import org.phoenixframework.channels.*;

Socket socket;
Channel channel;

// To connect with authentication
String authToken = "abc123"
Uri.Builder url = Uri.parse( "ws://localhost:4000/socket/websocket" ).buildUpon();
url.appendQueryParameter( "auth_token", authToken );
socket = new Socket(url.build().toString());
socket.connect();

channel = socket.chan("rooms:lobby", null);

channel.join()
.receive("ignore", new IMessageCallback() {
    @Override
    public void onMessage(Envelope envelope) {
        System.out.println("IGNORE");
    }
})
.receive("ok", new IMessageCallback() {
    @Override
    public void onMessage(Envelope envelope) {
        System.out.println("JOINED with " + envelope.toString());
    }
});

channel.on("new:msg", new IMessageCallback() {
    @Override
    public void onMessage(Envelope envelope) {
        System.out.println("NEW MESSAGE: " + envelope.toString());
    }
});

channel.on(ChannelEvent.CLOSE.getPhxEvent(), new IMessageCallback() {
    @Override
    public void onMessage(Envelope envelope) {
        System.out.println("CLOSED: " + envelope.toString());
    }
});

channel.on(ChannelEvent.ERROR.getPhxEvent(), new IMessageCallback() {
    @Override
    public void onMessage(Envelope envelope) {
        System.out.println("ERROR: " + envelope.toString());
    }
});

//Sending a message. This library uses Jackson for JSON serialization
ObjectNode node = new ObjectNode(JsonNodeFactory.instance)
        .put("user", "my_username")
        .put("body", message);

channel.push("new:msg", node);