How to write "Intercepting Filter Pattern" like Java's servlet filter in Flex?

I want to know how to write "Intercepting Filter Pattern" like Java's servlet filter in Flex.

And I want to insert it into the classes which have a role of server communicating.

Please show me any s开发者_StackOverflowample codes if any...

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Create a class which will play a role of connector between your program and server. Put there event listener for server events. Create a constant types for different types of events that server could send to your program. Put a switch into event listener that receive these events, and re dispatch them to the specific places, depending on which type of the event it was.