MyFirebaseMessagingService.java

package com.google.firebase.example.messaging;

import android.content.Context;
import android.util.Log;

import androidx.annotation.NonNull;
import androidx.work.OneTimeWorkRequest;
import androidx.work.WorkManager;
import androidx.work.Worker;
import androidx.work.WorkerParameters;

import com.google.firebase.messaging.FirebaseMessagingService;
import com.google.firebase.messaging.RemoteMessage;

public class MyFirebaseMessagingService extends FirebaseMessagingService {

    private static final String TAG = "MyFirebaseMsgService";

    // [START receive_message]
    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        // TODO(developer): Handle FCM messages here.
        // Not getting messages here? See why this may be: https://goo.gl/39bRNJ
        Log.d(TAG, "From: " + remoteMessage.getFrom());

        // Check if message contains a data payload.
        if (remoteMessage.getData().size() > 0) {
            Log.d(TAG, "Message data payload: " + remoteMessage.getData());

            if (/* Check if data needs to be processed by long running job */ true) {
                // For long-running tasks (10 seconds or more) use WorkManager.
                scheduleJob();
            } else {
                // Handle message within 10 seconds
                handleNow();
            }

        }

        // Check if message contains a notification payload.
        if (remoteMessage.getNotification() != null) {
            Log.d(TAG, "Message Notification Body: " + remoteMessage.getNotification().getBody());
        }

        // 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.
    }
    // [END receive_message]

    // [START on_new_token]
    /**
     * There are two scenarios when onNewToken is called:
     * 1) When a new token is generated on initial app startup
     * 2) Whenever an existing token is changed
     * Under #2, there are three scenarios when the existing token is changed:
     * A) App is restored to a new device
     * B) User uninstalls/reinstalls the app
     * C) User clears app data
     */
    @Override
    public void onNewToken(@NonNull String token) {
        Log.d(TAG, "Refreshed token: " + token);

        // If you want to send messages to this application instance or
        // manage this apps subscriptions on the server side, send the
        // FCM registration token to your app server.
        sendRegistrationToServer(token);
    }
    // [END on_new_token]

    private void scheduleJob() {
        // [START dispatch_job]
        OneTimeWorkRequest work = new OneTimeWorkRequest.Builder(MyWorker.class)
                .build();
        WorkManager.getInstance(this).beginWith(work).enqueue();
        // [END dispatch_job]
    }

    private void handleNow() {
        Log.d(TAG, "Short lived task is done.");
    }

    private void sendRegistrationToServer(String token) {
        // TODO: Implement this method to send token to your app server.
    }

    public static class MyWorker extends Worker {

        public MyWorker(@NonNull Context context, @NonNull WorkerParameters workerParams) {
            super(context, workerParams);
        }

        @NonNull
        @Override
        public Result doWork() {
            // TODO(developer): add long running task here.
            return Result.success();
        }
    }
}