Cocoa - Is there a way to check on whether not a cache exists for a NSURLConnection?

I would like to be able to log monitor/log when a local machine cache i开发者_如何学Cs being used or when the data is being drawn from the remote source.

is there a NSURLConnection.cacheExists method? Or better still one that shows the expiration date or other cache details?

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You can ask the shared NSURLCache object for a cached response for a request.