Asynchronous Observer Pattern.

Question

Hi guys,

I wanted to find out other ways to do Asynchronous Observer Pattern without using Message Queue. Ideas and examples are mostly welcomed. :-) (Think of this as a brainstorming session).

PS Language preference is up to you.

Answer 1

In Java, you could submit notification tasks to an Executor which manages a single thread of group of threads that are all responsible just for handling observable events. You still effectively have a queue, but instead of a "message queue" in the traditional sense it's a queue of notification tasks.

Answer 2

In .NET you can use the Reactive Framework.

Answer 3

In Erlang this is built-in in the language and is the only way to communicate between processes. Just use the send primitive: Pid ! Message

Using asynchronous message-passing, you will always use some kind of message queue internally, otherwise they wouldn't be asynchronous.