PHP Design Patterns: Command Pattern

php_design_patterns _command_pattern.php

<?php

// Command
interface Order {
    public function execute();
}

// Receiver Class
class Stock {
    
    private $name = "ABC";
    private $quantity = 10;

    public function buy() {
        echo "Stock [Name: $this->name, Quantity: $this->quantity] bought\n";
    }

    public function sell() {
        echo "Stock [Name: $this->name, Quantity: $this->quantity] sold\n";
    }
    
}

class BuyStock implements Order {

    private $abcStock;

    public function BuyStock(Stock $abcStock){
        $this->abcStock = $abcStock;
    }

    public function execute() {
        $this->abcStock->buy();
    }
    
}

class SellStock implements Order {
    
    private $abcStock;

    public function SellStock(Stock $abcStock){
        $this->abcStock = $abcStock;
    }

    public function execute() {
        $this->abcStock->sell();
    }
    
}

class Broker {

    private $orderList = array();

    public function takeOrder(Order $order) {
        array_push($this->orderList, $order);
    }

    public function placeOrders() {
        foreach($this->orderList as $order) {
            $order->execute();
        }
        unset($orderList);
    }
    
}

// Invoker
$stock = new Stock();
$buyStock = new BuyStock($stock);
$sellStock = new SellStock($stock);
$broker = new Broker();
$broker->takeOrder($buyStock);
$broker->takeOrder($sellStock);
$broker->placeOrders();