title: Symfony: The class * was not found in the chain configured namespaces UsersBundle\Entity, FOS\UserBundle\Model
body: <p>I try to follow this tutorial for the pagination: <a href="https://knpuniversity.com/screencast/symfony-rest3/pagerfanta-pagination" rel="nofollow noreferrer">https://knpuniversity.com/screencast/symfony-rest3/pagerfanta-pagination</a></p>
  
  <p>For the moment I have installed the <code>white-october/pagerfanta-bundle</code>, and when I made my user repository as following :</p>
  
  <pre><code>&lt;?php
  // src/UsersBundle/Repository/UserRepository.php
  namespace UsersBundle\Repository;
  
  
  use Doctrine\ORM\EntityRepository;
  
  class UserRepository extends EntityRepository {
  
      public function findAllQueryBuilder() {
          return $this-&gt;createQueryBuilder('user');
      }
  
  }
  </code></pre>
  
  <p>and in my controller action I did this:</p>
  
  <pre><code>&lt;?php
  // src/UsersBundle/Controller/UsersController.php
  
  namespace UsersBundle\Controller;
  
  // use statements ...
  
  /**
   * Class UsersController
   *
   * @package UsersBundle\Controller
   *
   * @Rest\RouteResource("user", pluralize=false)
   * @Rest\NamePrefix( "api_v1_" )
   */
  class UsersController extends FOSRestController implements ClassResourceInterface {
  
      // ...
  
      /**
       * Responsible to list all the registered users.
       *
       * @Rest\QueryParam(name="page", default="1", requirements="\d+",nullable=true)
       *
       * @return array|\Traversable
       */
      public function getListAction( ParamFetcher $param_fetcher ) {
          if ( ! $this-&gt;isGranted( 'ROLE_ADMIN' ) ) {
              throw new UnauthorizedHttpException( 'You do not have sufficient permission to access this resource' );
          }
  
          $qb = $this-&gt;getDoctrine()
              -&gt;getRepository('UsersBundle\Repository\UserRepository')
              -&gt;findAllQueryBuilder();
  
          $adapter = new DoctrineORMAdapter( $qb );
  
          $users = $this-&gt;user_manager-&gt;findUsers();
  
          return $users;
      }
  
      // ...
  
  }
  </code></pre>
  
  <p>I got this output:</p>
  
  <p><code>{"code":500,"message":"The class 'UsersBundle\\Repository\\UserRepository' was not found in the chain configured namespaces UsersBundle\\Entity, FOS\\UserBundle\\Model"}</code></p>
  
  <p>Anyone knows what that output means? Unfortunately I am totally new to Symfony, and I cannot understand what is the issue for this output.</p>