CyanogenMod Platform SDK
· The Platform SDK provides a set of APIs that give you easy access to a variety of different features within CyanogenMod. The SDK exposes APIs and system level framework access in the Android framework that aren't available in any other distribution.
Download JD-GUI to open JAR file and explore Java source code file (.class .java)
Click menu "File → Open File..." or just drag-and-drop the JAR file in the JD-GUI window platform.sdk-6.0.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.