a background service that handles incoming FCM messages.

MessagingService.java

package co.mobiwise.firebasetraining.service;

import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.media.RingtoneManager;
import android.net.Uri;
import android.support.v4.app.NotificationCompat;
import android.util.Log;

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

import co.mobiwise.firebasetraining.MainActivity;
import co.mobiwise.firebasetraining.R;

public class MessagingService extends FirebaseMessagingService {

    private static final String TAG = "MessagingService";

    @Override
    public void onMessageReceived(RemoteMessage remoteMessage) {
        // Handle data payload of FCM messages.
        handleNotification(remoteMessage);
    }

    private void handleNotification(RemoteMessage remoteMessage) {
        // Create Notification
        Intent intent = new Intent(this, MainActivity.class);
        intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0 /* Request code */, intent,
                PendingIntent.FLAG_ONE_SHOT);

        Uri defaultSoundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this)
                .setSmallIcon(R.mipmap.ic_launcher)
                .setContentTitle(remoteMessage.getNotification().getTitle())
                .setContentText(remoteMessage.getNotification().getBody())
                .setAutoCancel(true)
                .setSound(defaultSoundUri)
                .setContentIntent(pendingIntent);

        NotificationManager notificationManager =
                (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());
    }
}

i'm actually getting some data from sport api , four values : time,date , hometeam,awayteam , i want to post this data to https://fcm.googleapis.com/fcm/send , then retreive the posted data and put it in my notification , is there a good way to do that , thank you .