或者说，抽象类的正确使用是什么？

Or rather, what's the proper use of abstract classes?

youdao

具有非抽象方法的抽象类，如果一个新的抽象类的对象不能被创建的点是什么？

What is the point of having non abstract methods in the abstract class if a new object of the abstract class can't be created?

youdao

接口和抽象类的区别是什么？

What's the difference between an interface and abstract class?

youdao