This factory method instantiates the collection of course objects by delegating the work to the service layer.

该工厂方法通过将这项工作委托给服务层来实例化课程对象集合。

youdao

This factory method instantiates the collection of course objects by delegating the work to the service layer.

该工厂方法通过将这项工作委托给服务层来实例化课程对象集合。

youdao