Simple Factory

simple-factory.md

Programmatic Example

First of all we have a door interface and the implementation

interface Door {
    public function getWidth() : float;
    public function getHeight() : float;
}

class WoodenDoor implements Door {
    protected $width;
    protected $height;

    public function __construct(float $width, float $height) {
        $this->width = $width;
        $this->height = $height;
    }
    
    public function getWidth() : float {
        return $this->width;
    }
    
    public function getHeight() : float {
        return $this->height;
    }
}

Then we have our door factory that makes the door and returns it

class DoorFactory {
   public static function makeDoor($width, $height) : Door {
       return new WoodenDoor($width, $height);
   }
}

And then it can be used as

$door = DoorFactory::makeDoor(100, 200);
echo 'Width: ' . $door->getWidth();
echo 'Height: ' . $door->getHeight();

When to Use?

When creating an object is not just a few assignments and involves some logic, it makes sense to put it in a dedicated factory instead of repeating the same code everywhere.