MainActivity.java

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Log.d(TAG,"Not there yes");

        try {
            String firebaseDeviceToken  = FirebaseInstanceId.getInstance().getToken();
            Log.d(TAG,firebaseDeviceToken);
        } catch (Exception e) {
            Log.d(TAG,e.getMessage());

        }
        //FirebaseInstanceId.getInstance().getToken()
    }