Android Studio Doesn't See Some .java Files That Are Present In The Sdk Directory

I built a custom Android ROM that supports A2DP Sink and AVRCP bluetooth profiles which are disabled by default. Now i want to build an app that exploits these profiles, i found th

Solution 1:

The files I need aren't included in the android.jar I have to build an SDK that includes them.

Solution 2:

You can get access to modified android.jar that will allow you to use hidden apis: https://github.com/anggrayudi/android-hidden-api