My application has to recieve notification from Amazon SNS. Howerver, In the tutorial from this, I have to use Google Cloud Messaging to implement. I found that Google encourages developer to migrate from Google Cloud Messaging to Firebase Cloud Messaging, so I decide to choose Firebase Cloud Messaging. The problem is when I push notification from Amazon console to my Application, it throws an Null pointer exception in the last line of code below.

public void onMessageReceived(RemoteMessage remoteMessage) {
    // TODO(developer): Handle FCM messages here.
    // If the application is in the foreground handle both data and notification messages here.
    // Also if you intend on generating your own notifications as a result of a received FCM
    // message, here is where that should be initiated. See sendNotification method below.
    Log.d(TAG, "From: " + remoteMessage.getFrom());//getFrom() method returns right outcome
    Log.d(TAG, "Notification Message Body: " + remoteMessage.getNotification().getBody());
}    

How can I fix it? Thanks