演示设计 设计模式demo-design-creating-type-01单例模式 demo-design-creating-type-02-00工厂模式 demo-design-creating-type-02-01工厂模式 demo-design-creating-type-02-02工厂模式 demo-design-creating-type-03-00抽象工厂模式 demo-design-creating-type-03-01抽象工厂模式 demo-design-creating-typ