Support SEDA with Spring Integration `MessageChannel`s

[joshlong]

I love the new BlockingQueueItemWriter<O> and BlockingQueueItemReader<I> implementations, but it occurred to me you'd open even more opportunities for users of Spring Integration if you had a MessageChannelItemWriter and MessageChannelItemReader. Behind the scenes a default direct MessageChannel is a Queue, so the default experience could be very similar to with the BlockingQueue equivalents, but MessageChannels can also lead to Spring Integration IntegrationFlows, to websocvkts with Spring MVC 4's WebSocket support, to durable channels backed by JMS, Kafka, etc., to Spring Security interceptors to trap messages, to integration with Spring Cloud Data Flow as an app. All sorts of possibilities.

[fmbenhassine]

Thank you for your feedback, @joshlong !

Yes, this makes sense and I was planning to add it in the spring-batch-integration module. My goal with the introduction of BlockingQueue reader and writer is to make this architecture style possible and available in the spring-batch-infrastructure module (ie for people who are not using Spring Integration).

[joshlong]

Thank you! I am so thankful for you and this amazing project