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Jetty 9 WebSocket client issue when using secure connection

I'm writing a WebSocket client in a java application, using the Jetty 9.4.18 libraries.
I'm pretty new to WebSockets, so I started testing using the two sample classes from the Jetty documentation, connecting to echo.websocket.org
The test runs fine when I connect without SSL, but if fails when the connection is done to wss://echo.websocket.org
I always get the same exception:
java.io.EOFException: HttpConnectionOverHTTP#50371e9d::DecryptedEndPoint#6dc65fc2{echo.websocket.org/174.129.224.73:443<->/192.168.1.34:60521,OPEN,fill=-,flush=C,to=226/0}
at org.eclipse.jetty.client.http.HttpReceiverOverHTTP.earlyEOF(HttpReceiverOverHTTP.java:338)
at org.eclipse.jetty.http.HttpParser.parseNext(HttpParser.java:1551)
at org.eclipse.jetty.client.http.HttpReceiverOverHTTP.shutdown(HttpReceiverOverHTTP.java:209)
at org.eclipse.jetty.client.http.HttpReceiverOverHTTP.process(HttpReceiverOverHTTP.java:147)
at org.eclipse.jetty.client.http.HttpReceiverOverHTTP.receive(HttpReceiverOverHTTP.java:73)
at org.eclipse.jetty.client.http.HttpChannelOverHTTP.receive(HttpChannelOverHTTP.java:133)
at org.eclipse.jetty.client.http.HttpConnectionOverHTTP.onFillable(HttpConnectionOverHTTP.java:155)
at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:305)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103)
at org.eclipse.jetty.io.ssl.SslConnection$DecryptedEndPoint.onFillable(SslConnection.java:411)
at org.eclipse.jetty.io.ssl.SslConnection.onFillable(SslConnection.java:305)
at org.eclipse.jetty.io.ssl.SslConnection$2.succeeded(SslConnection.java:159)
at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:103)
at org.eclipse.jetty.io.ChannelEndPoint$2.run(ChannelEndPoint.java:118)
at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:765)
at org.eclipse.jetty.util.thread.QueuedThreadPool$2.run(QueuedThreadPool.java:683)
at java.lang.Thread.run(Thread.java:748)
It looks like the server closes without answering to the handshake request.
I am aware of SslContextFactory, but my understanding is that it should be used only if you need your own TrustStore or KeyStore, or for other special cases.
Note also that after some failed attempt I downloaded another websocket implementation from https://github.com/TooTallNate/Java-WebSocket, and it works fine with both ws and wss, without setting anything specific for SSL.
However for this project I'm bind to use Jetty.
The code I'm using is exactly the sample from Jetty documentation at https://www.eclipse.org/jetty/documentation/9.4.x/jetty-websocket-client-api.html
the only change I did was to add an onError method to SimpleEchoSocket, that dumps the full exception stack.
Am I missing something?
Thanks in advance!

Unfortunately, websocket.org (and Kaazing host/proxy) has a bunch of TLS issues at this point in time, so using their public servers are not sane choice right now.
Here's a different demo, also using TLS and WebSocket, against a stackexchange server with a proper and sane TLS/SSL implementation.
This was written against Jetty 9.4.18.v20190429
package org.eclipse.jetty.demo;
import java.net.URI;
import java.util.concurrent.Future;
import org.eclipse.jetty.client.HttpClient;
import org.eclipse.jetty.util.component.LifeCycle;
import org.eclipse.jetty.util.log.Log;
import org.eclipse.jetty.util.log.Logger;
import org.eclipse.jetty.util.ssl.SslContextFactory;
import org.eclipse.jetty.websocket.api.Session;
import org.eclipse.jetty.websocket.api.annotations.OnWebSocketClose;
import org.eclipse.jetty.websocket.api.annotations.OnWebSocketConnect;
import org.eclipse.jetty.websocket.api.annotations.OnWebSocketError;
import org.eclipse.jetty.websocket.api.annotations.OnWebSocketMessage;
import org.eclipse.jetty.websocket.api.annotations.WebSocket;
import org.eclipse.jetty.websocket.client.WebSocketClient;
#WebSocket
public class SecureClientSocket
{
private static final Logger LOG = Log.getLogger(SecureClientSocket.class);
public static void main(String[] args)
{
String url = "wss://qa.sockets.stackexchange.com/";
SslContextFactory ssl = new SslContextFactory.Client();
ssl.setEndpointIdentificationAlgorithm("HTTPS");
HttpClient http = new HttpClient(ssl);
WebSocketClient client = new WebSocketClient(http);
try
{
http.start();
client.start();
SecureClientSocket socket = new SecureClientSocket();
Future<Session> fut = client.connect(socket, URI.create(url));
Session session = fut.get();
session.getRemote().sendString("Hello");
session.getRemote().sendString("155-questions-active");
}
catch (Throwable t)
{
LOG.warn(t);
}
finally
{
stop(http);
stop(client);
}
}
private static void stop(LifeCycle lifeCycle)
{
try
{
lifeCycle.stop();
}
catch (Exception e)
{
e.printStackTrace();
}
}
#OnWebSocketConnect
public void onConnect(Session sess)
{
LOG.info("onConnect({})", sess);
}
#OnWebSocketClose
public void onClose(int statusCode, String reason)
{
LOG.info("onClose({}, {})", statusCode, reason);
}
#OnWebSocketError
public void onError(Throwable cause)
{
LOG.warn(cause);
}
#OnWebSocketMessage
public void onMessage(String msg)
{
LOG.info("onMessage() - {}", msg);
}
}

Java WebSocket: How can I test a Server WebSocket endpoint without writing a client [closed]

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I am using Glassfish server to host a basic Web Socket server using javax.websocket.
Here is the server code:
import javax.websocket.*;
import javax.websocket.server.ServerEndpoint;
import java.io.IOException;
#ServerEndpoint("/websocket/server")
public class WebSocketServer {
#OnOpen
public void onOpen(Session session) {
System.out.println(String.format("Connection Established::%s", session.getId()));
RemoteEndpoint.Basic remoteEndpoint = session.getBasicRemote();
session.addMessageHandler(new ServerMessageHandler(remoteEndpoint));
}
#OnClose
public void onClose(Session session) {
System.out.println(String.format("Connection closed::%s", session.getId()));
}
#OnError
public void onError(Throwable t) {
System.out.println(t.toString());
}
#OnMessage
public void onMessage(Session session, String message) {
System.out.println(String.format("Received message::%s - sessionId::%s", message, session.getId()));
}
private class ServerMessageHandler implements MessageHandler.Whole<String> {
private RemoteEndpoint.Basic _remoteEndpoint;
ServerMessageHandler(RemoteEndpoint.Basic remoteEndpoint) {
this._remoteEndpoint = remoteEndpoint;
}
public void onMessage(String message) {
try {
_remoteEndpoint.sendText(message);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
And here is the console app that runs the server:
import org.glassfish.tyrus.server.Server;
import javax.websocket.DeploymentException;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class Main {
public static void main(String[] args) {
runServer();
}
private static void runServer() {
Server server = null;
try {
server = new Server("localhost", 8080, "/websocket", null, WebSocketServer.class);
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
server.start();
System.out.println("Please press a key to stop the server.");
reader.readLine();
} catch (IOException e) {
throw new RuntimeException(e);
} catch (DeploymentException e) {
throw new RuntimeException(e);
} finally {
if (server != null) {
server.stop();
}
}
}
}
My question is when I run this console app and it runs the Websocket server, what is the best way I can test my endpoint to verify that it's working or even debug into the server code (onOpen, onClose, etc). I was attempting to use Postman to hit ws:\localhost:8080\websocket\server, but that doesn't work. I am completely new to Web Sockets, so my thinking could be wrong due to lack of experience and knowledge with the technology.
Thanks.

Postman doesn't support it, but WebSocket King provides a similar interface that is designed specifically for web sockets.

https://postwoman.io/ also supports websocket connections, however it's kinda inconvinient to use as it even bans copy from response
personally, I use https://www.websocket.org/echo.html page with custom URL, but if you want code snippets, pre and post-request testing, I would recommend to write your own client

Java WebSocket session resulting to null after onOpen

I am using websockets for the first time on a javafx project, when I start the program the session is set to the local variable session, but after when I call the sendMessage function the session is back to null. Below please find my client class
package myclient;
import java.io.IOException;
import java.io.InputStream;
import java.net.URI;
import java.util.logging.Level;
import java.util.logging.Logger;
import javafx.application.Application;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.stage.Stage;
import javax.websocket.ClientEndpoint;
import javax.websocket.ContainerProvider;
import javax.websocket.DeploymentException;
import javax.websocket.OnClose;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.WebSocketContainer;
#ClientEndpoint
public class Client extends Application {
private static final Logger LOGGER = Logger.getLogger(Client.class.getName());
private Session session;
#OnOpen
public void onOpen(Session session){
this.session = session;
System.out.println("Opened Session " + this.session);
}
#OnClose
public void onClose(){
System.out.println("Closed Session " + this.session);
}
#OnMessage
public void onMessage(String msg){
System.out.println("Websocket message received! " + msg);
}
#Override
public void start(Stage stage) throws Exception {
Parent root = FXMLLoader.load(getClass().getResource("FXMLClient.fxml"));
Scene scene = new Scene(root);
connectToWebSocket();
stage.setScene(scene);
stage.show();
}
private void connectToWebSocket() {
System.out.println("Client WebSocket initialized>> " + this.session);
WebSocketContainer container = ContainerProvider.getWebSocketContainer();
try {
URI uri = URI.create("ws://localhost:8080/Server/endpoint");
container.connectToServer(this, uri);
}
catch (DeploymentException | IOException ex) {
LOGGER.log(Level.SEVERE, null, ex);
System.exit(-1);
}
}
public void sendMessage(String message) throws IOException{
if(this.session != null){
System.out.println(message + ", " + this.session);
this.session.getBasicRemote().sendText(message);
}
else {
System.out.println("Session is null");
}
}
public static void main(String[] args) {
launch(args);
}
}
Any suggestions?
Thanks in advance

I think I now do know the answer to this.
You are probably using tomcat or some other server for this. When you see "tomcat" in this answer, please insert the name of your actually used server.
When a connection to your websocket is opened, tomcat will create an instance of the websocket (your Client) class by itself. This means, the onOpen-Method will be called and it will look as if it was you who created the instance, who opened the connection, when really you did not. Tomcat did.
This in turn means, that when you call sendMessage on your Client instance, the session will be null, because this object never connected anywhere.
Oh, and you don't have access to the connected instance that was created by tomcat.
One way of fixing this would be to do all the work inside the onOpen-Method, however that is not practical. You may want to put the work in another method and call it from onOpen. That way, the instance created by tomcat will do the necessary work.
In my project I needed to poll on an MQTT-Topic and render the data on a website (university assignment). I did the polling in a separate class, resulting in hard to debug errors whenever trying to send received data with my sendMessage-method.
I hope this answer does clear this up a little, if not for you, maybe at least for future generations having the same university assignment...

WebSocket and Endpoint

My IDE : NetBeans, GlassFish.
I am trying to understand how GlassFish execute and run the Endpoint!
I understand Glassfish as a webserver creates new Endpoint instance for each connection, and the Set : peers in the code appears as one global variable for every instance of endpoint.
My question is : how to add another global variable(s) so every instance of endpoint can access it?
enter code here
import java.io.IOException;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import javax.websocket.OnClose;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.ServerEndpoint;
#ServerEndpoint("/echo")
public class EchoServer {
/**
* #OnOpen allows us to intercept the creation of a new session.
* The session class allows us to send data to the user.
* In the method onOpen, we'll let the user know that the handshake was
* successful.
*/
private static final Set<Session > peers = Collections.synchronizedSet(new HashSet<Session >());
#OnOpen
public void onOpen(Session session){
System.out.println(session.getId() + " has opened a connection");
try {
peers.add(session);
session.getBasicRemote().sendText("Connection Established");
} catch (IOException ex) {
ex.printStackTrace();
}
}
#OnMessage
public void onMessage(String message, Session session) throws IOException{
System.out.println("Message from " + session.getId() + ": " + message);
for (Session peer : peers) {
peer.aplayer.getBasicRemote().sendText(" Message from " + session.getId()+" : "+message);
}
}`enter code here`
#OnClose
public void onClose(Session session){
System.out.println("Session " +session.getId()+" has ended");
peers.remove(session);
}
}

Websocket example won't work

I try run this example:
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.websocket.OnClose;
import javax.websocket.OnError;
import javax.websocket.OnMessage;
import javax.websocket.OnOpen;
import javax.websocket.Session;
import javax.websocket.server.ServerEndpoint;
#ServerEndpoint(value = "/chat")
public class ChatServer {
private static final Logger LOGGER =
Logger.getLogger(ChatServer.class.getName());
#OnOpen
public void onOpen(Session session) {
LOGGER.log(Level.INFO, "New connection with client: {0}",
session.getId());
}
#OnMessage
public String onMessage(String message, Session session) {
LOGGER.log(Level.INFO, "New message from Client [{0}]: {1}",
new Object[] {session.getId(), message});
return "Server received [" + message + "]";
}
#OnClose
public void onClose(Session session) {
LOGGER.log(Level.INFO, "Close connection for client: {0}",
session.getId());
}
#OnError
public void onError(Throwable exception, Session session) {
LOGGER.log(Level.INFO, "Error for client: {0}", session.getId());
}
}
I use Tomcat 7.0.47, I check link: ws://localhost/Tests/chat.
Do I need register this websocket or add some things in web.xml?
Any idea why is not working for me?

I had the same problem trying to use WebSocket API on Tomcat 7.0.47. The error message being displayed client side wasn't any help at all and my server side endpoint was never being created.
After much wasted time I found it was due to way I had set the dependency for javax.websocket-api. I'm using Maven which has the default scope as compile which causes problems as Tomcat has the websocket-api.jar in its lib folder. Setting the dependency to provided solved it.
<dependency>
<groupId>javax.websocket</groupId>
<artifactId>javax.websocket-api</artifactId>
<version>1.0</version>
<scope>provided</scope>
</dependency>
Hope this helps
It's also worth noting that if running behind Apache you will need mod_proxy_wstunnel and if using IIS you will need version 8.0 as anything prior does not support websockets.