Design Patterns - Simple Factory Pattern

Purpose

The purpose of the design pattern

SimpleFactory is a simple factory pattern.

It differs from the static factory because it is not static. Therefore, you can have multiple factories, differently parameterised, you can subclass it and you can mock it.

It has some advantages over a Static Factory but a Static Factory closes classes for modification, this technically doesn’t (if you needed to change the Simple Factory, you’d be adjusting the class its being called from).

Examples

Examples of how the design pattern can be used

UML

UML design pattern diagram

Code

Code snippets

Bicycle

Bicycle concrete class.


namespace DesignPatterns\Creational\SimpleFactory;

class Bicycle
{
    public function driveTo(string $destination)
    {
    }
}

SimpleFactory

Defer to the SimpleFactory to return an instance of Bicycle. i.e: container(SimpleFactory)->createBicycle();


namespace DesignPatterns\Creational\SimpleFactory;

class SimpleFactory
{
    public function createBicycle(): Bicycle
    {
        return new Bicycle();
    }
}