Symfony2 Doctrine2 postPersist on Associations
===

Is there a way to receive Doctrine lifecycle events in symfony2 for an association field?
http://docs.doctrine-project.org/projects/doctrine-orm/en/2.0.x/reference/events.html#lifecycle-events

for example:

    Entity\User.php...

     /**
     * @ORM\ManyToMany(targetEntity="Group", inversedBy="users", cascade={"persist"})
     * @ORM\JoinTable(name="users_groups",
     *      joinColumns={@ORM\JoinColumn(name="user_id", referencedColumnName="id", onDelete="CASCADE")},
     *      inverseJoinColumns={@ORM\JoinColumn(name="group_id", referencedColumnName="id", onDelete="CASCADE")}
     * )
     */
    protected $groups;

So When I create an event listener for the User Entity
http://symfony.com/doc/current/cookbook/doctrine/event_listeners_subscribers.html

The Listener gets called when a Entity\Group is added to the Entity\User.

***NOTE: The only way I can find of getting this functionality is to create an Entity\UserGroup and monitor that postPersist instead of the Users PostPersist.***

Is that the only way to listen for associations of entities?
