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Application are not entering "Public void run()" section

I've been create an app for Bluetooth control.
Everything is fine until I open BluetoothServerSocket to listen to an incoming connection.
here is my code:
public class ListeningThread extends Thread {
private final BluetoothServerSocket bluetoothServerSocket;
public ListeningThread() {
BluetoothServerSocket temp = null;
try {
temp = myBluetoothAdapter.listenUsingRfcommWithServiceRecord(getString(R.string.app_name), uuid);
Toast.makeText(getApplicationContext(), "Listening",
Toast.LENGTH_SHORT).show();
} catch (IOException e) {
e.printStackTrace();
}
bluetoothServerSocket = temp;
}
public void run() {
BluetoothSocket bluetoothSocket;
// This will block while listening until a BluetoothSocket is returned
// or an exception occurs
while (true) {
try {
bluetoothSocket = bluetoothServerSocket.accept();
Toast.makeText(getApplicationContext(), "Alert", <-------//the code is not run through here, there is no toast coming out
Toast.LENGTH_SHORT).show();
} catch (IOException e) {
break;
}
// If a connection is accepted
if (bluetoothSocket != null) {
runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(getApplicationContext(), "A connection has been accepted.",
Toast.LENGTH_SHORT).show();
}
});
// Manage the connection in a separate thread
try {
bluetoothServerSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
break;
}
}
}
// Cancel the listening socket and terminate the thread
public void cancel() {
try {
bluetoothServerSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
there is no error shown but when i triggered the ListeningThread() function, this line of code is running Toast.makeText(getApplicationContext(), "Listening" it is shown that my server is listening to incoming connection
but when I'm using other client to connect to this server, then client are showing "paired" but on the server there is nothing shown, but the connection was actually successfull.
from the line
//This will block while listening until a BluetoothSocket is returned//or an exception occurs and //If a connection is acceptedis not running, because the toast did not coming out.
this function is called from MainActivity Threads and was putted on a button. I don't think pasting all the code here will be good, but here is the button codes. if there is anything you need to see, simply ask me.
serverBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
ListeningThread t = new ListeningThread();
t.start();
}
});

Android: Bluetooth listening thread is blocking UI thread

my ListeningThread is freezing the UI thread of the Barometer activity although it shouldn't. I have no idea why this is happening. Help needed :)
This is my ListeningThread:
public class ListeningThread extends Thread {
String TAG = "bluetoothThread";
private final BluetoothServerSocket bluetoothServerSocket;
BluetoothAdapter bl;
public ListeningThread(BluetoothAdapter bluetoothAdapter, String appName) {
BluetoothServerSocket temp = null;
bl = bluetoothAdapter;
try {
temp = bluetoothAdapter.listenUsingRfcommWithServiceRecord(appName, Constants.MY_UUID_SECURE);
} catch (IOException e) {
e.printStackTrace();
}
bluetoothServerSocket = temp;
}
public void start() {
Log.d(TAG, "ListeningThread running");
BluetoothSocket bluetoothSocket;
//This will block while listening until a BluetoothSocket is returned or an exception occurs
while (true) {
try {
bluetoothSocket = bluetoothServerSocket.accept();
Log.d(TAG, "ListeningThread connected");
} catch (IOException e) {
break;
}
// If a connection is accepted
if (bluetoothSocket != null) {
// Manage the connection in a separate thread
try {
bluetoothServerSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
break;
}
}
}
// Cancel the listening socket and terminate the thread
public void cancel() {
try {
bluetoothServerSocket.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
And this is the activity using the thread and freezing:
public class BarometerActivity extends AppCompatActivity {
BluetoothAdapter bluetoothAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_barometer);
if (SingletonBluetoothAdapter.bluetoothAdapter == null) {
SingletonBluetoothAdapter.bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
}
bluetoothAdapter = SingletonBluetoothAdapter.bluetoothAdapter;
ListeningThread t = new ListeningThread(bluetoothAdapter, getString(R.string.app_name));
t.start();
}
}
I am sure the problem is somewhere in the run-method of the thread. I tried to surround this method with a comment and then everything runs fine.

You should put the while(true) code inside the method public void run(). Not in the public void start() as documented here https://docs.oracle.com/javase/tutorial/essential/concurrency/runthread.html

Service Socket Disconnect on Background->Foreground switch

I am writing an IRC Client. The socket connection to the IRC Server is handled via a service. I have managed to stabilize all the UI elements of the Activities in question during the orientation change, but somehow the socket that is maintained by the service is being closed during the change.
Here is what I believe to be the relevant code. Please let me know if you need to see more.
//This is the Service in question
public class ConnectionService extends Service{
private BlockingQueue<String> MessageQueue;
public final IBinder myBind = new ConnectionBinder();
public class ConnectionBinder extends Binder {
ConnectionService getService() {
return ConnectionService.this;
}
}
private Socket socket;
private BufferedWriter writer;
private BufferedReader reader;
private IRCServer server;
private WifiManager.WifiLock wLock;
private Thread readThread = new Thread(new Runnable() {
#Override
public void run() {
try {
String line;
while ((line = reader.readLine( )) != null) {
if (line.toUpperCase().startsWith("PING ")) {
SendMessage("PONG " + line.substring(5));
}
else
queueMessage(line);
}
}
catch (Exception e) {}
}
});
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
if(MessageQueue == null)
MessageQueue = new LinkedBlockingQueue<String>();
return Service.START_STICKY;
}
#Override
public IBinder onBind(Intent arg0) {
return myBind;
}
#Override
public boolean stopService(Intent name) {
try {
socket.close();
wLock.release();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return super.stopService(name);
}
#Override
public void onDestroy()
{//I put this here so I had a breakpoint in place to make sure this wasn't firing instead of stopService
try {
socket.close();
wLock.release();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
super.onDestroy();
}
public void SendMessage(String message)
{
try {
writer.write(message + "\r\n");
writer.flush();
} catch (IOException e) {
e.printStackTrace();
}
}
public String readLine()
{
try {
if(!isConnected())
return null;
else
return MessageQueue.take();
} catch (InterruptedException e) {
return "";
}
}
public boolean ConnectToServer(IRCServer newServer)
{
try {
//create a new message queue (connecting to a new server)
MessageQueue = new LinkedBlockingQueue<String>();
//lock the wifi
WifiManager wifiManager = (WifiManager) getSystemService(Context.WIFI_SERVICE);
wLock = wifiManager.createWifiLock(WifiManager.WIFI_MODE_FULL, "LockTag");
wLock.acquire();
server = newServer;
//connect to server
socket = new Socket();
socket.setKeepAlive(true);
socket.setSoTimeout(60000);
socket.connect(new InetSocketAddress(server.NAME, Integer.parseInt(server.PORT)), 10000);
writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
//run basic login scripts.
if(server.PASS != "")
SendMessage("PASS " + server.PASS);
//write nickname
SendMessage("NICK " + server.NICK);
//write username login
SendMessage("USER " + server.NICK + " 0 * :Fluffy IRC");
String line;
while ((line = reader.readLine( )) != null) {
if (line.indexOf("004") >= 0) {
// We are now logged in.
break;
}
else if (line.indexOf("433") >= 0) {
//change to alt Nick
if(!server.NICK.equals(server.ALT_NICK) && !server.ALT_NICK.equals(""))
{
server.NICK = server.ALT_NICK;
SendMessage("NICK " + server.NICK);
}
else
{
queueMessage("Nickname already in use");
socket.close();
return false;
}
}
else if (line.toUpperCase().startsWith("PING ")) {
SendMessage("PONG " + line.substring(5));
}
else
{
queueMessage(line);
}
}
//start the reader thread AFTER the primary login!!!
CheckStartReader();
if(server.START_CHANNEL == null || server.START_CHANNEL == "")
{
server.WriteCommand("/join " + server.START_CHANNEL);
}
//we're done here, go home everyone
} catch (NumberFormatException e) {
return false;
} catch (IOException e) {
return false;
}
return true;
}
private void queueMessage(String line) {
try {
MessageQueue.put(line);
} catch (InterruptedException e) {
}
}
public boolean isConnected()
{
return socket.isConnected();
}
public void CheckStartReader()
{
if(this.isConnected() && !readThread.isAlive())
readThread.start();
}
}
//Here are the relevant portions of the hosting Activity that connects to the service
//NOTE: THE FOLLOWING CODE IS PART OF THE ACTIVITY, NOT THE SERVICE
private ConnectionService conn;
private ServiceConnection mConnection = new ServiceConnection() {
#Override
public void onServiceConnected(ComponentName name, IBinder service) {
conn = ((ConnectionService.ConnectionBinder)service).getService();
Toast.makeText(main_tab_page.this, "Connected", Toast.LENGTH_SHORT)
.show();
synchronized (_serviceConnWait) {
_serviceConnWait.notify();
}
}
#Override
public void onServiceDisconnected(ComponentName name) {
conn = null;
}
};
#Override
protected void onSaveInstanceState(Bundle state){
super.onSaveInstanceState(state);
state.putParcelable("Server", server);
state.putString("Window", CurrentTabWindow.GetName());
unbindService(mConnection);
}
#Override
protected void onDestroy()
{
super.onDestroy();
if(this.isFinishing())
stopService(new Intent(this, ConnectionService.class));
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_tab_page);
localTabHost = (TabHost)findViewById(R.id.tabHostMain);
localTabHost.setup();
localTabHost.setOnTabChangedListener(new tabChange());
_serviceConnWait = new Object();
if(savedInstanceState == null)
{//initial startup, coming from Intent to start
//get server definition
server = (IRCServer)this.getIntent().getParcelableExtra(IRC_WINDOW);
server.addObserver(this);
AddTabView(server);
startService(new Intent(this, ConnectionService.class));
}
else
{
server = (IRCServer)savedInstanceState.getParcelable("Server");
String windowName = savedInstanceState.getString("Window");
//Add Needed Tabs
//Server
if(!(windowName.equals(server.GetName())))
AddTabView(server);
//channels
for(IRCChannel c : server.GetAllChannels())
if(!(windowName.equals(c.GetName())))
AddTabView(c);
//reset each view's text (handled by tabChange)
if(windowName.equals(server.GetName()))
SetCurrentTab(server.NAME);
else
SetCurrentTab(windowName);
ResetMainView(CurrentTabWindow.GetWindowTextSpan());
//Rebind to service
BindToService(new Intent(this, ConnectionService.class));
}
}
#Override
protected void onStart()
{
super.onStart();
final Intent ServiceIntent = new Intent(this, ConnectionService.class);
//check start connection service
final Thread serverConnect = new Thread(new Runnable() {
#Override
public void run() {
if(!BindToService(ServiceIntent))
return;
server.conn = conn;
conn.ConnectToServer(server);
server.StartReader();
if(server.START_CHANNEL != null && !server.START_CHANNEL.equals(""))
{
IRCChannel chan = server.FindChannel(server.START_CHANNEL);
if(chan != null)
{
AddTabView(chan);
}
else
{
server.JoinChannel(server.START_CHANNEL);
chan = server.FindChannel(server.START_CHANNEL);
AddTabView(chan);
}
}
}
});
serverConnect.start();
}
private boolean BindToService(Intent ServiceIntent)
{
int tryCount = 0;
bindService(ServiceIntent, mConnection, Context.BIND_AUTO_CREATE);
while(conn == null && tryCount < 10)
{
tryCount++;
try {
synchronized (_serviceConnWait) {
_serviceConnWait.wait(1500);
}
}
catch (InterruptedException e) {
//do nothing
}
}
return conn != null;
}
Im not entirely certain what I am doing wrong there. Obviously there's something I'm missing, haven't found yet, or haven't even thought to check. What happens though is that after the orientation change my Send command gives me this message and nothing happens:
06-04 22:02:27.637: W/System.err(1024): java.net.SocketException: Socket closed
06-04 22:02:27.982: W/System.err(1024): at com.fluffyirc.ConnectionService.SendMessage(ConnectionService.java:90)
I have no idea when the socket is getting closed, or why.
Update
I have changed the code so that rather than binding to the service and using that to start it, instead I call startService and stopService at appropriate points as well as binding to it, on the thought that the service was being destroyed when the binding was lost. This is working exactly like it was before I changed it. The socket still closes on an orientation change, and I have no idea why.
Update :- Code and description
I added the code changes recently made for Start/Stop service and START_STICKY. I also recently read a very good article explaining how the orientation change process flow works and why its NOT a bad idea to add the android:configChanges="orientation|screenSize" line to your manifest. So this fixed the orientation issue, but its still doing the same thing if I put the activity into background mode, and then bring it back to the foreground. That still follows the same Save/Destroy/Create process that the orientation does without that manifest line...and it still closes my socket, and I still don't know why.
I do know that it doesn't close the socket until the re-create process...I know this because the message queue will display messages that were received while the app was in the background, but once I bring it back forward it closes the socket and nothing else can be sent or received.

'Socket closed' means that you closed the socket and then continued to use it. It isn't a 'disconnect'.
You need to put something into that catch block. Never just ignore an exception. You might get a surprise when you see what the exception actually was.
NB Socket.isConnected() doesn't tell you anything about the state of the connection: only whether you have ever connected the Socket. You have, so it returns true.

Use a service to send/receive data through a socket connection.

I have created a client-server application that the two parties communicate using a socket connection and input/output streams to send/receive data. It all works great but only if I have just one activity that uses the connection. Since I will be having more than just one activities in my application, and after some searching around, I've concluded that I have to create a Service which will handle the socket connection and sending/receiving from the socket streams. I've never worked with Services before and I thought I'd start one step at a time. At the moment I've just created a Service that creates an instance of my Client class(which extends Thread) and starts that thread, which establishes the connection to the server.
My Client class
T_Client:
public class T_Client extends Thread {
private static final String TAG = "T_Client";
private static String serverIP = "192.168.2.3";
private static int port = 4444;
private InetAddress serverAddr = null;
private Socket sock = null;
private boolean running = false;
private ObjectInputStream in;
private ObjectOutputStream out;
private Object objIn;
public void send(MessageCustom _msg) {
if (out != null) {
try {
out.writeObject(_msg);
out.flush();
Log.i("Send Method", "Outgoing : " + _msg.toString());
} catch (IOException ex) {
Log.e("Send Method", ex.toString());
}
}
}
public void stopClient() {
Log.v(TAG,"stopClient method run");
running = false;
}
#Override
public void run() {
running = true;
try {
serverAddr = InetAddress.getByName(serverIP);
Log.i("TCP Client", "C: Connecting...");
sock = new Socket(serverAddr, port);
try {
out = new ObjectOutputStream(sock.getOutputStream());
in = new ObjectInputStream(sock.getInputStream());
Log.i(TAG, "C: Connected.");
while (running) {
objIn = in.readObject();
Log.i("Object Read Class", objIn.getClass().toString());
Log.i("Object Read", objIn.toString());
}
Log.e("RESPONSE FROM SERVER", "S: Received Message: '" + objIn + "'");
} catch (Exception e) {
Log.e(TAG, "S: Error", e);
} finally {
out.close();
in.close();
sock.close();
Log.i(TAG, "Closing socket: " + sock);
}
} catch (Exception e) {
Log.e(TAG, "C: Error", e);
}
}
}
My Service Class
MyService:
public class MyService extends Service {
private static final String TAG = "MyService";
private T_Client client;
#Override
public void onDestroy() {
Log.v(TAG, "onDestroy");
if (client != null) {
try {
client.stopClient();
} catch (Exception e) {
Log.e(TAG, "Error on close: " + e);
}
}
super.onDestroy();
Toast.makeText(this, "Service stopped", Toast.LENGTH_LONG).show();
}
#Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.v(TAG, "onStartCommand");
client = new T_Client();
client.start();
Toast.makeText(this, "Service started", Toast.LENGTH_LONG).show();
return START_STICKY;
}
#Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
}
All I do in my main activity at the moment is use a start and a stop button to start/stop the service
public void start(View v){
Log.i(TAG,"Start pressed");
Intent intent=new Intent(getBaseContext(),MyService.class);
startService(intent);
}
public void stop(View v){
Log.i(TAG,"Stop pressed");
Intent intent=new Intent(getBaseContext(),MyService.class);
stopService(intent);
}
So my questions are:
What do I have to do to send something using my Service?
How do I handle the objects that I read from the server so I can let the application know that something has been received, in real time?
Any input that could guide me towards resolving my issue is greatly appreciated.
Thank you in advance.

In case anyone else comes across this question, that has a similar problem, I managed to solve my problem by playing around with code from these two posts
Example: Communication between Activity and Service using
Messaging
How to keep the android client connected to the
server even on activity changes and send data to server?

Maintaining a TCP Connection in an AsyncTask

I'm using an AsyncTask to establish a TCP Connection and sending/receiving data through it.
My current Code looks like this at the moment:
public class NetworkTask extends AsyncTask<Void, byte[], Boolean> {
Socket nsocket; //Network Socket
InputStream nis; //Network Input Stream
OutputStream nos; //Network Output Stream
boolean bSocketStarted = false;
byte[] buffer = new byte[4096];
#Override
protected void onPreExecute() {
Log.i(TAG, "onPreExecute");
}
#Override
protected Boolean doInBackground(Void... params) { //This runs on a different thread
boolean result = false;
try {
// Connect to address
Log.i(TAG, "doInBackground: Creating socket");
SocketAddress sockaddr = new InetSocketAddress("google.de", 80);
nsocket = new Socket();
nsocket.connect(sockaddr, 5000); //10 second connection timeout
if (nsocket.isConnected()) {
bSocketStarted = true;
nis = nsocket.getInputStream();
nos = nsocket.getOutputStream();
Log.i("AsyncTask", "doInBackground: Socket created, streams assigned");
Log.i("AsyncTask", "doInBackground: Waiting for inital data...");
int read = nis.read(buffer, 0, 4096); //This is blocking
while(bSocketStarted) {
if (read > 0){
byte[] tempdata = new byte[read];
System.arraycopy(buffer, 0, tempdata, 0, read);
publishProgress(tempdata);
Log.i(TAG, "doInBackground: Got some data");
}
}
}
} catch (IOException e) {
e.printStackTrace();
Log.i(TAG, "doInBackground: IOException");
result = true;
} catch (Exception e) {
e.printStackTrace();
Log.i(TAG, "doInBackground: Exception");
result = true;
} finally {
try {
nis.close();
nos.close();
nsocket.close();
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
Log.i(TAG, "doInBackground: Finished");
}
return result;
}
public boolean SendDataToNetwork(final byte[] cmd) { //You run this from the main thread.
// Wait until socket is open and ready to use
waitForSocketToConnect();
if (nsocket.isConnected()) {
Log.i(TAG, "SendDataToNetwork: Writing received message to socket");
new Thread(new Runnable() {
public void run() {
try {
nos.write(cmd);
}
catch (Exception e) {
e.printStackTrace();
Log.i(TAG, "SendDataToNetwork: Message send failed. Caught an exception");
}
}
}
).start();
return true;
}
else
Log.i(TAG, "SendDataToNetwork: Cannot send message. Socket is closed");
return false;
}
public boolean waitForSocketToConnect() {
// immediately return if socket is already open
if (bSocketStarted)
return true;
// Wait until socket is open and ready to use
int count = 0;
while (!bSocketStarted && count < 10000) {
try {
Thread.sleep(500);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
count += 500;
}
return bSocketStarted;
}
#Override
protected void onProgressUpdate(byte[]... values) {
try {
if (values.length > 0) {
Log.i(TAG, "onProgressUpdate: " + values[0].length + " bytes received.");
String str = new String(buffer, "UTF8");
Log.i(TAG,str);
tv.setText(str);
tv.setMovementMethod(new ScrollingMovementMethod());
}
} catch (Exception e) {
e.printStackTrace();
}
finally {}
}
#Override
protected void onCancelled() {
Log.i(TAG, "Cancelled.");
}
#Override
protected void onPostExecute(Boolean result) {
if (result) {
Log.i(TAG, "onPostExecute: Completed with an Error.");
} else {
Log.i(TAG, "onPostExecute: Completed.");
}
}
}
I can instantiate the Task and call SendDataToNetwork from my activity. However, all the text I pass to SendDataToNetwork, for example, 'GET / HTTP/1.1' is continously sent to the server.
How can I modify my Code to maintain the connection in doInBackground and do nothing until I call SendDataToNetwork and after sending bytes to the server just wait until new data is ready to be sent? Basically I want to run the AsyncTask until I explicitly cancel (= close the connection) it.

nsocket.connect(sockaddr, 5000); //10 second connection timeout
if (nsocket.isConnected()) {
The test is pointless. If the socket wasn't connected, connect() would have thrown an exception.
Your read loop is also fundamentally flawed, in that it doesn't keep reading. There are standard solutions as to how to read a stream, e.g.:
while ((count = in.read(buffer)) > 0)
{
out.write(buffer, 0, count);
}
Your waitForSocketToConnect() method doesn't really do anything useful either.
You need to rethink all this.