Strategy Design Pattern

The Strategy Design Pattern is a behavioral design pattern that allows for selecting an algorithm's behavior at runtime. It involves defining a family of algorithms, encapsulating each in its own class, and making them interchangeable. The pattern consists of a context class, strategy interface, and concrete strategies. The context class maintains a reference to a strategy object and interacts with it through a common interface. The strategy interface defines a common interface for all concrete strategies, which implement the strategy interface with specific algorithms. The pattern is beneficial when multiple algorithms or behaviors need to be defined within a single class, or when the behavior of a class needs to change dynamically based on user input or other runtime conditions. It promotes flexibility, extensibility, readability, and maintenance, adhering to the Open/Closed Principle. However, it can introduce additional complexity and overhead if not used judiciously. Examples of its use include sorting algorithms, discount calculation, and authentication mechanisms.