AdminController.php

<?php

namespace JStout\MainBundle\Controller;

use Symfony\Bundle\FrameworkBundle\Controller\Controller,
    Sensio\Bundle\FrameworkExtraBundle\Configuration as Extra,
    Symfony\Component\HttpKernel\Exception\NotFoundHttpException,
    JStout\MainBundle\Entity,
    JStout\MainBundle\Form;

/**
* @Extra\Route("/admin")
* @Extra\Template()
*/
class AdminController extends Controller
{
    /**
     * @Extra\Route(name="admin_index")
     * @Extra\Template()
     */
    public function indexAction()
    {
        return array();
    }

    /**
     * @Extra\Route("/advertiser", name="admin_advertiser")
     * @Extra\Route("/advertiser/{id}/edit", name="admin_advertiser_edit")
     * @Extra\Template()
     */
    public function advertiserAction($id = null)
    {
        $advertiser = $this->_getObject('Advertiser', $id);

        $form = $this->get('form.factory')->create(new Form\AdvertiserType(), $advertiser);
        $formHandler = $this->get('form.handler')->create(new Form\AdvertiserHandler(), $form);

        // process form
        if ($formHandler->process()) {
            $this->get('session')->setFlash('notice', 'Successfully ' . (!$this->_isEdit($advertiser) ? 'added' : 'edited') . ' advertiser!');
            return $this->redirect($this->generateUrl('admin_advertiser'));
        }

        return array(
            'form' => $form->createView(),
            'advertisers' => $this->_paginate('Advertiser'),
            'new' => !$this->_isEdit($advertiser)
        );
    }

    [.... a lot of other methods go here ....]

    /**
     * Helper function to allow ability to handle two routes for one controller.
     * This creates a new entity instance or returns the requested $id of the Entity
     *
     * @param  $entityName
     * @param null $id
     * @return Entity Object or NotFoundHttpException
     */
    protected function _getObject($entityName, $id = null)
    {
        // Find object
        if (null !== $id) {
            if (!$object = $this->get('doctrine')->getEntityManager()->find('JStoutMainBundle:' . $entityName, $id)) {
                throw new NotFoundHttpException('The page you requested does not exist!');
            }

            return $object;
        }

        // Initialize new object
        $entityName = 'JStout\MainBundle\Entity\\' . $entityName;
        if (class_exists($entityName)) {
            return new $entityName();
        }

        throw new NotFoundHttpException($entityName . ' was not able to be created.');
    }
}

routing.yml

default:
    resource: "@JStoutMainBundle/Controller/DefaultController.php"
    type:     annotation

admin:
    resource: "@JStoutMainBundle/Controller/AdminController.php"
    type:     annotation