Add auto-clear notification on Cordova FirebaseX plugin

Question

I'm trying to clear automatically a notification I received from the FirebaseX plugin on Ionic after one minute. It means that even if the user doesn't click on it, I want the notification to disappear.

For that I modified the plugins/cordova-plugin-firebasex/src/android/FirebasePlugin.java file where it appears to have the onMessageReceived function.

I know nothing in Java so I tried to add a sleep method before the same content of the clearAllNotifications function as this :

  private void onMessageReceived(final CallbackContext callbackContext) {
    FirebasePlugin.notificationCallbackContext = callbackContext;
    if (FirebasePlugin.notificationStack != null) {
        for (Bundle bundle : FirebasePlugin.notificationStack) {
            FirebasePlugin.sendMessage(bundle, applicationContext);
        }
        FirebasePlugin.notificationStack.clear();
    }

    // I want to wait one minute before it executes the code
    TimeUnit.SECONDS.sleep(60);

    // This code is a copy/paste from the clearAllNotifications function
    cordova.getThreadPool().execute(new Runnable() {
        public void run() {
            try {
                NotificationManager nm = (NotificationManager) applicationContext.getSystemService(Context.NOTIFICATION_SERVICE);
                nm.cancelAll();
                callbackContext.success();
            } catch (Exception e) {
                handleExceptionWithContext(e, callbackContext);
            }
        }
    });

}

But I receive an error when I try to build the app :

platforms/android/app/src/main/java/org/apache/cordova/firebase/FirebasePlugin.java:485: error: unreported exception InterruptedException; must be caught or declared to be thrown TimeUnit.SECONDS.sleep(3);

How could I do to automatically clear a notification after some time ? I've already tried with the Handler method as suggested here but I have a similar error, maybe i'm not importing it well.

Thanks