Question

ive been thinking about this for hours and im not closer to an solution!
My thread just stops looping when im fetching a message from an server for some reason, and works perfectly when im not doing it.

This works and prints refreshing every second:

 public class ChatRoom extends Activity implements OnClickListener, Runnable {
        private Thread t = new Thread(this);

        public void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.chatroom);

                Button send = (Button) findViewById(R.id.send);
                send.setOnClickListener(this);

                Intent receiver = getIntent();
                String host = receiver.getStringExtra("Host");
                int port = receiver.getIntExtra("Port", 4456);


                try
                {
                    socket = new Socket(host, port);
                    this.receive = new BufferedReader(new InputStreamReader(this.socket.getInputStream()));
                    this.send = new PrintWriter(this.socket.getOutputStream(), true);

                } 
                catch(IOException ioe) { System.out.println(ioe); }
                t.start();


            }

            public void run()
            {
                String message = "";

                while(true)
                {
                    try
                    {
                        // message = receive.readLine(); BufferedReader
                        t.sleep(1000);
                    } 
                    //catch(IOException ioe)            { System.out.println(ioe); }
                    catch (NullPointerException npe)    { System.out.println(npe); } 
                    catch (InterruptedException e)      { System.out.println(e);   }

                    System.out.println("Refreshing...");

                }
            }

And when i use my commented code, it actually works and i get a message from the server but it loops just once! Why is that?

Output:
Server Message
Refreshing...

I get no Exception or errors, but i had an error before with some similar code that said that i cant change UI on other threads. So ive been looking at some runOnUiThread but it didnt make it better, and i dont know why it should 🙁

Answer 1

The method BufferedReader.readLine() blocks until a newline character is received. If there is no newline in your receiver stream it will block forever.