The customer class can be an abstract base class for a family of different customer types, such as private or business customer.

客户类可以是用于许多不同客户类型的抽象基类，比如说私有客户或业务客户。

youdao

The customer class can be an abstract base class for a family of different customer types, such as private or business customer.

客户类可以是用于许多不同客户类型的抽象基类，比如说私有客户或业务客户。

youdao