BluetoothAcceptThread client socket closed");
}
catch (IOException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothAcceptThread client socket close() failed", e);
}
}
}
2. "Connect thread"
private class BluetoothConnectThread extends Thread
{
private final BluetoothSocket socket;
private final BluetoothDevice device;
public BluetoothConnectThread(BluetoothDevice d)
{
device = d;
BluetoothSocket tmpSocket = null;
try
{
Method m = device.getClass().getMethod("createRfcommSocket", new Class[] {int.class});
tmpSocket = (BluetoothSocket) m.invoke(device, APP_BT_CHANNEL);
}
catch (NoSuchMethodException e)
{
e.printStackTrace();
}
catch (InvocationTargetException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothConnectThread create() (with reflection) failed", e);
}
catch (IllegalAccessException e)
{
e.printStackTrace();
}
socket = tmpSocket;
Log.d(MainActivity.DEBUG_TAG, "BluetoothConnectThread client socket created");
}
#Override
public void run()
{
stopBluetoothDiscovery(); // otherwise it will slow down the connection
try
{
socket.connect();
Log.d(MainActivity.DEBUG_TAG, "BluetoothConnectThread connect() successfully");
}
catch (IOException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothConnectThread connect() failed", e);
String deviceName = device != null ? device.getName() : "none";
connectionFailed(deviceName); // notify UI thread
return;
}
synchronized (BluetoothManager.this)
{
bluetoothConnectThread = null;
}
startBluetoothConnection(socket); // create the "Communication" Thread
}
#Override
public void cancel()
{
try
{
socket.close();
Log.d(MainActivity.DEBUG_TAG, "BluetoothConnectThread client socket closed");
}
catch (IOException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothConnectThread close() failed", e);
}
}
}
3. "Communication Thread" (aka ConnectedThread in BluetoothChat sample)
private class BluetoothCommunicationThread extends Thread
{
private final BluetoothSocket socket;
private final InputStream inputStream;
private final OutputStream outputStream;
public BluetoothCommunicationThread(BluetoothSocket s)
{
socket = s;
InputStream in = null;
OutputStream out = null;
try
{
in = socket.getInputStream();
out = socket.getOutputStream();
}
catch (IOException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothCommunicationThread failed to get streams", e);
}
inputStream = in;
outputStream = out;
}
#Override
public void run()
{
byte[] buffer = new byte[BT_BUFF_SIZE];
int readBytes;
while (true)
{
try
{
readBytes = inputStream.read(buffer, 0, buffer.length);
if (readBytes != -1)
{
Message message = messageHandler.obtainMessage(DATA_MSG, readBytes, -1, buffer);
message.sendToTarget(); // notify to UI thread the bytes counter
}
else
{
BluetoothDevice device = socket.getRemoteDevice();
String deviceName = device != null ? device.getName() : "none";
connectionLost(deviceName);
break;
}
}
catch (IOException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothCommunicationThread read() failed", e);
BluetoothDevice device = socket.getRemoteDevice();
String deviceName = device != null ? device.getName() : "none";
connectionLost(deviceName);
break;
}
}
}
public void write(byte[] buffer)
{
try
{
outputStream.write(buffer);
}
catch (IOException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothCommunicationThread write() failed", e);
}
}
#Override
public void cancel()
{
try
{
socket.close();
Log.d(MainActivity.DEBUG_TAG, "BluetoothCommunicationThread socket closed");
}
catch (IOException e)
{
Log.e(MainActivity.ERROR_TAG, "BluetoothCommunicationThread close() failed", e);
}
}
}
So the steps of the problem are the following:
HTC Desire server calls accept()
Xperia client calls connect()
The connect returns as if the connection was established
Nothing is happening on the HTC, always blocked on accept()
Xperia client thinks that it's connected, so it creates the CommunicationThread and calls the blocking read(); this function throws java.io.IOException: Software caused connection abort, probably because the socket is not connected.
Finally these are the relevant logcats:
Xperia client:
09-20 00:44:23.562 9106-9106/com.powertester D/[PowerTester Debug]﹕ BluetoothConnectThread client socket created
09-20 00:44:25.704 9106-9579/com.powertester D/[PowerTester Debug]﹕ BluetoothConnectThread connect() successfully
09-20 00:44:25.734 9106-9579/com.powertester D/[PowerTester Debug]﹕ BluetoothCommunicationThread started and I/O streams ready
09-20 00:44:25.764 9106-9589/com.powertester E/[PowerTester Error]﹕ BluetoothCommunicationThread read() failed
java.io.IOException: Software caused connection abort
at android.bluetooth.BluetoothSocket.readNative(Native Method)
at android.bluetooth.BluetoothSocket.read(BluetoothSocket.java:333)
at android.bluetooth.BluetoothInputStream.read(BluetoothInputStream.java:96)
at com.powertester.net.BluetoothManager$BluetoothCommunicationThread.run(BluetoothManager.java:518)
09-20 00:44:25.844 9106-9106/com.powertester D/[PowerTester Debug]﹕ BluetoothCommunicationThread socket closed
HTC server:
09-19 15:47:07.591 2422-2422/com.powertester D/[PowerTester Debug]﹕ BluetoothAcceptThread ServerSocket created
09-19 15:47:07.591 2422-2484/com.powertester D/[PowerTester Debug]﹕ BluetoothAcceptThread calling accept()...
The really strange thing is that the HTC Desire works if used as client with one of the Xperia used as server.
So, is a problem of my app or a problem in the HTC Desire bluetooth stack?

Answer 1

After some troubles I have realized that the problem is the reflection itself and the explicit use of a Bluetooth Channel.
Using the normal way (i.e. the not-hidden bluetooth methods) my app works perfectly.