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Why this Exception occurs 'o.StreamCorruptedException: invalid stream header: D8322EDA'

I'm working with Bluetooth in android.My main goal is to transmit large video file via Bluetooth.
I'm following Bluetooth chat sample for connectivity.
Actually i convert video into byte array and then in onRecieve method convert back to File.
when converting back to file some exception occurs.
I increased the buffer size in connected Thread.
To convert recieved byte[] into Hashmap<String, Byte[]>
private Object convertFromBytes(byte[] bytes) {
ByteArrayInputStream bis = new ByteArrayInputStream(bytes);
Object out = null;
ObjectInput in = null;
try {
in = new ObjectInputStream(bis);
out = in.readObject();
Log.d("bytetodata out", "");
} catch (IOException | ClassNotFoundException e) {
e.printStackTrace();
Log.d("bytetodata out", e.getLocalizedMessage());
} finally {
try {
if (in != null) {
in.close();
}
} catch (IOException ex) {
Log.e(TAG, ex.getLocalizedMessage());
// ignore close exception
}
}
Log.d("bytetodata out", "");
return out;
}
Exception occurs at
in = new ObjectInputStream(bis);
Bluetooth Reciever code
case MESSAGE_READ:
byte[] readBuf = (byte[]) msg.obj;
// construct a string from the valid bytes in the buffer
onRecieve(readBuf);
private void onRecieve(byte[] readBuf) {
HashMap<String, byte[]> receivedMap = (HashMap<String, byte[]>) convertFromBytes(readBuf);
//Log.d("recieveMAP Size" , String.valueOf(receivedMap.size()));
if (receivedMap != null && receivedMap.size() == 2) {
byte[] filebyte = receivedMap.get("file");
byte[] objectbyte = receivedMap.get("object");
if (filebyte != null) {
File file = new File("storage/emulated/0/Download/name.mp4");
try {
file.createNewFile();
} catch (IOException e) {
e.printStackTrace();
Log.e("Mainactivity", e.getLocalizedMessage());
}
if (file.exists()) {
try {
FileUtils.writeByteArrayToFile(file, filebyte);
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, e.getLocalizedMessage());
}
} else {
//System.out.println("file created: " + file);
Toast.makeText(context, "File is Empty", Toast.LENGTH_LONG).show();
}
} else {
Log.e(TAG, "selected video path = null!");
}
//System.out.println("file created: " + file);
//Toast.makeText(context, "File Created", Toast.LENGTH_LONG).show();
// Video video = (Video) convertFromBytes(objectbyte);
}
}
Bluetooth Connectivity code
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the BluetoothSocket input and output streams
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[ 4096 * 16 ];
int bytes;
// Keep listening to the InputStream while connected
while (true) {
try {
// Read from the InputStream
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(BTListFragment.MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
connectionLost();
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(BTListFragment.MESSAGE_WRITE, -1, -1, buffer)
.sendToTarget();
} catch (IOException e) {
}
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
}
}
}
BlutoothConnectivityService.java
package com.example.accessagriculture.Utils;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import com.example.accessagriculture.Views.Fragments.BTListFragment;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.UUID;
/**
* This class does all the work for setting up and managing Bluetooth
* connections with other devices. It has a thread that listens for
* incoming connections, a thread for connecting with a device, and a
* thread for performing data transmissions when connected.
*/
public class BTConnectService {
// Name for the SDP record when creating server socket
private static final String NAME = "BluetoothChat";
// Unique UUID for this application
private static final UUID MY_UUID = UUID.fromString("fa87c0d0-afac-11de-8a39-0800200c9a66");
// Member fields
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private AcceptThread mAcceptThread;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private int mState;
// Constants that indicate the current connection state
public static final int STATE_NONE = 0; // we're doing nothing
public static final int STATE_LISTEN = 1; // now listening for incoming connections
public static final int STATE_CONNECTING = 2; // now initiating an outgoing connection
public static final int STATE_CONNECTED = 3; // now connected to a remote device
/**
* Constructor. Prepares a new BluetoothChat session.
* #param handler A Handler to send messages back to the UI Activity
*/
public BTConnectService(Handler handler) {
mAdapter = BluetoothAdapter.getDefaultAdapter();
mState = STATE_NONE;
mHandler = handler;
}
/**
* Set the current state of the chat connection
*
* #param state An integer defining the current connection state
*/
private synchronized void setState(int state) {
mState = state;
// Give the new state to the Handler so the UI Activity can update
mHandler.obtainMessage(BTListFragment.MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
}
/**
* Return the current connection state.
*/
public synchronized int getState() {
return mState;
}
/**
* Start the chat service. Specifically start AcceptThread to begin a
* session in listening (server) mode. Called by the Activity onResume()
*/
public synchronized void start() {
// Cancel any thread attempting to make a connection
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
// Start the thread to listen on a BluetoothServerSocket
if (mAcceptThread == null) {
mAcceptThread = new AcceptThread();
mAcceptThread.start();
}
setState(STATE_LISTEN);
}
/**
* Start the ConnectThread to initiate a connection to a remote device.
*
* #param device The BluetoothDevice to connect
*/
public synchronized void connect(BluetoothDevice device) {
// Cancel any thread attempting to make a connection
if (mState == STATE_CONNECTING) {
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
// Start the thread to connect with the given device
mConnectThread = new ConnectThread(device);
mConnectThread.start();
setState(STATE_CONNECTING);
}
/**
* Start the ConnectedThread to begin managing a Bluetooth connection
*
* #param socket The BluetoothSocket on which the connection was made
* #param device The BluetoothDevice that has been connected
*/
public synchronized void connected(BluetoothSocket socket, BluetoothDevice device) {
// Cancel the thread that completed the connection
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
// Cancel the accept thread because we only want to connect to one device
if (mAcceptThread != null) {
mAcceptThread.cancel();
mAcceptThread = null;
}
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(socket);
mConnectedThread.start();
// Send the name of the connected device back to the UI Activity
Message msg = mHandler.obtainMessage(BTListFragment.MESSAGE_DEVICE_NAME);
Bundle bundle = new Bundle();
bundle.putString(BTListFragment.DEVICE_NAME, device.getName());
msg.setData(bundle);
mHandler.sendMessage(msg);
setState(STATE_CONNECTED);
}
/**
* Stop all threads
*/
public synchronized void stop() {
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
if (mAcceptThread != null) {
mAcceptThread.cancel();
mAcceptThread = null;
}
setState(STATE_NONE);
}
/**
* Write to the ConnectedThread in an unsynchronized manner
*
* #param out The bytes to write
* #see ConnectedThread#write(byte[])
*/
public void write(byte[] out) {
// Create temporary object
ConnectedThread r;
// Synchronize a copy of the ConnectedThread
synchronized (this) {
if (mState != STATE_CONNECTED) return;
r = mConnectedThread;
}
// Perform the write unsynchronized
r.write(out);
}
/**
* Indicate that the connection attempt failed and notify the UI Activity.
*/
private void connectionFailed() {
setState(STATE_LISTEN);
// Send a failure message back to the Activity
Message msg = mHandler.obtainMessage(BTListFragment.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(BTListFragment.TOAST, "Unable to connect device");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* Indicate that the connection was lost and notify the UI Activity.
*/
private void connectionLost() {
//setState(STATE_LISTEN);
// Send a failure message back to the Activity
/*Message msg = mHandler.obtainMessage(BTListFragment.MESSAGE_TOAST);
//Bundle bundle = new Bundle();
// bundle.putString(BTListFragment.TOAST, "Device connection was lost");
msg.setData(bundle);
mHandler.sendMessage(msg);*/
}
/**
* This thread runs while listening for incoming connections. It behaves
* like a server-side client. It runs until a connection is accepted
* (or until cancelled).
*/
private class AcceptThread extends Thread {
// The local server socket
private final BluetoothServerSocket mmServerSocket;
public AcceptThread() {
BluetoothServerSocket tmp = null;
// Create a new listening server socket
try {
tmp = mAdapter.listenUsingRfcommWithServiceRecord(NAME, MY_UUID);
} catch (IOException e) {
}
mmServerSocket = tmp;
}
public void run() {
setName("AcceptThread");
BluetoothSocket socket = null;
// Listen to the server socket if we're not connected
while (mState != STATE_CONNECTED) {
try {
// This is a blocking call and will only return on a
// successful connection or an exception
socket = mmServerSocket.accept();
} catch (IOException e) {
break;
}
// If a connection was accepted
if (socket != null) {
synchronized (BTConnectService.this) {
switch (mState) {
case STATE_LISTEN:
case STATE_CONNECTING:
// Situation normal. Start the connected thread.
connected(socket, socket.getRemoteDevice());
break;
case STATE_NONE:
case STATE_CONNECTED:
// Either not ready or already connected. Terminate new socket.
try {
socket.close();
} catch (IOException e) {
}
break;
}
}
}
}
}
public void cancel() {
try {
mmServerSocket.close();
} catch (IOException e) {
}
}
}
/**
* This thread runs while attempting to make an outgoing connection
* with a device. It runs straight through; the connection either
* succeeds or fails.
*/
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
BluetoothSocket tmp = null;
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
tmp = device.createRfcommSocketToServiceRecord(MY_UUID);
} catch (IOException e) {
}
mmSocket = tmp;
}
public void run() {
setName("ConnectThread");
// Always cancel discovery because it will slow down a connection
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
mmSocket.connect();
} catch (IOException e) {
connectionFailed();
// Close the socket
try {
mmSocket.close();
} catch (IOException e2) {
}
// Start the service over to restart listening mode
BTConnectService.this.start();
return;
}
// Reset the ConnectThread because we're done
synchronized (BTConnectService.this) {
mConnectThread = null;
}
// Start the connected thread
connected(mmSocket, mmDevice);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
}
}
}
/**
* This thread runs during a connection with a remote device.
* It handles all incoming and outgoing transmissions.
*/
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the BluetoothSocket input and output streams
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
byte[] buffer = new byte[1024];
int bytes;
// Keep listening to the InputStream while connected
while (true) {
try {
// Read from the InputStream
bytes = mmInStream.read(buffer);
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(BTListFragment.MESSAGE_READ, bytes, -1, buffer)
.sendToTarget();
} catch (IOException e) {
connectionLost();
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(BTListFragment.MESSAGE_WRITE, -1, -1, buffer)
.sendToTarget();
} catch (IOException e) {
}
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
}
}
}
}

The coding frame with ObjectOutputStream. On the sender site
HashMap<String, Object> hm = new HashMap<>();
...
ByteArrayOutputStream bao = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(bao);
oos.writeObject(hm);
Socket.getOutputStream().write(bao.toByteArray()); // send the
...
on the receiver site
private Object convertFromBytes(byte[] bytes) {
... // your codes
}
I'm sorry. I missed to read that you send the bytes in chunks. But, normally the sending takes over the sending package (chunked or not) and the receiving task is responsible for the assembling the chunks. Since you work explicitly with ChunkOutputStream and ChunkInputStream

Error writing to output stream. socket closed

I have a 2 fragment and i have to call bluetooth connection class in the both of them. 1.st fragment connected devices and second i try to send message but i cant because this error.
This error very tired to me because i can not find any solutions.What is the reason of the this problem. Please help me how can i fix it ?
D/BluetoothConnectionServ2: write: Write Called.
write: Writing to outputstream: g yh6gg6
E/BluetoothConnectionServ2: write: Error writing to output stream. socket closed
That because of the :
(But i can not solve now)
(I am waiting your help)
I have to connect device on the other Fragment. Because my Connection not live. So if i call the this line again on the fragment:
mBluetoothService.startClient(device,MY_UUID_INSECURE);
So if i called this way. Mybluetooth Connection class close other connection and close socket so i have a error. So i have to keep connection.
But now how can i find solution ?
BluetoothConnection Service:
public class BluetoothConnectionService2 {
private static final String TAG = "BluetoothConnectionServ";
private static final String appName = "MYAPP";
private static final UUID MY_UUID_INSECURE =
UUID.fromString("90fe5f0d-823c-4215-b5ff-e96ad59d62cc");
private final BluetoothAdapter mBluetoothAdapter;
Context mContext;
private AcceptThread mInsecureAcceptThread;
private ConnectThread mConnectThread;
private BluetoothDevice mmDevice;
private UUID deviceUUID;
ProgressDialog mProgressDialog;
private ConnectedThread mConnectedThread;
public BluetoothConnectionService2(Context context) {
mContext = context;
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
start();
}
/**
* This thread runs while listening for incoming connections. It behaves
* like a server-side client. It runs until a connection is accepted
* (or until cancelled).
*/
private class AcceptThread extends Thread {
// The local server socket
private final BluetoothServerSocket mmServerSocket;
public AcceptThread(){
BluetoothServerSocket tmp = null;
// Create a new listening server socket
try{
tmp = mBluetoothAdapter.listenUsingInsecureRfcommWithServiceRecord(appName,MY_UUID_INSECURE);
Log.d(TAG, "AcceptThread: Setting up Server using: " + MY_UUID_INSECURE);
}catch (IOException e){
Log.e(TAG, "AcceptThread: IOException: " + e.getMessage() );
}
mmServerSocket = tmp;
}
public void run(){
Log.d(TAG, "run: AcceptThread Running.");
BluetoothSocket socket = null;
try{
// This is a blocking call and will only return on a
// successful connection or an exception
Log.d(TAG, "run: RFCOM server socket start.....");
socket = mmServerSocket.accept();
Log.d(TAG, "run: RFCOM server socket accepted connection.");
}catch (IOException e){
Log.e(TAG, "AcceptThread: IOException: " + e.getMessage() );
}
//talk about this is in the 3rd
if(socket != null){
connected(socket,mmDevice);
}
Log.i(TAG, "END mAcceptThread ");
}
public void cancel() {
Log.d(TAG, "cancel: Canceling AcceptThread.");
try {
mmServerSocket.close();
} catch (IOException e) {
Log.e(TAG, "cancel: Close of AcceptThread ServerSocket failed. " + e.getMessage() );
}
}
}
/**
* This thread runs while attempting to make an outgoing connection
* with a device. It runs straight through; the connection either
* succeeds or fails.
*/
private class ConnectThread extends Thread {
private BluetoothSocket mmSocket;
public ConnectThread(BluetoothDevice device, UUID uuid) {
Log.d(TAG, "ConnectThread: started.");
mmDevice = device;
deviceUUID = uuid;
}
public void run(){
mBluetoothAdapter.cancelDiscovery();
BluetoothSocket tmp = null;
Log.i(TAG, "RUN mConnectThread ");
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
Log.d(TAG, "ConnectThread: Trying to create InsecureRfcommSocket using UUID: "
+MY_UUID_INSECURE );
tmp = mmDevice.createRfcommSocketToServiceRecord(deviceUUID);
} catch (IOException e) {
Log.e(TAG, "ConnectThread: Could not create InsecureRfcommSocket " + e.getMessage());
}
mmSocket = tmp;
// Always cancel discovery because it will slow down a connection
mBluetoothAdapter.cancelDiscovery();
// Make a connection to the BluetoothSocket
try {
mmSocket.connect();
Thread.sleep(3000);
Log.d(TAG, "run: ConnectThread connected.");
} catch (IOException e) {
// Close the socket
try {
mmSocket.close();
} catch (IOException e1) {
e1.printStackTrace();
}
Log.d(TAG, "run: ConnectThread: Could not connect to UUID: " + MY_UUID_INSECURE );
} catch (InterruptedException e) {
e.printStackTrace();
}
connected(mmSocket,mmDevice);
}
public void cancel() {
try {
Log.d(TAG, "cancel: Closing Client Socket.");
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "cancel: close() of mmSocket in Connectthread failed. " + e.getMessage());
}
}
}
/**
* Start the chat service. Specifically start AcceptThread to begin a
* session in listening (server) mode. Called by the Activity onResume()
*/
public synchronized void start() {
Log.d(TAG, "start");
// Cancel any thread attempting to make a connection
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
if (mInsecureAcceptThread == null) {
mInsecureAcceptThread = new AcceptThread();
mInsecureAcceptThread.start();
}
}
/**
AcceptThread starts and sits waiting for a connection.
Then ConnectThread starts and attempts to make a connection with the other devices AcceptThread.
**/
public synchronized void startClient(BluetoothDevice device,UUID uuid){
Log.d(TAG, "startClient: Started.");
//initprogress dialog
mProgressDialog = ProgressDialog.show(mContext,"Connecting Bluetooth"
,"Please Wait...",true);
mConnectThread = new ConnectThread(device, uuid);
mConnectThread.start();
}
/**
Finally the ConnectedThread which is responsible for maintaining the BTConnection, Sending the data, and
receiving incoming data through input/output streams respectively.
**/
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
Log.d(TAG, "ConnectedThread: Starting.");
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
//dismiss the progressdialog when connection is established
try{
mProgressDialog.dismiss();
}catch (NullPointerException e){
e.printStackTrace();
}
try {
tmpIn = mmSocket.getInputStream();
tmpOut = mmSocket.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run(){
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
}
//Call this from the main activity to send data to the remote device
public void write(byte[] bytes) {
String text = new String(bytes, Charset.defaultCharset());
Log.d(TAG, "write: Writing to outputstream: " + text);
try {
mmOutStream.write(bytes);
Thread.sleep(3000);
mmOutStream.flush();
} catch (IOException e) {
Log.e(TAG, "write: Error writing to output stream. " + e.getMessage() );
} catch (InterruptedException e) {
e.printStackTrace();
}
}
/* Call this from the main activity to shutdown the connection */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
private void connected(BluetoothSocket mmSocket, BluetoothDevice mmDevice) {
Log.d(TAG, "connected: Starting.");
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(mmSocket);
mConnectedThread.start();
}
/**
* Write to the ConnectedThread in an unsynchronized manner
*
* #param out The bytes to write
* #see ConnectedThread#write(byte[])
*/
public void write(byte[] out) {
// Create temporary object
ConnectedThread r;
if(mConnectedThread==null){
}
// Synchronize a copy of the ConnectedThread
Log.d(TAG, "write: Write Called.");
//perform the write
mConnectedThread.write(out);
}
}

You should keep live your connection this is true.But if fragments will close same time connection will stop.You should not close first fragment maybe you can make invisible first fragment.

Bluetooth write function does not work

I have a Stringbuffer that keeps asci to hex value. (Not empty) and than i want to send with bluetooth. But i have a null object erorr but does not null.
(I am working on the fragment that is include bluetoothservice.java)
BluetoothConnectionService mBluetoothConnection;
...
for (char c: ch) {
int i= (int) c;
sbuffer.append(Integer.toHexString(i).toUpperCase());
text.setText(sbuffer);
}
....
If i press the send button, my hex sstringbuffer has to send bluetooth but doesnt work correctly.
send.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(sbuffer!=null) {
byte[] bytes = sbuffer.toString().getBytes(Charset.defaultCharset());
mBluetoothConnection.write(bytes);
}
}
});
Bluetoothconnection.java
package com.example.duygu.mybluetoothdevicelist;
import android.app.ProgressDialog;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothServerSocket;
import android.bluetooth.BluetoothSocket;
import android.content.Context;
import android.content.Intent;
import android.support.v4.content.LocalBroadcastManager;
import android.util.Log;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.charset.Charset;
import java.util.UUID;
public class BluetoothConnectionService {
private static final String TAG = "BluetoothConnectionServ";
private static final String appName = "MYAPP";
private static final UUID MY_UUID_INSECURE =
UUID.fromString("8ce255c0-200a-11e0-ac64-0800200c9a66");
private final BluetoothAdapter mBluetoothAdapter;
Context mContext;
private AcceptThread mInsecureAcceptThread;
private ConnectThread mConnectThread;
private BluetoothDevice mmDevice;
private UUID deviceUUID;
ProgressDialog mProgressDialog;
private ConnectedThread mConnectedThread;
public BluetoothConnectionService(Context context) {
mContext = context;
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
start();
}
/**
* This thread runs while listening for incoming connections. It behaves
* like a server-side client. It runs until a connection is accepted
* (or until cancelled).
*/
private class AcceptThread extends Thread {
// The local server socket
private final BluetoothServerSocket mmServerSocket;
public AcceptThread(){
BluetoothServerSocket tmp = null;
// Create a new listening server socket
try{
tmp = mBluetoothAdapter.listenUsingInsecureRfcommWithServiceRecord(appName, MY_UUID_INSECURE);
Log.d(TAG, "AcceptThread: Setting up Server using: " + MY_UUID_INSECURE);
}catch (IOException e){
Log.e(TAG, "AcceptThread: IOException: " + e.getMessage() );
}
mmServerSocket = tmp;
}
public void run(){
Log.d(TAG, "run: AcceptThread Running.");
BluetoothSocket socket = null;
try{
// This is a blocking call and will only return on a
// successful connection or an exception
Log.d(TAG, "run: RFCOM server socket start.....");
socket = mmServerSocket.accept();
Log.d(TAG, "run: RFCOM server socket accepted connection.");
}catch (IOException e){
Log.e(TAG, "AcceptThread: IOException: " + e.getMessage() );
}
//talk about this is in the 3rd
if(socket != null){
connected(socket,mmDevice);
}
Log.i(TAG, "END mAcceptThread ");
}
public void cancel() {
Log.d(TAG, "cancel: Canceling AcceptThread.");
try {
mmServerSocket.close();
} catch (IOException e) {
Log.e(TAG, "cancel: Close of AcceptThread ServerSocket failed. " + e.getMessage() );
}
}
}
/**
* This thread runs while attempting to make an outgoing connection
* with a device. It runs straight through; the connection either
* succeeds or fails.
*/
private class ConnectThread extends Thread {
private BluetoothSocket mmSocket;
public ConnectThread(BluetoothDevice device, UUID uuid) {
Log.d(TAG, "ConnectThread: started.");
mmDevice = device;
deviceUUID = uuid;
}
public void run(){
BluetoothSocket tmp = null;
Log.i(TAG, "RUN mConnectThread ");
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
Log.d(TAG, "ConnectThread: Trying to create InsecureRfcommSocket using UUID: "
+MY_UUID_INSECURE );
tmp = mmDevice.createRfcommSocketToServiceRecord(deviceUUID);
} catch (IOException e) {
Log.e(TAG, "ConnectThread: Could not create InsecureRfcommSocket " + e.getMessage());
}
mmSocket = tmp;
// Always cancel discovery because it will slow down a connection
mBluetoothAdapter.cancelDiscovery();
// Make a connection to the BluetoothSocket
try {
// This is a blocking call and will only return on a
// successful connection or an exception
mmSocket.connect();
Log.d(TAG, "run: ConnectThread connected.");
} catch (IOException e) {
// Close the socket
try {
mmSocket.close();
Log.d(TAG, "run: Closed Socket.");
} catch (IOException e1) {
Log.e(TAG, "mConnectThread: run: Unable to close connection in socket " + e1.getMessage());
}
Log.d(TAG, "run: ConnectThread: Could not connect to UUID: " + MY_UUID_INSECURE );
}
//will talk about this in the 3rd video
connected(mmSocket,mmDevice);
}
public void cancel() {
try {
Log.d(TAG, "cancel: Closing Client Socket.");
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "cancel: close() of mmSocket in Connectthread failed. " + e.getMessage());
}
}
}
/**
* Start the chat service. Specifically start AcceptThread to begin a
* session in listening (server) mode. Called by the Activity onResume()
*/
public synchronized void start() {
Log.d(TAG, "start");
// Cancel any thread attempting to make a connection
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
if (mInsecureAcceptThread == null) {
mInsecureAcceptThread = new AcceptThread();
mInsecureAcceptThread.start();
}
}
/**
AcceptThread starts and sits waiting for a connection.
Then ConnectThread starts and attempts to make a connection with the other devices AcceptThread.
**/
public void startClient(BluetoothDevice device,UUID uuid){
Log.d(TAG, "startClient: Started.");
//initprogress dialog
mProgressDialog = ProgressDialog.show(mContext,"Connecting Bluetooth"
,"Please Wait...",true);
mConnectThread = new ConnectThread(device, uuid);
mConnectThread.start();
}
/**
Finally the ConnectedThread which is responsible for maintaining the BTConnection, Sending the data, and
receiving incoming data through input/output streams respectively.
**/
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
Log.d(TAG, "ConnectedThread: Starting.");
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
//dismiss the progressdialog when connection is established
try{
mProgressDialog.dismiss();
}catch (NullPointerException e){
e.printStackTrace();
}
try {
tmpIn = mmSocket.getInputStream();
tmpOut = mmSocket.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run(){
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) {
// Read from the InputStream
try {
bytes = mmInStream.read(buffer);
String incomingMessage = new String(buffer, 0, bytes);
Log.d(TAG, "InputStream: " + incomingMessage);
Intent incomingMessageIntent = new Intent("incomingMessage");
incomingMessageIntent.putExtra("theMessage", incomingMessage);
LocalBroadcastManager.getInstance(mContext).sendBroadcast(incomingMessageIntent);
} catch (IOException e) {
Log.e(TAG, "write: Error reading Input Stream. " + e.getMessage() );
break;
}
}
}
//Call this from the main activity to send data to the remote device
public void write(byte[] bytes) {
String text = new String(bytes, Charset.defaultCharset());
Log.d(TAG, "write: Writing to outputstream: " + text);
try {
mmOutStream.write(bytes);
} catch (IOException e) {
Log.e(TAG, "write: Error writing to output stream. " + e.getMessage() );
}
}
/* Call this from the main activity to shutdown the connection */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
private void connected(BluetoothSocket mmSocket, BluetoothDevice mmDevice) {
Log.d(TAG, "connected: Starting.");
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(mmSocket);
mConnectedThread.start();
}
/**
* Write to the ConnectedThread in an unsynchronized manner
*
* #param out The bytes to write
* #see ConnectedThread#write(byte[])
*/
public void write(byte[] out) {
// Create temporary object
ConnectedThread r;
// Synchronize a copy of the ConnectedThread
Log.d(TAG, "write: Write Called.");
//perform the write
mConnectedThread.write(out);
}
}
This is my log.cat:
java.lang.NullPointerException: Attempt to invoke virtual method 'void com.example.duygu.mybluetoothdevicelist.BluetoothConnectionService.write(byte[])' on a null object reference
at com.example.duygu.mybluetoothdevicelist.OTA_Update$1.onClick(OTA_Update.java:82)
at android.view.View.performClick(View.java:5201)
at android.view.View$PerformClick.run(View.java:21215)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5525)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:730)
EDIT 1 on the send message fragment but does not work again. I cant connect with the bluetoothservice.java
public class OTA_Update extends Fragment {
BluetoothConnectionService mBluetoothConnection;
BluetoothAdapter mBluetoothAdapter;
private View convertView;
String data;
StringBuffer sbuffer= new StringBuffer();
TextView text;
int read;
int data_set;
Button send;
BluetoothDevice mBTDevice;
private static final UUID MY_UUID_INSECURE =
UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if(convertView==null) {
convertView = inflater.inflate(R.layout.fragment_ota__update, container, false);
text=(TextView)convertView.findViewById(R.id.text);
InputStream is =this.getResources().openRawResource(R.raw.blink);
BufferedReader reader = new BufferedReader( new InputStreamReader(is));
send =(Button) convertView.findViewById(R.id.send);
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
mBluetoothConnection = new BluetoothConnectionService(getActivity().getApplicationContext());
if(is!=null){
try {
while ((data = reader.readLine()) != null) {
char [] ch =data.toCharArray();
for (char c: ch) {
int i= (int) c;
sbuffer.append(Integer.toHexString(i).toUpperCase());
text.setText(sbuffer);
}
}
is.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
send.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if(sbuffer!=null) {
byte[] bytes = sbuffer.toString().getBytes(Charset.defaultCharset());
mBluetoothConnection.write(bytes);
}
}
});
}
return convertView;
// Inflate the layout for this fragment
}
}

You need to instantiate mBluetoothConnection, as it is null it raise the NullPointerException. Give more code to see where you declare/initialize (or not) the variable mBluetoothConnection.

Android Bluetooth method call

My Application contains 3 Activities -
MainActivity.java
Write.java
BluetoothConnectionService.java
BluetoothConnectionService.java
public class BluetoothConnectionService {
private static final String TAG = "BluetoothConnectionServ";
private static final String appName = "MYAPP";
private static final UUID MY_UUID_INSECURE =
UUID.fromString("8ce255c0-200a-11e0-ac64-0800200c9a66");
private final BluetoothAdapter mBluetoothAdapter;
Context mContext;
private AcceptThread mInsecureAcceptThread;
private ConnectThread mConnectThread;
private BluetoothDevice mmDevice;
private UUID deviceUUID;
ProgressDialog mProgressDialog;
private ConnectedThread mConnectedThread;
public BluetoothConnectionService(Context context) {
mContext = context;
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
//start();
}
/**
* This thread runs while listening for incoming connections. It behaves
* like a server-side client. It runs until a connection is accepted
* (or until cancelled).
*/
private class AcceptThread extends Thread {
// The local server socket
private final BluetoothServerSocket mmServerSocket;
public AcceptThread(){
BluetoothServerSocket tmp = null;
// Create a new listening server socket
try{
tmp = mBluetoothAdapter.listenUsingInsecureRfcommWithServiceRecord(appName, MY_UUID_INSECURE);
Log.d(TAG, "AcceptThread: Setting up Server using: " + MY_UUID_INSECURE);
}catch (IOException e){
Log.e(TAG, "AcceptThread: IOException: " + e.getMessage() );
}
mmServerSocket = tmp;
}
public void run(){
Log.d(TAG, "run: AcceptThread Running.");
BluetoothSocket socket = null;
try{
// This is a blocking call and will only return on a
// successful connection or an exception
Log.d(TAG, "run: RFCOM server socket start.....");
socket = mmServerSocket.accept();
Log.d(TAG, "run: RFCOM server socket accepted connection.");
}catch (IOException e){
Log.e(TAG, "AcceptThread: IOException: " + e.getMessage() );
}
if(socket != null){
connected(socket,mmDevice);
}
Log.i(TAG, "END mAcceptThread ");
}
public void cancel() {
Log.d(TAG, "cancel: Canceling AcceptThread.");
try {
mmServerSocket.close();
} catch (IOException e) {
Log.e(TAG, "cancel: Close of AcceptThread ServerSocket failed. " + e.getMessage() );
}
}
}
/**
* This thread runs while attempting to make an outgoing connection
* with a device. It runs straight through; the connection either
* succeeds or fails.
*/
private class ConnectThread extends Thread {
private BluetoothSocket mmSocket;
public ConnectThread(BluetoothDevice device, UUID uuid) {
Log.d(TAG, "ConnectThread: started.");
mmDevice = device;
deviceUUID = uuid;
}
public void run(){
BluetoothSocket tmp = null;
Log.i(TAG, "RUN mConnectThread ");
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
Log.d(TAG, "ConnectThread: Trying to create InsecureRfcommSocket using UUID: "
+MY_UUID_INSECURE );
tmp = mmDevice.createRfcommSocketToServiceRecord(deviceUUID);
} catch (IOException e) {
Log.e(TAG, "ConnectThread: Could not create InsecureRfcommSocket " + e.getMessage());
}
mmSocket = tmp;
// Always cancel discovery because it will slow down a connection
mBluetoothAdapter.cancelDiscovery();
// Make a connection to the BluetoothSocket
try {
// This is a blocking call and will only return on a
// successful connection or an exception
mmSocket.connect();
Log.d(TAG, "run: ConnectThread connected.");
//mProgressDialog.cancel();
//Toast.makeText(mContext,"Connected", Toast.LENGTH_SHORT).show();
} catch (IOException e) {
// Close the socket
try {
mmSocket.close();
Log.d(TAG, "run: Closed Socket.");
} catch (IOException e1) {
Log.e(TAG, "mConnectThread: run: Unable to close connection in socket " + e1.getMessage());
}
Log.d(TAG, "run: ConnectThread: Could not connect to UUID: " + MY_UUID_INSECURE );
}
connected(mmSocket,mmDevice);
}
public void cancel() {
try {
Log.d(TAG, "cancel: Closing Client Socket.");
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "cancel: close() of mmSocket in Connectthread failed. " + e.getMessage());
}
}
}
private void connected(BluetoothSocket mmSocket, BluetoothDevice mmDevice) {
Log.d(TAG, "connected: Starting.");
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(mmSocket);
mConnectedThread.start();
//start new activity
Intent intent = new Intent(mContext, Write.class);
mContext.startActivity(intent);
}
/**
Finally the ConnectedThread which is responsible for maintaining the BTConnection, Sending the data, and
receiving incoming data through input/output streams respectively.
**/
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
Log.d(TAG, "ConnectedThread: Starting.");
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
//dismiss the progress dialog when connection is established
try{
mProgressDialog.dismiss();
}catch (NullPointerException e){
e.printStackTrace();
}
try {
tmpIn = mmSocket.getInputStream();
tmpOut = mmSocket.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run(){
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) {
// Read from the InputStream
try {
bytes = mmInStream.read(buffer);
String incomingMessage = new String(buffer, 0, bytes);
Log.d(TAG, "InputStream: " + incomingMessage);
Intent incomingMessageIntent = new Intent("incomingMessage");
incomingMessageIntent.putExtra("theMessage", incomingMessage);
LocalBroadcastManager.getInstance(mContext).sendBroadcast(incomingMessageIntent);
Log.d(TAG, "broadcast sent");
} catch (IOException e) {
Log.e(TAG, "write: Error reading Input Stream. " + e.getMessage() );
break;
}
}
}
//Call this from the main activity to send data to the remote device
/*public void write(byte[] bytes) {
String text = new String(bytes, Charset.defaultCharset());
Log.d(TAG, "write: Writing to outputstream: " + text);
try {
mmOutStream.write(bytes);
} catch (IOException e) {
Log.e(TAG, "write: Error writing to output stream. " + e.getMessage() );
}
}*/
public void write(String input) {
byte[] msgBuffer = input.getBytes(); //converts entered String into bytes
try {
mmOutStream.write(msgBuffer); //write bytes over BT connection via outstream
} catch (IOException e) {
//if you cannot write, close the application
Toast.makeText(mContext, "Connection Failure", Toast.LENGTH_LONG).show();
}
}
/* Call this from the main activity to shutdown the connection */
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) { }
}
}
public void start() {
Log.d(TAG, "start");
// Cancel any thread attempting to make a connection
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
if (mInsecureAcceptThread == null) {
mInsecureAcceptThread = new AcceptThread();
mInsecureAcceptThread.start();
}
}
public void startClient(BluetoothDevice device,UUID uuid){
Log.d(TAG, "startClient: Started.");
//init progress dialog
mProgressDialog = ProgressDialog.show(mContext,"Connecting Bluetooth"
,"Please Wait...",true);
mConnectThread = new ConnectThread(device, uuid);
mConnectThread.start();
}
/**
* Write to the ConnectedThread in an unsynchronized manner
*
*/
public void write() {
// Create temporary object
//ConnectedThread r;
// Synchronize a copy of the ConnectedThread
Log.d(TAG, "write: Write Called.");
//perform the write
mConnectedThread.write("1");
}
}
PROBLEM:-
From the MainActivity, I created a BluetoothConnectionService object
BluetoothConnectionService mBluetoothConnection = new BluetoothConnectionService(MainActivity.this);
Then, I called startClient(device,uuid) method on mBluetoothConnection object
mBluetoothConnection.startClient(device,uuid);
Now, after successful connection is made, I can send out data to other devices by calling write() from the MainActivity
mBluetoothConnection.write();
But I don't want to send out data from MainActivity instead I want to use Write activity to send data out. How can I do that?

The Code you are using is provided by google Bluetooth chat application and they write using this:
In your Activity
private void sendMessage(String message) {
// Check that we're actually connected before trying anything
if (bluetoothConnectionService.getState() != BluetoothConnectionService.STATE_CONNECTED) {
Toast.makeText(MainActivity.this, R.string.not_connected, Toast.LENGTH_SHORT).show();
return;
}
// Check that there's actually something to send
if (message.length() > 0) {
// Get the message bytes and tell the BluetoothConnectionService to write
byte[] send = message.getBytes();
bluetoothConnectionService.write(send);
// Reset out string buffer to zero and clear the edit text field
mOutStringBuffer.setLength(0);
}
}
In the service add these two methods
/**
* Write to the ConnectedThread in an unsynchronized manner
*
* #param out The bytes to write
* #see ConnectedThread#write(byte[])
*/
public void write(byte[] out) {
// Create temporary object
ConnectedThread r;
// Synchronize a copy of the ConnectedThread
synchronized (this) {
if (mState != STATE_CONNECTED) return;
r = mConnectedThread;
}
// Perform the write unsynchronized
r.write(out);
}
/**
* 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(Constants.MESSAGE_WRITE, -1, -1, buffer)
.sendToTarget();
} catch (IOException e) {
Log.e(TAG, "Exception during write", e);
}
}

Connection is not created (failed or aborted) exception thrown during Bluetooth connection in Android

I am working on a project which makes use of an android tablet(iball 3G 7271) that runs on 4.1.2 and is made of MTK processor AND an RN42 bluetooth (chip on a PCB).These two modules communicate with each other to transfer data among them via bluetooth.
I am facing issues.wherein at certain instances I repeatedly get exceptions stating 'Connection is not created (failed or aborted)'.I have found the instances as described below:
I copied the relevant code from the BlueTerm app(from playstore) and made a sample app to test BT connectivity.Blueterm is an app to test bluetooth connectivity between a device and RN42.
1) I Connected/disconnected the app to RN42,and found that it was working all the time.Proper connection and disconnection was happening.
2) I Simulated power failure(by switching off just the RN42 module),I then disconnected & reconnected the BT connection between app and RN42 & found that the tablet was getting re-connected with RN42 without much issue.
3) Link between re-installation of the app and BT connectivity to the RN42
Test case 1:Before re-installation, the app was disconnected from RN42 ; result- after re-installation BT reconnection to RN42 in the re installed app works fine.
Test case 2:Before re-installation the app was in connected state to RN42;result- after re-installation BT reconnection to RN42 doesnt happen.
I traced that the exception that comes for Test case 2 is :
W/System.err(4603): java.io.IOException: [JSR82] connect: Connection is not created (failed or aborted).
W/System.err(4603): at android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:395)
This was the exception I was getting again and again few days back.So now I kinda know when this exception can get thrown.
NOTE: For 'Test case2' ,here even un-installing and re-installing the app and then trying to connect app to RN42 doesnt work.We need to reboot the tablet to make the app connect to BT again.Moreover,I even tried connecting the real BlueTerm app(in test case 2),but it also did not get connected.So then I tried switching OFF and ON the tablet's BT.I observed that by switching off and then switching ON the BT and then trying to establish BT connection between tablet and RN42 was happening .But now, I was not getting any input signals from RN42 to tablet,but was able to just send data from tablet to RN42.
Tesing on Samsung S2/grand/nexus devices:
For the above Test case2,on these devices the app does get connected to BT after re-installation,even if it was/was not connected to RN42 via BT prior to re-installation.
Below is the code of my app and the log cat exception:
BlueTerm.java
#SuppressLint("HandlerLeak")
public class BlueTerm extends Activity {
BluetoothSocket Socket;
OutputStream DataOut;
InputStream DataIn;
// Intent request codes
private static final int REQUEST_CONNECT_DEVICE = 1;
private static final int REQUEST_ENABLE_BT = 2;
private static TextView mTitle;
// Name of the connected device
private String mConnectedDeviceName = null;
/**
* Set to true to add debugging code and logging.
*/
public static final boolean DEBUG = true;
/**
* Set to true to log each character received from the remote process to the
* android log, which makes it easier to debug some kinds of problems with
* emulating escape sequences and control codes.
*/
public static final boolean LOG_CHARACTERS_FLAG = DEBUG && false;
/**
* Set to true to log unknown escape sequences.
*/
public static final boolean LOG_UNKNOWN_ESCAPE_SEQUENCES = DEBUG && false;
/**
* The tag we use when logging, so that our messages can be distinguished
* from other messages in the log. Public because it's used by several
* classes.
*/
public static final String LOG_TAG = "BlueTerm";
// Message types sent from the BluetoothReadService Handler
public static final int MESSAGE_STATE_CHANGE = 1;
public static final int MESSAGE_READ = 2;
public static final int MESSAGE_WRITE = 3;
public static final int MESSAGE_DEVICE_NAME = 4;
public static final int MESSAGE_TOAST = 5;
// Key names received from the BluetoothChatService Handler
public static final String DEVICE_NAME = "device_name";
public static final String TOAST = "toast";
private BluetoothAdapter mBluetoothAdapter = null;
private static BluetoothSerialService mSerialService = null;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (DEBUG)
Log.e(LOG_TAG, "+++ ON CREATE +++");
setContentView(R.layout.main);
mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
mSerialService = new BluetoothSerialService(this, mHandlerBT);
Button buzzerOn = (Button) findViewById(R.id.button1);
buzzerOn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Log.v("BlueTerm","Buzzer button clicked");
//send("37".getBytes());
send(bigIntToByteArray(37));
}
});
Button buzzerOff = (Button) findViewById(R.id.button2);
buzzerOff.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Log.v("BlueTerm","Buzzer button clicked");
//send("37".getBytes());
send(bigIntToByteArray(30));
}
});
Button recon = (Button) findViewById(R.id.button3);
recon.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Log.v("BlueTerm","recon button clicked");
BluetoothAdapter iballAdapter = BluetoothAdapter.getDefaultAdapter();
BluetoothDevice RN42_Device = iballAdapter.getRemoteDevice("00:06:66:49:57:5F");
try {
Socket = RN42_Device.createRfcommSocketToServiceRecord(UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"));
DataOut = Socket.getOutputStream();
DataIn = Socket.getInputStream();
} catch (Exception e1) {
e1.printStackTrace();
}
if (DataIn != null) {
Log.d("AppFunctions","DataIn is not null,so making it NULL");
try {DataIn.close();} catch (Exception e) {}
DataIn = null;
}
Log.i("AppFunctions", "DataOut -" + DataOut);
if (DataOut != null) {
Log.d("AppFunctions","DataOut is not null,so making it NULL");
try {DataOut.close();} catch (Exception e) {}
DataOut = null;
}
Log.i("AppFunctions", "Socket -" + Socket);
if (Socket != null) {
Log.d("AppFunctions","Socket is not null,so making it NULL");
try {Socket.close();} catch (Exception e) {}
Socket = null;
}
try {
Socket = RN42_Device.createRfcommSocketToServiceRecord(UUID.fromString("00001101-0000-1000-8000-00805F9B34FB"));
Socket.connect();
} catch (Exception e) {
e.printStackTrace();
}
if (mSerialService != null)
mSerialService.stop();
mSerialService.start();
}
});
if (DEBUG)
Log.e(LOG_TAG, "+++ DONE IN ON CREATE +++");
}
#Override
public void onStart() {
super.onStart();
if (DEBUG)
Log.e(LOG_TAG, "++ ON START ++");
mEnablingBT = false;
}
#Override
public synchronized void onResume() {
super.onResume();
if (DEBUG) {
Log.e(LOG_TAG, "+ ON RESUME +");
}
if (mSerialService != null) {
Log.v("BlueTerm","mSerialService is NOT null");
// Only if the state is STATE_NONE, do we know that we haven't started already
if (mSerialService.getState() == BluetoothSerialService.STATE_NONE) {
// Start the Bluetooth chat services
Log.v("BlueTerm","starting BT chat service");
mSerialService.start();
}
}
}
}
#Override
public synchronized void onPause() {
super.onPause();
if (DEBUG)
Log.e(LOG_TAG, "- ON PAUSE -");
}
#Override
public void onStop() {
super.onStop();
if(DEBUG)
Log.e(LOG_TAG, "-- ON STOP --");
}
#Override
public void onDestroy() {
super.onDestroy();
if (DEBUG)
Log.e(LOG_TAG, "--- ON DESTROY ---");
if (mSerialService != null)
mSerialService.stop();
}
public int getConnectionState() {
return mSerialService.getState();
}
public void send(byte[] out) {
mSerialService.write( out );
}
// The Handler that gets information back from the BluetoothService
private final Handler mHandlerBT = new Handler() {
#Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MESSAGE_STATE_CHANGE:
if(DEBUG) Log.i(LOG_TAG, "MESSAGE_STATE_CHANGE: " + msg.arg1);
switch (msg.arg1) {
case BluetoothSerialService.STATE_CONNECTED:
break;
case BluetoothSerialService.STATE_CONNECTING:
break;
case BluetoothSerialService.STATE_LISTEN:
case BluetoothSerialService.STATE_NONE:
Log.d("BlueTerm","inside STATE_NONE in handler");
break;
}
break;
case MESSAGE_WRITE:
if (mLocalEcho) {
byte[] writeBuf = (byte[]) msg.obj;
}
break;
case MESSAGE_READ:
byte[] readBuf = (byte[]) msg.obj;
Log.d("incoming writebytes",""+readBuf.toString());
break;
case MESSAGE_DEVICE_NAME:
// save the connected device's name
mConnectedDeviceName = msg.getData().getString(DEVICE_NAME);
Toast.makeText(getApplicationContext(), "Connected to "
+ mConnectedDeviceName, Toast.LENGTH_SHORT).show();
break;
case MESSAGE_TOAST:
Toast.makeText(getApplicationContext(), msg.getData().getString(TOAST),
Toast.LENGTH_SHORT).show();
break;
}
}
};
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if(DEBUG) Log.d(LOG_TAG, "onActivityResult " + resultCode);
switch (requestCode) {
case REQUEST_CONNECT_DEVICE:
// When DeviceListActivity returns with a device to connect
if (resultCode == Activity.RESULT_OK) {
// Get the device MAC address
String address = "00:06:66:49:57:5F";
// Get the BLuetoothDevice object
BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
// Attempt to connect to the device
mSerialService.connect(device);
}
break;
case REQUEST_ENABLE_BT:
// When the request to enable Bluetooth returns
if (resultCode == Activity.RESULT_OK) {
Log.d(LOG_TAG, "BT not enabled");
}
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.option_menu, menu);
mMenuItemConnect = menu.getItem(0);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.connect:
if (getConnectionState() == BluetoothSerialService.STATE_NONE) {
String address = "00:06:66:49:57:5F";
// Get the BLuetoothDevice object
BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address);
Log.d("BlueTerm","device: " + device);
// Attempt to connect to the device
mSerialService.connect(device);
}
else
if (getConnectionState() == BluetoothSerialService.STATE_CONNECTED) {
mSerialService.stop();
mSerialService.start();
}
return true;
case R.id.preferences:
//doPreferences();
return true;
case R.id.menu_special_keys:
//doDocumentKeys();
return true;
}
return false;
}
private byte[] bigIntToByteArray( final int i ) {
BigInteger bigInt = BigInteger.valueOf(i);
return bigInt.toByteArray();
}
}
BluetoothService:
/**
* This class does all the work for setting up and managing Bluetooth
* connections with other devices. It has a thread that listens for
* incoming connections, a thread for connecting with a device, and a
* thread for performing data transmissions when connected.
*/
public class BluetoothSerialService {
// Debugging
private static final String TAG = "BluetoothReadService";
private static final boolean D = true;
private static final UUID SerialPortServiceClass_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB");
// Member fields
private final BluetoothAdapter mAdapter;
private final Handler mHandler;
private ConnectThread mConnectThread;
private ConnectedThread mConnectedThread;
private int mState;
// Constants that indicate the current connection state
public static final int STATE_NONE = 0; // we're doing nothing
public static final int STATE_LISTEN = 1; // now listening for incoming connections
public static final int STATE_CONNECTING = 2; // now initiating an outgoing connection
public static final int STATE_CONNECTED = 3; // now connected to a remote device
/**
* Constructor. Prepares a new BluetoothChat session.
* #param context The UI Activity Context
* #param handler A Handler to send messages back to the UI Activity
*/
public BluetoothSerialService(Context context, Handler handler) {
mAdapter = BluetoothAdapter.getDefaultAdapter();
mState = STATE_NONE;
mHandler = handler;
// mEmulatorView = emulatorView;
}
/**
* Set the current state of the chat connection
* #param state An integer defining the current connection state
*/
private synchronized void setState(int state) {
if (D) Log.d(TAG, "setState() " + mState + " -> " + state);
mState = state;
Log.d("BluetoothSerialService","state : " + state);
// Give the new state to the Handler so the UI Activity can update
mHandler.obtainMessage(BlueTerm.MESSAGE_STATE_CHANGE, state, -1).sendToTarget();
}
/**
* Return the current connection state. */
public synchronized int getState() {
return mState;
}
/**
* Start the chat service. Specifically start AcceptThread to begin a
* session in listening (server) mode. Called by the Activity onResume() */
public synchronized void start() {
if (D) Log.d(TAG, "start");
// Cancel any thread attempting to make a connection
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
setState(STATE_NONE);
}
/**
* Start the ConnectThread to initiate a connection to a remote device.
* #param device The BluetoothDevice to connect
*/
public synchronized void connect(BluetoothDevice device) {
if (D) Log.d(TAG, "connect to: " + device);
// Cancel any thread attempting to make a connection
if (mState == STATE_CONNECTING) {
if (mConnectThread != null) {mConnectThread.cancel(); mConnectThread = null;}
}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {mConnectedThread.cancel(); mConnectedThread = null;}
// Start the thread to connect with the given device
mConnectThread = new ConnectThread(device);
mConnectThread.start();
setState(STATE_CONNECTING);
}
/**
* Start the ConnectedThread to begin managing a Bluetooth connection
* #param socket The BluetoothSocket on which the connection was made
* #param device The BluetoothDevice that has been connected
*/
public synchronized void connected(BluetoothSocket socket, BluetoothDevice device) {
if (D) Log.d(TAG, "connected");
// Cancel the thread that completed the connection
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
// Cancel any thread currently running a connection
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
// Start the thread to manage the connection and perform transmissions
mConnectedThread = new ConnectedThread(socket);
mConnectedThread.start();
// Send the name of the connected device back to the UI Activity
Message msg = mHandler.obtainMessage(BlueTerm.MESSAGE_DEVICE_NAME);
Bundle bundle = new Bundle();
bundle.putString(BlueTerm.DEVICE_NAME, device.getName());
msg.setData(bundle);
mHandler.sendMessage(msg);
setState(STATE_CONNECTED);
}
/**
* Stop all threads
*/
public synchronized void stop() {
if (D) Log.d(TAG, "stop");
if (mConnectThread != null) {
mConnectThread.cancel();
mConnectThread = null;
}
if (mConnectedThread != null) {
mConnectedThread.cancel();
mConnectedThread = null;
}
setState(STATE_NONE);
}
/**
* Write to the ConnectedThread in an unsynchronized manner
* #param out The bytes to write
* #see ConnectedThread#write(byte[])
*/
public void write(byte[] out) {
Log.e("BluetoothSerialService","Inside write fn" + " :" + out.toString());
// Create temporary object
ConnectedThread r;
// Synchronize a copy of the ConnectedThread
synchronized (this) {
if (mState != STATE_CONNECTED) return;
r = mConnectedThread;
}
// Perform the write unsynchronized
r.write(out);
}
/**
* Indicate that the connection attempt failed and notify the UI Activity.
*/
private void connectionFailed() {
setState(STATE_NONE);
// Send a failure message back to the Activity
Message msg = mHandler.obtainMessage(BlueTerm.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(BlueTerm.TOAST, "Unable to connect device");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* Indicate that the connection was lost and notify the UI Activity.
*/
private void connectionLost() {
setState(STATE_NONE);
// Send a failure message back to the Activity
Message msg = mHandler.obtainMessage(BlueTerm.MESSAGE_TOAST);
Bundle bundle = new Bundle();
bundle.putString(BlueTerm.TOAST, "Device connection was lost");
msg.setData(bundle);
mHandler.sendMessage(msg);
}
/**
* This thread runs while attempting to make an outgoing connection
* with a device. It runs straight through; the connection either
* succeeds or fails.
*/
private class ConnectThread extends Thread {
private final BluetoothSocket mmSocket;
private final BluetoothDevice mmDevice;
public ConnectThread(BluetoothDevice device) {
mmDevice = device;
BluetoothSocket tmp = null;
// Get a BluetoothSocket for a connection with the
// given BluetoothDevice
try {
tmp = device.createRfcommSocketToServiceRecord(SerialPortServiceClass_UUID);
} catch (IOException e) {
Log.e(TAG, "create() failed", e);
}
mmSocket = tmp;
}
public void run() {
Log.e(TAG, "BEGIN mConnectThread");
setName("ConnectThread");
// Always cancel discovery because it will slow down a connection
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
mmSocket.connect();
} catch (IOException e) {
connectionFailed();
// Close the socket
try {
mmSocket.close();
} catch (IOException e2) {
Log.e(TAG, "unable to close() socket during connection failure", e2);
}
// Start the service over to restart listening mode
//BluetoothSerialService.this.start();
return;
}
// Reset the ConnectThread because we're done
synchronized (BluetoothSerialService.this) {
mConnectThread = null;
}
// Start the connected thread
connected(mmSocket, mmDevice);
}
public void cancel() {
try {
mmSocket.close();
} catch (IOException e) {
Log.e(TAG, "close() of connect socket failed", e);
}
}
}
/**
* This thread runs during a connection with a remote device.
* It handles all incoming and outgoing transmissions.
*/
private class ConnectedThread extends Thread {
private final BluetoothSocket mmSocket;
private final InputStream mmInStream;
private final OutputStream mmOutStream;
public ConnectedThread(BluetoothSocket socket) {
Log.e(TAG, "create ConnectedThread");
mmSocket = socket;
InputStream tmpIn = null;
OutputStream tmpOut = null;
// Get the BluetoothSocket input and output streams
try {
tmpIn = socket.getInputStream();
tmpOut = socket.getOutputStream();
} catch (IOException e) {
Log.e(TAG, "temp sockets not created", e);
}
mmInStream = tmpIn;
mmOutStream = tmpOut;
}
public void run() {
Log.e(TAG, "BEGIN mConnectedThread");
byte[] buffer = new byte[1024];
int bytes;
// Keep listening to the InputStream while connected
Log.e(TAG, "Entering while");
while (true) {
Log.e(TAG, "Inside while");
try {
// Read from the InputStream
bytes = 0;
Log.d("incoming bytes",""+bytes);
Log.e("BT","Inputstream :" + mmInStream);
//bytes = mmInStream.read(buffer);
bytes = mmInStream.read();
Log.d("incoming bytes",""+bytes);
//mEmulatorView.write(buffer, bytes);
// Send the obtained bytes to the UI Activity
mHandler.obtainMessage(BlueTerm.MESSAGE_READ, bytes, -1, buffer).sendToTarget();
String a = buffer.toString();
a = "";
} catch (Exception e) {
Log.e(TAG, "disconnected", e);
connectionLost();
break;
}
bytes = 0;
}
//Log.e(TAG, "Outside while");
}
/**
* Write to the connected OutStream.
* #param buffer The bytes to write
*/
public void write(byte[] buffer) {
try {
Log.d("writing to outStream byte :", buffer.toString());
mmOutStream.write(buffer);
// Share the sent message back to the UI Activity
//mHandler.obtainMessage(BlueTerm.MESSAGE_WRITE, buffer.length, -1, buffer).sendToTarget();
} catch (IOException e) {
Log.e(TAG, "Exception during write", e);
}
}
public void cancel() {
try {
mmSocket.close();
} catch (Exception e) {
Log.e(TAG, "close() of connect socket failed", e);
}
}
}
}
Logcat error:
W/System.err(4603): java.io.IOException: [JSR82] connect: Connection is not created (failed or aborted).
W/System.err(4603): at android.bluetooth.BluetoothSocket.connect(BluetoothSocket.java:395)
I suspect that this error could be thrown because the app is not able to get access to the active BT port,in the above mentioned test case.Reason is because I read this site : https://code.google.com/p/android/issues/detail?id=5427 (See answer #19 by dknop)
I observe that none of this issue occur on samsung s2/grand/nexus devices which I tested on.My error could also be due to MTK processors/its BT firmware/iball custom android issue.(http://redacacia.me/2012/07/17/overcoming-android-bluetooth-blues-with-reflection-method/)
Has anyone faced a similar problem? Any help would be appreciated.Many thanks !

I've tested Bluetooth connectivity on dozens of different tablets, and I've seen some VERY flaky behavior. My apps always call createRfcommSocketToServiceRecord(...) in a loop because sometimes it will fail for no apparent reason, only to succeed on a later attempt. And the API doesn't let you distinguish between transient and permanent failures. Some tablets give you a clue in the text of the error message, but others don't.
I typically try to connect 100 times at 100ms intervals, and then stop and ask the user if the device they're trying to connect to is turned on and in range. On one particular tablet model I've tested, it's not unusual for the connection to fail more than 300 times... and then it will suddenly work like nothing was ever wrong.

I have used this piece of code to make my connectivity to Bluetooth device(i.e. Bluetooth printer) stable. Now it connect 9.9 times out of 10. If still some error occurred i reset my Bluetooth programmatically again call this piece of code then it connect 10 times out of 10.
public boolean connectToPrinter(String printerName) throws IOException
{
BluetoothAdapter.getDefaultAdapter().cancelDiscovery();
BluetoothDevice device = getPrinterByName(printerName);
if (bluetoothSocket != null)
{
bluetoothSocket.close();
}
try {
Method m=device.getClass().getMethod("createRfcommSocket", new Class[]{int.class});
bluetoothSocket= (BluetoothSocket) m.invoke(device, 1);
} catch (Exception e) {
e.printStackTrace();
}
if (bluetoothSocket == null)
return false;
bluetoothSocket.connect();
return true;
}
here is the code of getPrinterByName():
private BluetoothDevice getPrinterByName(String printerName)
{
Set<BluetoothDevice> pairedDevices = BluetoothAdapter.getDefaultAdapter().getBondedDevices();
for (BluetoothDevice device : pairedDevices)
{
Log.e("","device name: "+device.getName());
if (device.getName() == null)
continue;
if (device.getName().contains(printerName))
{
remoteDevice = device;
// pairPrinter(printerName);
return remoteDevice;
}
}
return null;
}
bluetoothSocket is the Object of BluetoothSocket class. and don't forget to run this code in thread otherwise this will block your Main Thread. :-)

hi friend just replace the code to connect to bluetoothsocket by the code using reflection to
establish connection.....
private BluetoothSocket createBluetoothSocket(BluetoothDevice device) throws IOException {
if(Build.VERSION.SDK_INT >= 10){
try {
final Method m = device.getClass().getMethod("createInsecureRfcommSocketToServiceRecord", new Class[] { UUID.class });
return (BluetoothSocket) m.invoke(device, MY_UUID);
} catch (Exception e) {
Log.e(TAG, "Could not create Insecure RFComm Connection",e);
}
}
return device.createRfcommSocketToServiceRecord(MY_UUID);
}

Quote: I observed that by switching off and then switching ON the BT and then trying to establish BT connection between tablet and RN42 was happening .But now, I was not getting any input signals from RN42 to tablet,but was able to just send data from tablet to RN42.
So, before reinstalling app it WAS possible to receive input signals from rn42?