Designing Pattern
- Creational Patterns
- Strucutural Patterns
- Behavioral Patterns
1. Creational Patterns:
Abtaract Factory:
Provide an interface for creating families of related or dependent objects without specifying their concrete classes.
Builder Patterns:
Separate the construction of a complex object from its representation so that the same construction process can create different representations.
Factory Method:
Define an interface for creating an object, but let subclasses decide which class to instantiate. Factory Method lets a class defer instantiation to subclasses.
Prototype Patterns:
Specify the kind of objects to create using a prototypical instance, and create new objects by copying this prototype.
Singleton Patterns:
Ensure a class has only one instance and provide a global point of access to it.
2. Strucutural Patterns
Adapter :
Convert the interface of a class into another interface clients expect. Adapter lets classes work together that couldn't otherwise because of incompatible interfaces.
Bridge :
Decouple an abstraction from its implementation so that the two can vary independently.
Composite:
Compose objects into tree structures to represent part-whole hierarchies. Composite lets clients treat individual objects and compositions of objects uniformly.
Decorate:
Attach additional responsibilities to an object dynamically. Decorators provide a flexible alternative to subclassing for extending functionality.
facade:
Provide a unified interface to a set of interfaces in a subsystem. Façade defines a higher-level interface that makes the subsystem easier to use.
Flyweight:
Use sharing to support large numbers of fine-grained objects efficiently.
Proxy:
Provide a surrogate or placeholder for another object to control access to it.
3.Behavioral Patterns
Chain of Responibility:
Avoid coupling the sender of a request to its receiver by giving more than one object a chance to handle the request. Chain the receiving objects and pass the request along the chain until an object handles it.
Command:
Encapsulate a request as an object, thereby letting you parameterize clients with different requests, queue or log requests, and support undoable operations.
Interpreter:
Given a language, define a representation for its grammar along with an interpreter that uses the representation to interpret sentences in the language.
Iterator:
Provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation.
Mediator:
Define an object that encapsulates how a set of objects interact. Mediator promotes loose coupling by keeping objects from referring to each other explicitly, and it lets you vary their interaction independent.
Memento:
Without violating encapsulation, capture and externalize an object's internal state so that the object can be restored to this state later.
Observe:
Define a one-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically.
State:
Allow an object to alter its behavior when its internal state changes. The object will appear to change its class.
Strategy:
Define a family of algorithms, encapsulate each one, and make them interchangeable. Strategy lets the algorithm vary independently from clients that use it.
Template Method:
Define the skeleton of an algorithm in an operation, deferring some steps to subclasses. Template Method lets subclasses redefine certain steps of an algorithm without changing the algorithm's structure.
Visitor:
Represent an operation to be performed on the elements of an object structure. Visitor lets you define a new operation without changing the classes of the elements on which it operates.
