services:
    _defaults:
        autowire: true
        autoconfigure: true
        public: false
        bind:
          $_buyingStateMachine: '@state_machine.buying'

<?php

namespace Customize\Service;

use Customize\Entity\Master\BuyingStatus;
use Customize\Entity\Buying;
use Customize\Repository\Master\BuyingStatusRepository;
use Eccube\Service\PurchaseFlow\Processor\StockReduceProcessor;
use Eccube\Service\PurchaseFlow\PurchaseContext;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Symfony\Component\Workflow\Event\Event;
use Symfony\Component\Workflow\StateMachine;

class BuyingStateMachine implements EventSubscriberInterface
{
    /**
     * @var StateMachine
     */
    private $machine;

    /**
     * @var BuyingStatusRepository
     */
    private $buyingStatusRepository;
    /**
     * @var StockReduceProcessor
     */
    private $stockReduceProcessor;

    public function __construct(StateMachine $_buyingStateMachine, BuyingStatusRepository $buyingStatusRepository, StockReduceProcessor $stockReduceProcessor)
    {
        $this->machine = $_buyingStateMachine;
        $this->buyingStatusRepository = $buyingStatusRepository;
        $this->stockReduceProcessor = $stockReduceProcessor;
    }

...