A really bad Dependency Injection example

EggProcurementController.php

<?php
namespace Acme\CookieRobot\Controllers;

use Acme\FoodInventory;

class EggProcurementController extends BaseController
{
    /**
     * @type Acme\FoodInventory
     */
    protected $inventory;

    /**
     * Construct a new EggProcurementController
     *
     * @param Acme\FoodInventory $inventory
     */
    public function __construct(FoodInventory $inventory)
    {
        $this->inventory = $inventory;
    }

    /**
     * Procure some amount of eggs
     *
     * @param int $quantity The number of eggs to procure
     *
     * @return Acme\Egg[] An array of eggs
     */
    public function procure($quantity = 2)
    {
        // Silly pseudo-code follows...
        if (!$this->inventory->has(FoodInventory::EGG, $quantity)) {
            throw new InvalidArgumentException(
                "Unable to locate $quantity eggs!"
            );
        }

        $this->moveTo($this->inventory->locationOf(FoodInventory::EGG));
        $eggs = $this->acquire(FoodInventory::EGG, $quantity);
        $this->moveBack();
        return $eggs;
    }
}