Why InputStream is stopping my application?

Question

I have an Android App that talks with a Java Server between socket connection. When server is running, there's no problem. I send something from Android and server answer. I get response and put it in Toast. Looks great! But if i stop running server, Android stay waiting for answer and all application stop working. Strange is the fact that application in running inside a thread, so i think its not supposed to happen. I'd like to know if is there some way to avoid it to crash application and some way to say to app's user that server doesn't respond. I'm sorry if is there some silly mistake, i'm just new in Java. The code:

        public void onClick(DialogInterface dialog, int whichButton) {

            InetAddress ia;
            try {

                ia = InetAddress.getByName("192.168.3.101");
                s = new Socket(ia,12346);
                Thread t = new Thread(new doComms(s));
                t.start();
            } catch (UnknownHostException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }});

And the class doComms:

class doComms implements Runnable {

        private Socket s;
        String line,inp;

        doComms(Socket server) {
          this.s=server;
        }

        public void run () {

          inp="";

          try {
            // Get input from the client
            DataInputStream in = new DataInputStream (s.getInputStream());
            PrintStream out = new PrintStream(s.getOutputStream());
            out.println(input.getText().toString()+"\n.");


            while((line = in.readLine()) != null && !line.equals(".")) {
              inp=inp + line;
            }

            runOnUiThread(new Runnable() {
                public void run() {
                    if(inp.equals("ok")){
                        Toast.makeText(Inicio.this,"Mensagem enviada com sucesso",Toast.LENGTH_LONG).show();
                    }else{
                        Toast.makeText(Inicio.this,"Falha ao enviar mensagem",Toast.LENGTH_LONG).show();
                    }
               }
           });

            Log.v("inp", inp);
            Log.v("type",inp.getClass().toString()); 

            s.close();


          } catch (IOException ioe) {
            System.out.println("IOException on socket listen: " + ioe);
            ioe.printStackTrace();
          }
        }

    }

This could also be interesting for you: http://stackoverflow.com/questions/9525972/add-a-timeout-when-creating-a-new-socket — Ben, Feb 05 '14 at 18:01
No error, no exception. Log shows nothing. Just the application shows a dialog saying it stoped and asking if i wanna close app or wait — Giovanni Oliveira, Feb 05 '14 at 18:06

score 0 · Answer 1 · answered Feb 05 '14 at 21:59

0

You're using println() to send a line that already contains a newline. That will result in two newlines being sent, which will probably confuse the peer and possibly cause it to return something unexpected, which your code may not be coping with correctly.

answered Feb 05 '14 at 21:59

user207421

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I'm not sure if this is the answer for my problem. I mean, i send code from android, passing by server, and get it back in android the spected way. But if the server is not runnig, the application stop responding. I suppose its not to happen cause this function is caught inside a Thread. – Giovanni Oliveira Feb 05 '14 at 23:43

Why InputStream is stopping my application?

1 Answers1

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