Design Patterns and Design Principles with their best practices and description

Define a family of algorithms, encapsulate each one, and make them interchangeable. Strategy lets the algorithm vary independently from the clients that use it.

• family
• interchangable
• vary independenty

Define an interface for creating an object, but let subclasses decide which class to instantiate. Factory Method lets a class defer instantiation to subclasses.

• family
• interchangable
• vary independenty

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.

• represent an Operation
• Performed on an
• Elements of object
• in a Structure

Compose objects into tree structures to represent whole-part hierarchies. Composite lets clients treat individual objects and compositions of objects uniformly.

• Compose
• Tree structure
• represent Part-whole hierarchies
• Treat individual objects and compositions

Provide a way to access the elements of an aggregate object sequentially without exposing its underlying representation.

• access Element
• Aggregate object
• Squencially
• wihtout Exposing

Provide a surrogate or placeholder for another object to control access to it.

• Surrogate
• Placeholder
• control Access

• from Derek Banas - THE BEST!

• Strategy vs State

• Proxy vs Decorator vs Adapter vs Facade

• Decorator vs Adapter

• Beautifully put statement from SO