Dots as Separators

When messages are routed to @MessageMapping methods, they are matched with AntPathMatcher. By default, patterns are expected to use slash (/) as the separator. This is a good convention in web applications and similar to HTTP URLs. However, if you are more used to messaging conventions, you can switch to using dot (.) as the separator.

The following example shows how to do so:

  • Java

  • Kotlin

  • Xml

@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfiguration implements WebSocketMessageBrokerConfigurer {

	// ...

	@Override
	public void configureMessageBroker(MessageBrokerRegistry registry) {
		registry.setPathMatcher(new AntPathMatcher("."));
		registry.enableStompBrokerRelay("/queue", "/topic");
		registry.setApplicationDestinationPrefixes("/app");
	}
}
@Configuration
@EnableWebSocketMessageBroker
class WebSocketConfiguration : WebSocketMessageBrokerConfigurer {

	// ...

	override fun configureMessageBroker(registry: MessageBrokerRegistry) {
		registry.setPathMatcher(AntPathMatcher("."))
		registry.enableStompBrokerRelay("/queue", "/topic")
		registry.setApplicationDestinationPrefixes("/app")
	}
}
<beans xmlns="http://www.springframework.org/schema/beans"
	   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	   xmlns:websocket="http://www.springframework.org/schema/websocket"
	   xsi:schemaLocation="
					http://www.springframework.org/schema/beans
					https://www.springframework.org/schema/beans/spring-beans.xsd
					http://www.springframework.org/schema/websocket
					https://www.springframework.org/schema/websocket/spring-websocket.xsd">

	<websocket:message-broker application-destination-prefix="/app" path-matcher="pathMatcher">
		<websocket:stomp-endpoint path="/stomp"/>
		<websocket:stomp-broker-relay prefix="/topic,/queue" />
	</websocket:message-broker>

	<bean id="pathMatcher" class="org.springframework.util.AntPathMatcher">
		<constructor-arg index="0" value="."/>
	</bean>

</beans>

After that, a controller can use a dot (.) as the separator in @MessageMapping methods, as the following example shows:

  • Java

  • Kotlin

@Controller
@MessageMapping("red")
public class RedController {

	@MessageMapping("blue.{green}")
	public void handleGreen(@DestinationVariable String green) {
		// ...
	}
}
@Controller
@MessageMapping("red")
class RedController {

	@MessageMapping("blue.{green}")
	fun handleGreen(@DestinationVariable green: String) {
		// ...
	}
}

The client can now send a message to /app/red.blue.green123.

In the preceding example, we did not change the prefixes on the “broker relay”, because those depend entirely on the external message broker. See the STOMP documentation pages for the broker you use to see what conventions it supports for the destination header.

The “simple broker”, on the other hand, does rely on the configured PathMatcher, so, if you switch the separator, that change also applies to the broker and the way the broker matches destinations from a message to patterns in subscriptions.