Display a tree hierarchy - symfony

Question

I have a Category entity designed to represent a Forum category. I used StofDoctrineExtensionsBundle in order to use its Tree annotation, in order to have a hierarchy in categories. Now, I would like to represent that hierarchy in a string, some like Category/Subcategory/Subsubcategory/Foo. How can I get all the hierarchy in an unique request with Doctrine ?
// Category.php
use Doctrine\Common\Collections\ArrayCollection;
use Gedmo\Mapping\Annotation as Gedmo;
use Doctrine\ORM\Mapping as ORM;
/**
* #Gedmo\Tree(type="nested")
* #ORM\Table()
* #ORM\Entity(repositoryClass="PC\ForumBundle\Entity\Repository\CategoryRepository")
*/
class Category
{
/**
* #ORM\Column(type="integer")
* #ORM\Id
* #ORM\GeneratedValue
*/
private $id;
/**
* #ORM\Column(length=64)
*/
private $title;
/**
* #ORM\Column(type="text", nullable=true)
*/
private $description;
/**
* #Gedmo\Slug(fields={"title"})
* #ORM\Column(length=64, unique=true)
*/
private $slug;
/**
* #Gedmo\TreeLeft
* #ORM\Column(type="integer")
*/
private $lft;
/**
* #Gedmo\TreeRight
* #ORM\Column(type="integer")
*/
private $rgt;
/**
* #Gedmo\TreeParent
* #ORM\ManyToOne(targetEntity="Category", inversedBy="children")
* #ORM\JoinColumn(name="parent_id", referencedColumnName="id", onDelete="CASCADE")
*/
private $parent;
/**
* #Gedmo\TreeRoot
* #ORM\Column(type="integer", nullable=true)
*/
private $root;
/**
* #Gedmo\TreeLevel
* #ORM\Column(name="lvl", type="integer")
*/
private $level;
/**
* #ORM\OneToMany(targetEntity="Category", mappedBy="parent")
*/
private $children;
// ...

Answer 1

In complement of palra answer
The repository code :
namespace Foo\MyBundle\Entity;
use Doctrine\ORM\EntityRepository;
use Gedmo\Tree\Entity\Repository\NestedTreeRepository;
class CategoryRepository extends NestedTreeRepository
{
}
A Twig code example (bootstrap) :
<ol class="breadcrumb">
<li><i class="fa fa-home"></i></li>
{% for p in path %}
<li><a {% if loop.last %}class="active"{% endif %}
href="{{ path(...) }}">{{ p.name }}</i></a></li>
{% endfor %}
</ol>

Answer 2

I finally found how to do it :
Make your repository class extend Gedmo\Tree\Entity\Repository\NestedTreeRepository
Call the method getPath($node) on it.
Example :
// Assuming $category is provided by a ParamConverter
public function indexAction(Category $category = null)
{
return array(
'category' => $category,
'path' => $this->repo->getPath($category)
);
}