title: Symfony2, Doctrine, getDoctrine() without __construct() method
body: <p>We have service as </p>
  
  <pre><code>services:
      service_name:
          class: One\SomeBundle\Controller\OurController
  </code></pre>
  
  <p>What need we add, to make $this->getDoctrine() works in our "OurController" ?
  I tried in "OurController"</p>
  
  <pre><code>$this-&gt;countainer-&gt;get('doctrine') 
  // and
  $this-&gt;getDoctrine()
  </code></pre>
  
  <p>but nothing happens, just errors.</p>
  
  <p>I want that this controller use native methods such as $this->getDoctrine(). As I know we can give arguments to controller(arguments in services.yml), and then apply it, but can we set it as default? Without    </p>
  
  <pre><code>function __construct($em)
  {
      $this-&gt;em = $em;
  }
  </code></pre>
  
  <p>and other additional stuff. All i need is to make $this->getDocrine() works.</p>