String classToType (Class cls) {
        if (cls == Point.class) {
            return "int2";
        }
        else if (cls == Integer.TYPE
                 || cls == Integer.class) {
            return "int";
        }
        else if (cls == Double.TYPE
                 || cls == Double.class) {
            return "double";
        }
        else if (cls == String.class) {
            return "String";
        }
        else if (cls == Boolean.TYPE
                 || cls == Boolean.class) {
            return "boolean";
        }
        else {
            return null;
        }
    }