@Retention(value=RUNTIME) @Target(value=TYPE) @Documented @Import(value=DelegatingWebSocketMessageBrokerConfiguration.class) public @interface EnableWebSocketMessageBroker
@Configuration class to enable broker-backed
 messaging over WebSocket using a higher-level messaging sub-protocol.
 
 @Configuration
 @EnableWebSocketMessageBroker
 public class MyWebSocketConfig {
 }
 
 Customize the imported configuration by implementing the
 WebSocketMessageBrokerConfigurer interface:
 
 @Configuration
 @EnableWebSocketMessageBroker
 public class MyConfiguration implements WebSocketMessageBrokerConfigurer {
     @Override
     public void registerStompEndpoints(StompEndpointRegistry registry) {
         registry.addEndpoint("/portfolio").withSockJS();
     }
     @Override
     public void configureMessageBroker(MessageBrokerRegistry registry) {
         registry.enableStompBrokerRelay("/queue/", "/topic/");
         registry.setApplicationDestinationPrefixes("/app/");
     }
 }