Strategy

Usage

• Also known as: Policy
• Encapsulates an algorithm inside a class
• Define a family of algorithms, encapsulate each one, and make them interchangeable
• Let the algorithm vary independently from clients that use it

Diagram

Participants

Strategy

• Declares an interface common to all supported algorithms
• Context uses this interface to call the algorithm defined by a ConcreteStrategy

ConcreteStrategy

• Implements the algorithm using the Strategy interface

Context

• Is configured with a ConcreteStrategy object
• Maintains a reference to a Strategy object
• May define an interface that lets Strategy access its data.