Reactive consuming a web socket using RxJava, Java8 and Tyrus client

WebSocketClientReactive.java

import org.glassfish.tyrus.ext.client.java8.SessionBuilder;
import rx.Observable;

import javax.websocket.Session;
import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.concurrent.CountDownLatch;

public class WebSocketClientReactive {
    private static CountDownLatch messageLatch = new CountDownLatch(1);

    public static void main(String[] args) throws Exception {
        Observable<Object> observable = Observable.create(subscriber -> {
            try {
                final Session[] session = new Session[1];
                //this is an echo WSS
                new SessionBuilder().uri(new URI("wss://sandbox.kaazing.net/echo"))
                        .onOpen((session1, endpointConfig) -> {
                            System.out.println("Connection open");
                            session[0] = session1;
                            try {
                                session[0].getBasicRemote().sendText("hello");
                            } catch (IOException e) {
                                e.printStackTrace();
                            }
                        })
                        .messageHandler(String.class, (t) -> {
                            try {
                                Thread.sleep(100);
                                session[0].getBasicRemote().sendText("hello");
                            } catch (IOException | InterruptedException e) {
                                e.printStackTrace();
                            }
                            subscriber.onNext(t);
                        })
                        .onError((session1, throwable) -> {
                            System.out.println("Aborted, the error is: " + throwable.getMessage());
                            messageLatch.countDown();
                        })
                        .connectAsync();
            } catch (URISyntaxException e) {
                e.printStackTrace();
            }
        });

        //subscribe
        observable.subscribe(o -> System.out.println("Received message: " + o));

        //waits until you hit Ctrl+C
        messageLatch.await();
    }

}