Correct way to update a Set containing widgets Ids in SharedPreferences.

gistfile1.txt

public static void updateSetInPreferences(Context context, int appWidgetId, String key, String action)
    {
        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
        SharedPreferences.Editor editor = prefs.edit();
        Set<String> storedSet, in;
        switch(action)
        {
            case ACTION_ADD_APP_WIDGET_ID:
                storedSet = prefs.getStringSet(key, new HashSet<>());
                in = new HashSet<>(storedSet);
                in.add(String.valueOf(appWidgetId));
                editor.putStringSet(key, in);
                break;

            case ACTION_REMOVE_APP_WIDGET_ID:
                storedSet = prefs.getStringSet(key, new HashSet<>()); // Access it
                in = new HashSet<>(storedSet);
                in.remove(String.valueOf(appWidgetId));
                editor.putStringSet(key, in); // Put it back in Prefs
                break;
        }
        editor.apply();
    }