Event subscription for EntityTypeEvents So I'm trying to get an event subscriber working for EntityTypeEvents and I can't figure out why it's not firing.

This is a general outline of the code:

namespace Drupal\subscriber_class_module;

use Symfony\Component\EventDispatcher\EventSubscriberInterface;
use Drupal\Core\Entity\EntityTypeEvents;
use Drupal\Core\Entity\EntityTypeEvent;

class SubscriberClassModuleSubscribesToEntityTypeEvents implements EventSubscriberInterface {

    public function onCreate(EntityTypeEvent $event)  {
          //Do things on creation
    }
    public function onUpdate(EntityTypeEvent $event)  {
          //Do things on update
    }
    public function onDelete(EntityTypeEvent $event)  {
          //Do things on delete
    }
    static function getSubscribedEvents() {
         $events = [];

         $events[EntityTypeEvents::CREATE][] = array('onCreate', 100);
         $events[EntityTypeEvents::UPDATE][] = array('onUpdate', 100);
         $events[EntityTypeEvents::DELETE][] = array('onDelete', 100);
         return $events;
    }
}


Added class declaration and namespacing.  I should note that the same class that I am using has no probablem firing on kernel events, I'm just wondering if there is something special about entity events.
i already have the same issue, you have to implement this class to EntityTypeListenerInterface and use the trait EntityTypeEventSubscriberTrait 

class SubscriberClassModuleSubscribesToEntityTypeEvents implements EntityTypeListenerInterface, EventSubscriberInterface{

use EntityTypeEventSubscriberTrait;

public function __construct(EntityManagerInterface $entity_manager) {
    $this-&gt;entityManager = $entity_manager;
}

public function onCreate(EntityTypeEvent $event)  {
      //Do things on creation
}
public function onUpdate(EntityTypeEvent $event)  {
      //Do things on update
}
public function onDelete(EntityTypeEvent $event)  {
      //Do things on delete
}

/**
 * {@inheritdoc}
 */
public static function getSubscribedEvents() {
    return static::getEntityTypeEvents();
}


}

and you get to load entity manager in your module.service.yml declaration
    arguments: ['@entity.manager']