public String getMaterial() {
        switch (material) {
            case MAPLE:
                return "material was selected: " + material + ", ";
            case OAK:
                return "material was selected: " + material + ", ";
            case POPLAR:
                return "material was selected: " + material + ", ";
            case LINDEN:
                return "material was selected: " + material + ", ";
            default:
                return "selected the wrong material";
        }
    }