Design Patterns in PHP 8: Flyweight

Flyweight is a structural design pattern that lets you fit more objects into the available amount of RAM by sharing common parts of state between multiple objects instead of keeping all of the data in each object.

Today, we're going to dive into another fascinating design pattern that can help us write more efficient and scalable PHP code. If you've ever found yourself dealing with a large number of similar objects and wondered how to manage them more efficiently, then you're in for a treat. We're going to explore the Flyweight pattern, a structural design pattern that's all about using memory more efficiently.

The Flyweight pattern is like a master of disguise. It allows us to minimize memory usage by sharing as much data as possible with similar objects. It's like a secret agent who changes a few details about their appearance to take on a new identity, while their core characteristics remain the same. In the context of our PHP code, the Flyweight pattern allows us to handle thousands, or even millions, of objects without breaking a sweat.

In this article, we'll be taking a trip to the world of e-commerce. We'll see how the Flyweight pattern can be used to manage product variations more efficiently, saving memory and improving performance. So, buckle up and let's get started!

For the example, let's consider an e-commerce platform that sells T-shirts. Each T-shirt comes in different sizes and colors, but all T-shirts of the same design share some common attributes like product description, image, and price. The shared data can be moved out into a separate flyweight object, which can be shared among all T-shirt objects.

class TShirtFlyweight
{
 private string $description;
 private string $image;
 private float $price;

 public function __construct(string $description, string $image, float $price)
 {
 $this->description = $description;
 $this->image = $image;
 $this->price = $price;
 }

 // Getters for description, image, and price...
}

In this code,TShirtFlyweightis the Flyweight class that contains the shared state (in this case, the product description, image, and price).

class TShirt
{
 private TShirtFlyweight $flyweight;
 private string $color;
 private string $size;

 public function __construct(TShirtFlyweight $flyweight, string $color, string $size)
 {
 $this->flyweight = $flyweight;
 $this->color = $color;
 $this->size = $size;
 }

 // Getters for color, size, and flyweight...
}

TShirtis the class that contains the unique state (in this case, the color and size of the T-shirt).

class TShirtFactory
{
 private array $flyweights = [];

 public function getFlyweight(string $description, string $image, float $price): TShirtFlyweight
 {
 $key = md5($description . $image . $price);

 if (!isset($this->flyweights[$key])) {
 $this->flyweights[$key] = new TShirtFlyweight($description, $image, $price);
 }

 return $this->flyweights[$key];
 }
}

TShirtFactoryis used to create and manage flyweight objects.

$factory = new TShirtFactory();
$flyweight = $factory->getFlyweight('Cool T-Shirt', 'image.png', 19.99);

$tshirt1 = new TShirt($flyweight, 'red', 'M');
$tshirt2 = new TShirt($flyweight, 'blue', 'L');
$tshirt3 = new TShirt($flyweight, 'green', 'S');

All T-shirts ( $tshirt1 , $tshirt2 , $tshirt3 ) share the same description, image, and price, but have different colors and sizes.

In our e-commerce example, we saw how the Flyweight pattern can be used to manage product variations more efficiently, saving memory and improving performance. It's like having a super-efficient warehouse manager who knows exactly where everything is and can retrieve it in an instant.

We've just taken a deep dive into the world of the Flyweight pattern, exploring how it can help us manage a large number of similar objects more efficiently in PHP. It's like having a secret weapon in our arsenal that allows us to handle thousands, or even millions, of objects without breaking a sweat.

Remember, design patterns like the Flyweight are not one-size-fits-all solutions. They are tools in our developer toolbox, and knowing when and how to use them can make the difference between code that just works and code that works efficiently and elegantly.

I hope you found this exploration of the Flyweight pattern helpful and enlightening. As always, I encourage you to roll up your sleeves, get your hands dirty with some code, and try implementing the Flyweight pattern in your own projects.