Best client/server architecture to develop Facebook application?

I want to develop a Facebook application with Flex 4 technology for client side and Java (Spring based) for server side.

My questions are :

• The best architecture to interact with Facebook plateform is : Facebook AS3 library used directly in my client side, or Facebook Java library (RestFb) in my server side ?
• In general way, to interact with any external plateform (Facebook, Google, etc ...) where the calls must be done (server or client side) ?

Thank you very much,

开发者_运维技巧Anthony

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I'd use servers side solution, because it would give me more control to:

1. filter requests
2. do statistics
3. update server, without updating all clients
4. have one server that supports multiple clients (web/mobile)