How to send message to user when he connects to spring websocket

Question

I want to send message to user when he connects to spring websocket, I\'ve

@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig extends          


        

Answer 1

you need a Websocketconfig file:

package mx.config.ws;
@EnableScheduling
@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer {
   @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
       registry.addEndpoint("/chat").withSockJS()
    }

    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
    ...
    }
}

And declare a nother @Configuration file:

package mx.config.ws;
@Configuration
public class WebSocketHandlersConfig {

    @Bean
    public StompConnectEvent webSocketConnectHandler() {
        return new StompConnectEvent();
    }

    @Bean
    public StompDisconnectEvent webSocketDisconnectHandler() {
        return new StompDisconnectEvent();
    }
}

Next create implementation of ApplicationListener interface. Automatically you will intercept the STOMP connections

package mx.config.ws;
public class StompConnectEvent implements ApplicationListener {

    @Override
    public void onApplicationEvent(SessionConnectEvent event) {

         StompHeaderAccessor sha = StompHeaderAccessor.wrap(event.getMessage());

         System.out.println("StompConnectEvent::onApplicationEvent()    sha.getSessionId(): "+sha.getSessionId()+" sha.toNativeHeaderMap():"+sha.toNativeHeaderMap());


         //String  company = sha.getNativeHeader("company").get(0);
         //logger.debug("Connect event [sessionId: " + sha.getSessionId() +"; company: "+ company + " ]");



         // HERE YOU CAN MAYBE SEND A MESSAGE

    }

}

Check this link for a bout of information:
http://www.sergialmar.com/2014/03/detect-websocket-connects-and-disconnects-in-spring-4/