How to add token library to Firebase android library

I have read the Firebase documentation, but Correct me if I'm wrong the way did it.

The Steps That I Understand from the Docs :

1. download Token library for java http://ift.tt/1InMcWD but I dont know how to download this via android studio gradle
2. Generete the token using firebas secret
3. and set as admin to true.

my problem is I don't know how to download the TokenGenerator lib. Please someone help.

I'm using java language developing android app.