Agfdhyk

I want to make a chat module on android application. Simple chat for users and administrator for communications. Server working with node js. And client-side using java-WebSocket-client.

Firstly I create web socket server on node js.

const Messages = require('./models/index').Messages;

const WebSocketServer = require("ws").Server;



module.exports = (server) => {

    const wss = new WebSocketServer({server: server});



    wss.on("connection", function (ws) {



    console.info("websocket connection open");



    ws.on("join", function (userId) {

        console.log(userId +" : has joined the chat "  );



        Messages.findAll({

          attributes: ['message', 'roomId', 'senderId','createdAt'],

          where: { roomId: userId },

          order: [ ['createdAt', 'ASC'] ]

        }).then(message => {

          ws.send('get_last_messages', message);

        });

    });



    ws.on('message', (data) => {  

    console.log("websocket received a message");

    console.log(data);



    ws.on("close", function () {

        console.log("websocket connection close");

    });

});

console.log("websocket server created");

Android chatActivity (implementation "org.java-websocket:Java-WebSocket:1.3.9"):

public class MainActivity extends Activity {

    private WebSocketClient mWebSocketClient;



    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);



        connectWebSocket();

    }

private void connectWebSocket() {

        URI uri;

        try {

            uri = new URI("ws://websockethost:8080");

        } catch (URISyntaxException e) {

            e.printStackTrace();

            return;

        }



        mWebSocketClient = new WebSocketClient(uri) {

            @Override

            public void onOpen(ServerHandshake serverHandshake) {

                Log.i("Websocket", "Opened");

                mWebSocketClient.send("Hello from " + Build.MANUFACTURER + " " + Build.MODEL);

            }



            @Override

            public void onMessage(String s) {

                final String message = s;

                runOnUiThread(new Runnable() {

                    @Override

                    public void run() {

                        TextView textView = (TextView)findViewById(R.id.messages);

                        textView.setText(textView.getText() + "n" + message);

                    }

                });

            }



            @Override

            public void onClose(int i, String s, boolean b) {

                Log.i("Websocket", "Closed " + s);

            }



            @Override

            public void onError(Exception e) {

                Log.i("Websocket", "Error " + e.getMessage());

            }

        };

        mWebSocketClient.connect();

    }



    public void sendMessage(View view) {

        EditText editText = (EditText)findViewById(R.id.message);

        mWebSocketClient.send(editText.getText().toString());

        editText.setText("");

}

But it is not working. Connection closed.

How to create nodejs websocket server and android websocketclient right way?

You need to add the internet permission the AndroidManifest.xml and it looks like you do network communication on the MainThread.
https://developer.android.com/training/basics/network-ops/connecting