Nrthugu

I'm developing an App that is meant to receive weight measures from industrial scales, one, two or more scales. The weight of each scale is sent through a RS232 interface continuously (I receive every 100 milliseconds the weight from the scale, this means that idle time is low. Once I start receiving the weight from the scale it doesn't stop) using a WiFi Serial adapter. I'm using a TCP Connection Socket and it works fine if I try to get the weight one scale at a time. What I try to achieve is this: I want to listen to two or four scales at the same time and update the UI in real time as I get the weight from the scale. (If I read the weight one scale at the time it works fine). I tried multithreading, ThreadPoolExecutor, ThreadHandlers, etc but I got several errors (pretty sure I didn't implement them correctly I'm new to multithreading). This is the code at the moment:

The Connection Class receives the weight from the scales. I communicate the weight received through an interface to the other classes

public class Connection implements Runnable {

public static final String LOG_TAG = Connection.class.getSimpleName();

public interface ConnectionDefinition {

    public ConnectionReader createReader(int timeout) throws IOException;



    public String getNameOrAddress();

}



public interface Listener {

    public void onException(Exception e);



    public void postWeight(double weight, boolean steady);

}



private ConnectionReader m_Reader;

private Listener m_Listener = s_NullListener;

private final ConnectionDefinition m_ConnectionDefinition;



private volatile boolean m_Continue = false;



private static final int s_Timeout = 5000;



public Connection(final ConnectionDefinition connectionDef) {

    m_ConnectionDefinition = connectionDef;

    start();

}



@Override

public void run() {

    m_Continue = true;

    while (m_Continue) {

        try {

            m_Reader = m_ConnectionDefinition.createReader(s_Timeout);

            final Result result = new Result();



            while (m_Continue) {

                m_Reader.read(result);



                final double weight = result.weight;

                final boolean steady = result.steady;



                Log.e(LOG_TAG, "Connection!!! " + String.valueOf(weight));



                m_Listener.postWeight(weight, steady);

            }

        } catch (final IOException e) {

            handleException(e);

        } finally {

            if (m_Reader != null)

                try {

                    m_Reader.close();

                } catch (final IOException ignored) {

                    // ignored

                }

            m_Reader = null;

        }

    }

}



private void handleException(final Exception e) {

    if (m_Continue) {

        m_Listener.onException(e);

        try {

            Thread.sleep(s_Timeout);

        } catch (final InterruptedException e1) {

        }

    }

}



public void start() {

    if (running())

        throw new IllegalStateException("Connection already running");



    final String name = m_ConnectionDefinition.getNameOrAddress();

    //Log.e(LOG_TAG, "Estoy en START! ");

    new Thread(this, "Scale Connection: " + name).start();

}



public void stop() {

    m_Continue = false;

    if (m_Reader != null) {

        try {

            m_Reader.stop();

        } catch (final IOException e) {

        }

    }

    //Log.e(LOG_TAG, "Estoy en STOP! ");

}



public boolean running() {

    return m_Continue;

}



public void setListener(final Listener listener) {

    if (listener != null)

        m_Listener = listener;

    else

        m_Listener = s_NullListener;

}



public void removeListener() {

    m_Listener = s_NullListener;

}



public ConnectionDefinition connectionDefinition() {

    return m_ConnectionDefinition;

}



private static Listener s_NullListener = new Listener() {

    @Override

    public void onException(final Exception e) {

    }



    @Override

    public void postWeight(final double weight, final boolean steady) {

    }

};



}

I created a method, where I try to listen to the different weight measures and Update the UI (this method works with one listener at the time. It updates the UI correctly):

    private void connectionListener(){



        /*I GET THE CONNECTIONS DEFINED*/



        final List<ConnectionDefinition> connectionDefinition = Persistor.getInstance().connectionDefinitions();

        final ConnectionDefinition conDef = connectionDefinition.get(0);



/*MY APPROACH IS TO CREATE RUNNABLES TO PUT THE TO WORK IN DIFFERENT THREATS. UNTIL NOW IT DIDNT WORK*/



runnable1 = (new Runnable() {

            final Connection connection1 = new Connection(conDef);

            @Override

            public void run() {

                if(!connection1.running()) connection1.start();

                connection1.setListener(new Connection.Listener() {

                    @Override

                    public void postWeight(final double weight, final boolean steady) {

                        mHandler1.post(new Runnable() {

                            public void run() {

                                if(!Double.isNaN(weight)){

                                    Log.e(LOG_TAG, "Runnable 1 !!!");

                                    inputPesoRuedaDelanteraIzquierda.setText(String.valueOf(weight));

                                    //connection1.stop();

                                }

                            }

                        });

                    }

                    @Override

                    public void onException(final Exception e) {

                        e.printStackTrace();

                        //showMessage("Reintentando en 5 segs...");

                    }

                });

                /*

                try {

                    Thread.sleep(300);

                } catch (InterruptedException e) {

                    e.printStackTrace();

                }*/

            }

        });



        runnable2 = (new Runnable() {

            final Connection connection2 = new Connection(conDef);

            @Override

            public void run() {

                if(!connection2.running()) connection2.start();

                connection2.setListener(new Connection.Listener() {

                    @Override

                    public void postWeight(final double weight, final boolean steady) {

                        mHandler1.post(new Runnable() {

                            public void run() {

                                if(!Double.isNaN(weight)){

                                    Log.e(LOG_TAG, "Runnable 2 !!!");

                                    inputPesoRuedaDelanteraDerecha.setText(String.valueOf(weight));

                                    //connection2.stop();

                                }

                            }

                        });

                    }



                    @Override

                    public void onException(final Exception e) {

                        e.printStackTrace();

                        //showMessage("Reintentando en 5 segs...");

                    }

                });

                /*

                try {

                    Thread.sleep(300);

                } catch (InterruptedException e) {

                    e.printStackTrace();

                }*/

            }

        });



        worker = new WorkerThreadPool();

        worker.execute(runnable1);

        worker.execute(runnable2);



        /*

        Executor executor = new ThreadPerTaskExecutor();

        executor.execute(runnable1);

        executor.execute(runnable2);

        */

        //new Thread(runnable1).start();

        //new Thread(runnable2).start();





    }

As you can see I tried different approaches. I need help to implement the correct one I'm open to other ideas (Maybe listener iterators, even though I like the idea of multithreading)