Example of the Python design Pattern Adapter Pattern

Python design mode

Three types:

1. Creation type
* Flexible object creation *
-Abstract factory
-Builder
-Factory method
-Prototype
-Singleton
2. Structural
* Convert one object to another, or combine small objects into large objects *
-Adapter
-Bridging
-Combination
-Modifier
-Appearance
-Enjoy RMB
-Proxy
3. Behavior type
* Focus on the process of work, interaction between algorithms and objects *
-Responsibility chain
-Command
-Interpreter
-Iterator
-Intermediary
-Memorandum
-Observer
-Status
-Policy
-Template method
-Visitor

Adapter mode Adapter Pattern

Concept:

It is an interface adaptation technology that allows you to use a class that is incompatible with another interface.
During use, the interfaces of both classes do not need to be modified.
Scenario:

Put a class out of its original application scenario and run it in another environment, and this class cannot be modified.
Example:

Create a person and click it to display the name and talk.

The code is as follows:	Copy code
Class Person (object): "A representation of a person in 2D Land" def init (self, name): self. name = name def make_noise (self): return "hello" Def click_creature (creature): "" React to a click by retrieving the creature's name and what is says "return creature. name, creature. make_noise ()

Create a dog

The code is as follows:	Copy code
Class Dog (object): "A representation of a dog in 2D Land" def init (self, name): self. name = name def bark (self): return "woof"

The dog only has bark and does not have make_noise. It must be adapted.

The code is as follows:

Copy code

The Class Adapter The Object Adapter The Class Adapter From dog import Dog Class Creature (object ): "The base class for creatures in 2D Land """ Def make_noise (self ): """ This is a technique to fake an ABC In Python 2.X """ Raise NotImplementedError Class Person (Creature ): "A representation of a person in 2D Land """ Def _ init _ (self, name ): Self. name = name Def make_noise (self ): Return "hello" Class DogClassAdapter (Creature, Dog ): "Adapts the Dog class through multiple inheritance """ Def _ init _ (self, name ): Dog. _ init _ (self, name) Def make_noise (self ): """ Provide the 'make _ noise 'method that The client expects """ Return self. bark () The Object Adapter Class DogObjectAdapter (Creature ): "Adapts the Dog class through encapsulation """ Def _ init _ (self, canine ): Self. canine = canine Def make_noise (self ): "This is the only method that's adapted """ Return self. canine. bark () Def _ getattr _ (self, attr ): "Everything else is delegated to the object """ Return getattr (self. canine, attr) * Simple * From dog import Dog Class Person (object ): "A representation of a person in 2D Land """ Def _ init _ (self, name ): Self. name = name Def make_noise (self ): Return "hello" Class DogAdapter (object ): "Adapts the Dog class through encapsulation """ Def _ init _ (self, canine ): Self. canine = canine Def make_noise (self ): "This is the only method that's adapted """ Return self. canine. bark () Def _ getattr _ (self, attr ): "Everything else is delegated to the object """ Return getattr (self. canine, attr) Def click_creature (creature ): """ React to a click by showing the creature's Name and what is says """ Return (creature. name, creature. make_noise ()) Test From dog import Dog From listing3 import Person, DogAdapter Def exercise_system (): Person = Person ("Bob ") Canine = DogAdapter (Dog ("Fido ")) For critter in (person, canine ): Print critter. name, "says", critter. make_noise () If _ name _ = "_ main __": Exercise_system ()

Create more creatures, cats, birds...
####

The code is as follows:

Copy code

Class Cat (object ): "A representation of a cat in 2D Land """ Def _ init _ (self, name ): Self. name = name Def meow (self ): Return "meow" Class CreatureAdapter (object ): "Adapts a creature for clients in 2D Land """ Def _ init _ (self, creature, make_noise ): "Pass in the function to use as 'Make _ noise '""" Self. creature = creature Self. make_noise = make_noise Def _ getattr _ (self, attr ): "Everything else is delegated to the object """ Return getattr (self. creature, attr)

Test

The code is as follows:	Copy code
From dog import Dog From cat import Cat From twodeeland import Person, CreatureAdapter Def exercise_system (): Person = Person ("Bob ") Fido = Dog ("Fido ") Canine = CreatureAdapter (fido, fido. bark) Whiskers = Cat ("Whiskers ") Feline = CreatureAdapter (whiskers, whiskers. meow) For critter in (person, canine, feline ): Print critter. name, "says", critter. make_noise