设计模式中重要的工厂模式，简单工厂模式是类的创建模式，又名静态工厂方法，是由一个工厂类根据参数来决定创立出哪一种产品类的实例-Important design patterns factory pattern is a simple factory pattern to create a class model, also known as a static factory method, is a factory class to decide according to the paramet