Strategy Design Pattern

UML design of Strategy Design Pattern

The strategy pattern is a behavioral design pattern that enables selecting an algorithm at runtime — Wikipedia.

The strategy design pattern is a behavioral design pattern that allows an object to change its behavior at runtime by providing its internal algorithms (like Octal, Binary, Hexa in UML design).

Advantage:

• Algorithm independency: An object of Strategy Design allows to change the strategy algorithm in the run time.
• Extensibility: Able to add new algorithm in system without changing the existing code.
• Loosely couple: The strategy pattern promotes loose coupling between the objects and algorithm.

Real Example:

• “Collections.sort(List, comparing_algorithm)” is used the strategy design pattern. Comparing algorithm could be ascending, descending or any custom sorting format.
• Design between Controller and View of MVC framework is Strategy Design pattern.

When to use:

Strategy pattern is used when we have multiple algorithms for a specific task, and the client decides the actual implementation be used at runtime. We define multiple algorithms and let client applications pass the algorithm to be used as a parameter. — Digital Ocean.

Strategy Design Pattern Implementation:

References:

• https://www.digitalocean.com/community/tutorials/strategy-design-pattern-in-java-example-tutorial
• https://blog.bitsrc.io/keep-it-simple-with-the-strategy-design-pattern-c36a14c985e9
• https://refactoring.guru/design-patterns/strategy
• https://www.tutorialspoint.com/design_pattern/strategy_pattern.htm