??Strategy Design Pattern??

?? Understanding the Strategy Design Pattern through Uber Fare Calculation ??

In software design, flexibility and scalability are key. The Strategy Design Pattern is a perfect example of how to achieve this. Let’s explore how Uber might use this pattern to calculate fares.

What is the Strategy Design Pattern?

It’s a behavioral design pattern that defines a family of algorithms, encapsulates each one, and makes them interchangeable. This allows the algorithm to vary independently from clients that use it.

Key Components:

1. Strategy Interface: A common interface for all algorithms.
2. Concrete Strategies: Classes that implement the strategy interface.
3. Context: Maintains a reference to a strategy object and delegates the execution.

Example: Uber Fare Calculation

Strategy Interface:

public interface FareStrategy {
    double calculateFare(double distance, double time);
}

        

Concrete Strategies:

public class RegularFareStrategy implements FareStrategy {
    public double calculateFare(double distance, double time) {
        return (10 * distance) + (1 * time);
    }
}

public class SurgePricingStrategy implements FareStrategy {
    public double calculateFare(double distance, double time) {
        return (20 * distance) + (2 * time);
    }
}

public class FlatFareStrategy implements FareStrategy {
    public double calculateFare(double distance, double time) {
        return 50;
    }
}

        

Context:

public class UberFareCalculator {
    private FareStrategy fareStrategy;

    public void setFareStrategy(FareStrategy fareStrategy) {
        this.fareStrategy = fareStrategy;
    }

    public double calculateFare(double distance, double time) {
        return fareStrategy.calculateFare(distance, time);
    }
}

        

Client Code:

UberFareCalculator fareCalculator = new UberFareCalculator();

fareCalculator.setFareStrategy(new RegularFareStrategy());
System.out.println("Regular Fare: " + fareCalculator.calculateFare(10, 15));

fareCalculator.setFareStrategy(new SurgePricingStrategy());
System.out.println("Surge Fare: " + fareCalculator.calculateFare(10, 15));

fareCalculator.setFareStrategy(new FlatFareStrategy());
System.out.println("Flat Fare: " + fareCalculator.calculateFare(10, 15));

        

Benefits:

• Flexibility: Easily switch between different fare calculation strategies.
• Scalability: Add new fare calculation methods without modifying existing code.

Understanding and implementing design patterns like the Strategy Pattern can significantly enhance the robustness and maintainability of your code. ??