How to determine Android operating system via code [duplicate]

This question already has answers here: Closed 10 years ago.

Possible Duplicate:

How to retrieve the android sdk version?

I'm developing an Android app that needs to provide notifications. For operating systems prior to 2.2 I'm going to use polling, but for new operating systems I want to utilize the new C2DM method. Is there a way to detect which operating system 开发者_JAVA技巧the application is installed on via code? Or is there a better way to go about this altogether?

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Have a look at: http://developer.android.com/reference/android/os/Build.VERSION.html