This version is still in development and is not considered stable yet. For the latest stable version, please use Spring Integration 6.2.4!

Process Manager Enterprise Integration Pattern

Enterprise integration patterns include the process manager pattern. You can now easily implement this pattern by using custom process manager logic encapsulated in a RoutingSlipRouteStrategy within the routing slip. In addition to a bean name, the RoutingSlipRouteStrategy can return any MessageChannel object, and there is no requirement that this MessageChannel instance be a bean in the application context. This way, we can provide powerful dynamic routing logic when there is no way to predict which channel should be used. A MessageChannel can be created within the RoutingSlipRouteStrategy and returned. A FixedSubscriberChannel with an associated MessageHandler implementation is a good combination for such cases. For example, you can route to a Reactive Streams, as the following example shows:

@Bean
public PollableChannel resultsChannel() {
    return new QueueChannel();
}
@Bean
public RoutingSlipRouteStrategy routeStrategy() {
    return (requestMessage, reply) -> requestMessage.getPayload() instanceof String
            ? new FixedSubscriberChannel(m ->
            Mono.just((String) m.getPayload())
                    .map(String::toUpperCase)
                    .subscribe(v -> messagingTemplate().convertAndSend(resultsChannel(), v)))
            : new FixedSubscriberChannel(m ->
            Mono.just((Integer) m.getPayload())
                    .map(v -> v * 2)
                    .subscribe(v -> messagingTemplate().convertAndSend(resultsChannel(), v)));
}