Design Patterns

Creational Patterns

Creational design patterns are design patterns that deal with object creation mechanisms, trying to create objects in a manner suitable to the situation. The basic form of object creation could result in design problems or added complexity to de design. Creational design patterns solve this problem somehow controlling this object creation.

Creational design patterns are further categorized into Object-creational patterns and Class-creational patterns, where Object-creational patterns deal with Object creation and Class-creational patterns deal with Class-instantiation. In greater details, Object-creational patterns defer part of its object creation to another object, while Class-creational patterns defer its objection creation to subclasses.

Five well-known design patterns that are part of creational patterns are:

• Abstract Factory
• Builder
• Factory
• Prototype
• Singleton

Structural Patterns

Structural design patterns are those that ease the design by identifying a simple way to realize relationship between entities. Structural class-creation patterns use inheritance to compose interfaces. Structural object-patterns define ways to compose objects to obtain new functionality.

Example of structural patterns include:

• Adapter
• Bridge
• Composite
• Decorator
• Extensibility
• Facade
• Proxy

Behavioral Patterns

Behavioral design patterns are design patterns that identify common communication patterns between objects and realize these patterns. These patterns increase flexibility in carrying out this communication.

Examples of this type of design patterns include:

• Chain of Responsibility
• Command
• Interpreter
• Iterator
• Mediator
• Memento
• Observer
• State
• Strategy
• Template
• Visitor

In my next posts I am going to show you how to implement some of the patterns listed above.