php__symfony__book/src/Controller/ArticleController.php

<?php

namespace App\Controller;

use Symfony\Component\Routing\Annotation\Route;

class ArticleController {

  /**
   * @param $_locale
   * @param $year
   * @param $slug
   *
   * @Route(
   *   path = "/articles/{_locale}/{year}/{slug}.{_format}",
   *   name = "article_show",
   *   defaults = {
   *     "_format": "html",
   *   },
   *   requirements = {
   *     "_locale": "en|fr",
   *     "_format": "html|rss",
   *     "year": "\d+"
   *   }
   *
   * )
   *
   * - placeholders cannot be more than 32 characters long
   * - Special placeholders:
   *   - _format is a special parameter used for the request format and content
   *     type negotiation
   *   - _controller defines the controller for the route as a PHP callable,
   *      including class names if they implement __invoke(); or the service
   *      notation service:method.
   *   - _fragment is the URI fragment (not sent by user agents over HTTP)
   *   - _locale is used to set the locale on the request
   */
  public function show($_locale, $year, $slug) {

  }

}