wss_helidon_se.java

    public static void main(String[] args) {
        WebServer.builder(
                        Routing.builder()
                                .register("/ws", TyrusSupport.builder()
                                        .register(ServerEndpointConfig.Builder.create(WsEndpoint.class, "/echo").build())
                                        .build()
                                )
                )
                .port(8080)
                .tls(WebServerTls.builder()
                        .privateKey(KeyConfig.keystoreBuilder()
                                .keystorePassphrase("password")
                                .keystore(Resource.create("server.p12"))
                                .build()))
                .build()
                .start();
    }

    public static class WsEndpoint extends Endpoint {
        @Override
        public void onOpen(Session session, EndpointConfig config) {
            var remote = session.getBasicRemote();
            session.addMessageHandler(new MessageHandler.Partial<String>() {
                @Override
                public void onMessage(String message, boolean last) {
                    try {
                        remote.sendText("Did you say " + message + "?");
                        remote.flushBatch();
                    } catch (IOException e) {
                        throw new RuntimeException(e);
                    }
                }
            });
        }
    }