I try to set up a Bluetooth connection as follows:
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
BluetoothSocket connection = null;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
if(D)
Log.i(TAG, "createRfcommSocket");
Method m = mmDevice.getClass().getMethod("createRfcommSocket", new Class[] { int.class });
connection = (BluetoothSocket) m.invoke(mmDevice, 1);
Utils.pause(100);
} catch (Exception e) {
Log.e(TAG, "create() failed", e);
}
if(D)
Log.i(TAG, "Bluetooth socket initialised");
mmSocket = connection;
}
public void run() {
if(D)
Log.i(TAG, "BEGIN mConnectThread on Device: " + mmDevice);
setName("ConnectThread");
if (mmSocket != null) {
// Always cancel discovery because it will slow down a connection
if(mAdapter.isDiscovering()) {
if(D)
Log.i(TAG, "stop discovering before trying to connect");
mAdapter.cancelDiscovery();
}
// Make a connection to the BluetoothSocket
try {
// This is a blocking call and will only return on a
// successful connection or an exception
if(D)
Log.i(TAG, "start Bluetooth socket connection");
mmSocket.connect();
if(D)
Log.i(TAG, "end of Bluetooth socket connection");
} catch (Exception e1) {
Log.e(TAG, "connect failed", e1);
connectionFailed();
// Reset the socket
resetConnection(mmSocket);
// Start the service over to restart listening mode
if(D)
Log.i(TAG, "restart connection");
BluetoothConnectionService.this.start();
if(D)
Log.i(TAG, "return");
return;
}
// Start the connected thread
if(D)
Log.i(TAG, "The device is considered as connected, call connected thread");
connected(mmSocket, mmDevice);
} else {
if(D)
Log.i(TAG, "connection fail");
connectionFailed();
BluetoothConnectionService.this.start();
}
}
public void cancel() {
if(D)
Log.i(TAG, "connect thread cancel");
resetConnection(mmSocket);
}
}
The connection seems to be OK, and I get this log:
DEBUG/BluetoothConnectionService(3439): **connect to: 00:18:E4:21:8B:5E**
INFO/BluetoothConnectionService(3439): createRfcommSocket
INFO/BluetoothConnectionService(3439): Bluetooth socket initialised
INFO/BluetoothConnectionService(3439): BEGIN mConnectThread on Device : 00:18:E4:21:8B:5E
INFO/BluetoothConnectionService(3439): **start Bluetooth socket connection**
INFO/BluetoothConnectionService(3439): setState() 1 -> 2
INFO/ProtectionService(3439): MESSAGE_STATE_CHANGE: 1
DEBUG/ProtectionService(3439): STATE_CHANGED to STATE_LISTEN
INFO/ProtectionService(3439): MESSAGE_STATE_CHANGE: 2
DEBUG/abtfilt(2772): **Conn complete**
INFO/bluetoothd(2776): link_key_request (sba=24:21:AB:F4:69:25, dba=00:18:E4:21:8B:5E)
INFO/bluetoothd(2776): link_key_request (sba=24:21:AB:F4:69:25, dba=00:18:E4:21:8B:5E)
INFO/BluetoothConnectionService(3439): **end of Bluetooth socket connection**
INFO/BluetoothConnectionService(3439): **The device is considered as connected, call connected thread**
The BluetoothSocket.connect() returns without error.
Then I manage the connection with this:
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
if(D) Log.d(TAG, "create ConnectedThread");
mmSocket = socket;
// Get the BluetoothSocket input and output streams
try {
if(D)
Log.i(TAG, "Get input stream");
tmpIn = socket.getInputStream();
if(D)
Log.i(TAG, "Get output stream");
tmpOut = socket.getOutputStream();
if(D)
Log.i(TAG, "isConnected = true");
isConnected = true;
} catch (IOException e) {
Log.e(TAG, "Input and Output sockets not created", e);
isConnected = false;
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
if(D)
Log.i(TAG, "BEGIN mConnectedThread");
byte[] buffer = new byte[1024]; //buffer store for the stream
int bytes; //bytes returned from read()
// Keep listening to the InputStream until an exception occurs
while(true) {
try {
// Read from the InputStream
if(D)
Log.i(TAG, "start read mmInStream");
bytes = mmInStream.read(buffer);
if(D)
Log.i(TAG, "Bytes read: " + bytes);
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(MESSAGE_READ, bytes, -1, buffer).sendToTarget();
} catch (IOException e) {
Log.e(TAG, "ConnectedThread: disconnected", e);
break;
}
}
}
/**
* Write to the connected OutStream.
*
* @param buffer
* The bytes to write
*/
public void write(byte[] buffer) {
try {
mmOutStream.write(buffer);
// Share the sent message back to the UI Activity
mHandler.obtainMessage(MESSAGE_WRITE, -1, -1, buffer).sendToTarget();
// mmOutStream.flush();
} catch (IOException e) {
Log.e(TAG, "Exception during write", e);
connectionFailed();
}
}
public void cancel() {
if(D)
Log.i(TAG, "connected Thread cancel");
resetConnection(mmSocket);
}
}
And I receive this error:
DEBUG/BluetoothConnectionService(3439): create ConnectedThread
INFO/BluetoothConnectionService(3439): Get input stream
INFO/BluetoothConnectionService(3439): Get output stream
INFO/BluetoothConnectionService(3439): isConnected = true
INFO/BluetoothConnectionService(3439): BEGIN mConnectedThread
INFO/BluetoothConnectionService(3439): start read mmInStream
INFO/BluetoothConnectionService(3439): setState() 2 -> 3
INFO/ProtectionService(3439): MESSAGE_STATE_CHANGE: 3
DEBUG/ProtectionService(3439): connectionEstablished
**ERROR/BluetoothConnectionService(3439): ConnectedThread : disconnected
ERROR/BluetoothConnectionService(3439): java.io.IOException: Software caused connection abort
ERROR/BluetoothConnectionService(3439): at android.bluetooth.BluetoothSocket.readNative(Native Method)
ERROR/BluetoothConnectionService(3439): at android.bluetooth.BluetoothSocket.read(BluetoothSocket.java:307)
ERROR/BluetoothConnectionService(3439): at android.bluetooth.BluetoothInputStream.read(BluetoothInputStream.java:96)
ERROR/BluetoothConnectionService(3439): at java.io.InputStream.read(InputStream.java:133)**
INFO/ProtectionService(3439): Send Bluetooth message
**ERROR/BluetoothConnectionService(3439): Exception during write
ERROR/BluetoothConnectionService(3439): java.io.IOException: Transport endpoint is not connected
ERROR/BluetoothConnectionService(3439): at android.bluetooth.BluetoothSocket.writeNative(Native Method)
ERROR/BluetoothConnectionService(3439): at android.bluetooth.BluetoothSocket.write(BluetoothSocket.java:317)**
The error clearly come when I am doing this:
bytes = mmInStream.read(buffer);
What am I doing wrong?
I had a very similar problem some days ago…
Try adding this check to your code:
This fixed my problem…
Good Luck 😉