Подключение к сервису

@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
 
    @Override
    public void configureMessageBroker(MessageBrokerRegistry config) {
        config.enableSimpleBroker("/topic");
        config.setApplicationDestinationPrefixes("/app");
    }
 
    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        registry.addEndpoint("/message").withSockJS();
    }

    @MessageMapping("/hello")
    @SendTo("/topic/greeting")
    public Message greetings(Message message) {
        System.out.println("websocket");
         return  messageRepo.save(message);
    }

@Entity
public class Message {
 
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
 
    private String name;
    private String text;
 
    @Override
    public String toString() {
        return "Message{" +
                "Id=" + id +
                ", name='" + name + '\'' +
                ", text='" + text + '\'' +
                '}';
    }
 
    public void setName(String name) {
        this.name = name;
    }
 
    public void setText(String text) {
        this.text = text;
    }
 
    public String getName() {
        return name;
    }
 
    public String getText() {
        return text;
    }
 
    public void setId(Long id) {
        this.id = id;
    }
 
    public Long getId(){
        return id;
    }
}

public void connect() throws InterruptedException {
 
    Request request = new Request.Builder()
            .url("wss://myserver-ioan.herokuapp.com/message")
            .build();
 
    OkHttpClient client = new OkHttpClient();
    WebSocket ws = client.newWebSocket(request, new EchoWebSocketListener());
 
 
 
    client.dispatcher().executorService().shutdown();
 
    }

class EchoWebSocketListener extends WebSocketListener {
    private static final int NORMAL_CLOSURE_STATUS = 1000;
    private JsonAdapter<Message> adapter;
 
    EchoWebSocketListener()
    {
        Moshi moshi = new Moshi.Builder().build();
        adapter = moshi.adapter(Message.class);
    }
 
    @Override
    public void onOpen(WebSocket webSocket, Response response) {
        super.onOpen(webSocket, response);
        System.out.println("open");
    }
 
 
    @Override
    public void onMessage(WebSocket webSocket, String text) {
            System.out.println("onMessage " + text);
    }
 
    @Override
    public void onClosing(WebSocket webSocket, int code, String reason) {
        webSocket.close(NORMAL_CLOSURE_STATUS, null);
        System.out.println("on Close ");
    }
    @Override
    public void onFailure(WebSocket webSocket, Throwable t, Response response) {
        System.out.println("on Failure " + t.getMessage() + " " + response.toString());
    }
}