Python: Common Design Patterns

Python: Common Design Patterns

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  Common Design Patterns DamianGordon
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  Common Design Patterns •Iterator • Decorator • Observer • Strategy • State • Singleton • Template • Adapter • Façade • Flyweight • Command • Abstract Factory • Composite
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  Iterator Pattern • Theiterator pattern is a design pattern in which an iterator is used to traverse a container and access the container's elements.
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  Decorator Decorator Pattern • Thedecorator pattern is a design pattern which wraps an existing class and can alter the functionality of the methods. Existing Class
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  Observer Pattern • Theobserver pattern is a design pattern which monitors a core class and different observers react different to changes in the core class. Existing Class Observer 1 Observer 2
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  Strategy Pattern • Thestrategy pattern is a design pattern which presents different potential solutions to the same problem, and allows the program to choose the most suitable one. Solution 1 Solution 3Solution 2 Abstraction
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  State Pattern • Thestate pattern is a design pattern which represents a system that goes through different states, and records the current state and the transitions between states. State 1 State 3State 2 Current State Manager (or Context)
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  Singleton Pattern • Thesingleton pattern is a design pattern which allows only one object based on a certain class to exist. One Object
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  Template Pattern • Thetemplate pattern is a design pattern which creates a common base class the can be inherited by multiple class that share common states, these can override the base class methods. Base Case: Step1() Step2() Step3() Case1: Step2() Case2: Step3()
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  Adapter Pattern • Theadapter pattern is a design pattern which allows two pre- existing objects to interact with each other, even if their interfaces are not compatible. Interface 1 Interface2 Adapter
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  Façade Pattern • Thefaçade pattern is a design pattern which presents a simple interface to complex system but encapsulating typical usage into a new object. Façade BIG SYSTEM
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  Flyweight Pattern • Theflyweight pattern is a design pattern which helps objects that share the same state to use the same memory location. Flyweight Current State
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  Command Pattern • Thecommand pattern is a design pattern which creates an object (an execute object) that can execute another object at a later time. Existing ClassRun 2 hours from now Execute Object
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  Abstract Factory Pattern •The abstract factory pattern is a design pattern which returns a different class (or implementation) of the same system, depending on the platform, local settings, or current locale. Solution 1 Solution 3Solution 2 Abstract Factory
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  Composite Pattern • Thecomposite pattern is a design pattern which allows complex tree-like structures to be built easily from simple components. Composite Composite CompositeCompositeLeaf CompositeLeaf LeafLeaf Leaf
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  etc.