"There was nothing you could have done, Luke, had you been there. You'd have been killed too, and the droids would now be in the hands of the Empire."

While the Android SDK comes with a complete set of javadocs, the source code of the SDK is missing in the SDK distribution. This is very unfortunate, since you cannot easily debug into SDK methods (at least not without running into de-compiled code) nor can you see how things actually work.
However, there is a quick fix to that problem. I downloaded the complete Android source including the Linux, drivers, libs, etc., like explained here: http://source.android.com/download and ran my short bash script on the source tree: