Mastering Python Design Patterns - Second Edition

Real-world examples

An example of the factory method pattern used in reality is in the context of a plastic toy construction kit. The molding material used to construct plastic toys is the same, but different toys (different figures or shapes) can be produced using the right plastic molds. This is like having a factory method in which the input is the name of the toy that we want (for example, duck or car) and the output (after the molding) is the plastic toy that was requested.

In the software world, the Django web framework uses the factory method pattern for creating the fields of a web form. The forms module, included in Django, supports the creation of different kinds of fields (for example, CharField, EmailField, and so on). And parts ...