Fixes https://github.com/spring-projects/spring-integration-samples/issues/189 Also see http://stackoverflow.com/questions/41403174/how-to-propagate-spring-security-context-in-spring-integration-async-messaging-g * Add Control Bus Java DSL and Annotation configuration sample to the Docs * Mention Spring Security `DelegatingSecurityContextAsyncTaskExecutor` in Docs and add test-case to demonstrate Security Context propagation via `@MessagingGateway` Reflect reality for STOMP Docs Doc Polishing