Is there an out-of-the-box thread pool with multiple queues (that ensure serial processing of each queue)?

Question

Among all my tasks, I have some that must be processed serially (they can never run concurrently and they must be processed in order).

I achieved that creating a sep

Answer 1

Akka, as suggested by @SotiriosDelimanolis and @AlexeiKaigorodov seems promising, as well as @Dodd10x second answer, which certainly solves the problem. The only downside is that I'd have to code my own polling strategy to make sure my tasks are eventually added to the executor (like the infinite loop in his example).

On the other hand, the Striped Executor Service suggested by @OldCurmudgeon exactly matches my problem and works out of the box simply as a custom ExecutorService.

This magical thread pool would ensure that all Runnables with the same stripeClass would be executed in the order they were submitted, but StripedRunners with different stripedClasses could still execute independently. He wanted to use a relatively small thread pool to service a large number of Java NIO clients, but in such a way that the runnables would still be executed in-order.

There is even a comment about using a single threaded thread pool for each group (stripe), as it was suggested here:

Several suggestions were made, such as having a SingleThreadExecutor for each stripeClass. However, that would not satisfy the requirement that we could share the threads between connections.

I see this as the best solution for its simplicity and ease of use.