public static function addById($recipeId)
 {
     if (!isset($_SESSION['cocktailsFavorites'])) {
         $_SESSION['cocktailsFavorites'] = array();
     }
     if (isset($_SESSION['cocktailsFavorites'][$recipeId])) {
         return false;
     }
     $favorite = new Favorite(RecipeDAO::getById($recipeId));
     $_SESSION['cocktailsFavorites'][$recipeId] = $favorite;
     if (isset($_SESSION['cocktailsUser'])) {
         $favorite->setUser($_SESSION['cocktailsUser']);
         self::create($favorite);
     }
 }