The design patterns in this project

As title, do you use any design pattern in this project? Such as factory or strategy patterns.

I don't find any design pattern in this project, but I found some SOLID design principles. They're as follows:

The `ProductController` follows the Single Responsibility Principle.


It seems that `Order`, `Payment` and `Product` classes follow the Interface Segregation Principle.


The `RequiredValidator` class follows the Dependency Inversion Principle.


I'm not sure that these above principles are correct. Please check that.

And I also wonder other design patterns are used in this project.

Once we've confirmed, I think it will be great to add them in this project.