package juegos.example.com.appwfb;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

import com.google.firebase.messaging.RemoteMessage;


    public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        MyFirebaseMessagingService fbb = new MyFirebaseMessagingService();
        fbb.onMessageReceived();
    }
}

package juegos.example.com.appwfb;
import android.util.Log;
import com.google.firebase.messaging.FirebaseMessagingService;
import com.google.firebase.messaging.RemoteMessage;

public class MyFirebaseMessagingService extends FirebaseMessagingService {
    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        Log.e("FIREBASE", remoteMessage.getNotification().getBody());
    }

    public void onMessageReceived() {

    }
}