Expanded class hierarchy of Item

class \Drupal\Core\Entity\Entity implements \IteratorAggregate, EntityInterface
- class \Drupal\contact\Plugin\Core\Entity\Message implements MessageInterface
- class \Drupal\Core\Config\Entity\ConfigEntityBase implements ConfigEntityInterface
- class \Drupal\Core\Entity\EntityNG
  - class \Drupal\aggregator\Plugin\Core\Entity\Feed implements FeedInterface
  - class \Drupal\aggregator\Plugin\Core\Entity\Item implements ItemInterface
  - class \Drupal\comment\Plugin\Core\Entity\Comment implements CommentInterface
  - class \Drupal\custom_block\Plugin\Core\Entity\CustomBlock implements CustomBlockInterface
  - class \Drupal\entity_test\Plugin\Core\Entity\EntityTest
  - class \Drupal\node\Plugin\Core\Entity\Node implements NodeInterface
  - class \Drupal\taxonomy\Plugin\Core\Entity\Term implements TermInterface
  - class \Drupal\user\Plugin\Core\Entity\User implements UserInterface
- class \Drupal\entity_cache_test_dependency\Plugin\Core\Entity\EntityCacheTest
- class \Drupal\field_test\Plugin\Core\Entity\TestEntity
- class \Drupal\field_ui_test\Plugin\Core\Entity\FieldUITestNoBundle
- class \Drupal\file\Plugin\Core\Entity\File implements FileInterface
- class \Drupal\menu_link\Plugin\Core\Entity\MenuLink implements \Drupal\menu_link\Plugin\Core\Entity\ArrayAccess, MenuLinkInterface