Simple Broker

The built-in simple message broker handles subscription requests from clients, stores them in memory, and broadcasts messages to connected clients that have matching destinations. The broker supports path-like destinations, including subscriptions to Ant-style destination patterns.

Applications can also use dot-separated (rather than slash-separated) destinations. See Dots as Separators.

If configured with a task scheduler, the simple broker supports STOMP heartbeats. To configure a scheduler, you can declare your own TaskScheduler bean and set it through the MessageBrokerRegistry. Alternatively, you can use the one that is automatically declared in the built-in WebSocket configuration, however, you’ll need @Lazy to avoid a cycle between the built-in WebSocket configuration and your WebSocketMessageBrokerConfigurer. For example:

Java
Kotlin

@Configuration
@EnableWebSocketMessageBroker
public class WebSocketConfiguration implements WebSocketMessageBrokerConfigurer {

	private TaskScheduler messageBrokerTaskScheduler;

	@Autowired
	public void setMessageBrokerTaskScheduler(@Lazy TaskScheduler taskScheduler) {
		this.messageBrokerTaskScheduler = taskScheduler;
	}

	@Override
	public void configureMessageBroker(MessageBrokerRegistry registry) {
		registry.enableSimpleBroker("/queue/", "/topic/")
				.setHeartbeatValue(new long[] {10000, 20000})
				.setTaskScheduler(this.messageBrokerTaskScheduler);

		// ...
	}
}

@Configuration
@EnableWebSocketMessageBroker
class WebSocketConfiguration : WebSocketMessageBrokerConfigurer {

	private lateinit var messageBrokerTaskScheduler: TaskScheduler

	@Autowired
	fun setMessageBrokerTaskScheduler(@Lazy taskScheduler: TaskScheduler) {
		this.messageBrokerTaskScheduler = taskScheduler
	}

	override fun configureMessageBroker(registry: MessageBrokerRegistry) {
		registry.enableSimpleBroker("/queue/", "/topic/")
			.setHeartbeatValue(longArrayOf(10000, 20000))
			.setTaskScheduler(messageBrokerTaskScheduler)

		// ...
	}
}