What are the best practices for implementing the factory pattern?

What are the best practices for implementing the factory pattern?

The factory pattern is a creational design pattern that provides an interface for creating objects. Best practices include: 1. Use a factory method to encapsulate object creation. 2. Keep the factory class separate from the product classes. 3. Favor composition over inheritance. 4. Ensure the factory can be extended easily.

Can you give an example of how to implement it?

Sure! Here's a simple example in Python:

class Car:
    def drive(self):
        return "Driving a car"

class Truck:
    def drive(self):
        return "Driving a truck"

class VehicleFactory:
    @staticmethod
    def create_vehicle(vehicle_type):
        if vehicle_type == 'car':
            return Car()
        elif vehicle_type == 'truck':
            return Truck()
        else:
            raise ValueError('Unknown vehicle type')

# Usage
vehicle = VehicleFactory.create_vehicle('car')
print(vehicle.drive())  # Output: Driving a car

What are the advantages of using the factory pattern?

The factory pattern provides several advantages: 1. It promotes loose coupling by separating the creation of objects from their usage. 2. It enhances code maintainability and readability. 3. It allows for easier testing and mocking of objects. 4. It supports the Open/Closed Principle, making it easier to add new types of products.

Are there any common pitfalls to avoid?

Yes, some common pitfalls include: 1. Overcomplicating the factory with too many parameters. 2. Creating a factory that does too much, violating the Single Responsibility Principle. 3. Not considering the lifecycle of the created objects, which can lead to resource leaks.