com/example/exp3/BuildConfig.java
 com.example.exp3.BuildConfig
com/example/exp3/MainActivity.java
 com.example.exp3.MainActivity
 com.example.exp3.MainActivity$1
 com.example.exp3.MainActivity$2
 com.example.exp3.MainActivity$3
 com.example.exp3.MainActivity$4
 com.example.exp3.MainActivity$5