testoverwrite,很明显的，就是java语言的类的方法重写。涉及父类的方法被子类的方法重写。重写后的方法跟父类没有任何联系。-testoverwrite, obviously, is the java language class method overrides. The method involves the parent class method subclasses override. Overridden method does not have any contact with the parent class.