class RecursiveValidator

class RecursiveValidator implements ValidatorInterface {
    
    /**
     * @var \Symfony\Component\Validator\Context\ExecutionContextFactoryInterface
     */
    protected $contextFactory;
    
    /**
     * @var \Symfony\Component\Validator\ConstraintValidatorFactoryInterface
     */
    protected $constraintValidatorFactory;
    
    /**
     * @var \Drupal\Core\TypedData\TypedDataManager
     */
    protected $typedDataManager;
    
    /**
     * Creates a new validator.
     *
     * @param \Symfony\Component\Validator\Context\ExecutionContextFactoryInterface $context_factory
     *   The factory for creating new contexts.
     * @param \Symfony\Component\Validator\ConstraintValidatorFactoryInterface $validator_factory
     *   The constraint validator factory.
     * @param \Drupal\Core\TypedData\TypedDataManagerInterface $typed_data_manager
     *   The typed data manager.
     */
    public function __construct(ExecutionContextFactoryInterface $context_factory, ConstraintValidatorFactoryInterface $validator_factory, TypedDataManagerInterface $typed_data_manager) {
        $this->contextFactory = $context_factory;
        $this->constraintValidatorFactory = $validator_factory;
        $this->typedDataManager = $typed_data_manager;
    }
    
    /**
     * {@inheritdoc}
     */
    public function startContext($root = NULL) : ContextualValidatorInterface {
        return new RecursiveContextualValidator($this->contextFactory
            ->createContext($this, $root), $this, $this->constraintValidatorFactory, $this->typedDataManager);
    }
    
    /**
     * {@inheritdoc}
     */
    public function inContext(ExecutionContextInterface $context) : ContextualValidatorInterface {
        return new RecursiveContextualValidator($context, $this, $this->constraintValidatorFactory, $this->typedDataManager);
    }
    
    /**
     * {@inheritdoc}
     *
     * @param \Drupal\Core\TypedData\TypedDataInterface $typed_data
     *   A typed data object containing the value to validate.
     */
    public function getMetadataFor($typed_data) : MetadataInterface {
        if (!$typed_data instanceof TypedDataInterface) {
            throw new \InvalidArgumentException('The passed value must be a typed data object.');
        }
        return new TypedDataMetadata($typed_data);
    }
    
    /**
     * {@inheritdoc}
     */
    public function hasMetadataFor($value) : bool {
        return $value instanceof TypedDataInterface;
    }
    
    /**
     * {@inheritdoc}
     */
    public function validate($value, $constraints = NULL, $groups = NULL) : ConstraintViolationListInterface {
        return $this->startContext($value)
            ->validate($value, $constraints, $groups)
            ->getViolations();
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateProperty($object, $propertyName, $groups = NULL) : ConstraintViolationListInterface {
        return $this->startContext($object)
            ->validateProperty($object, $propertyName, $groups)
            ->getViolations();
    }
    
    /**
     * {@inheritdoc}
     */
    public function validatePropertyValue($objectOrClass, $propertyName, $value, $groups = NULL) : ConstraintViolationListInterface {
        // Just passing a class name is not supported.
        if (!is_object($objectOrClass)) {
            throw new \LogicException('Typed data validation does not support passing the class name only.');
        }
        return $this->startContext($objectOrClass)
            ->validatePropertyValue($objectOrClass, $propertyName, $value, $groups)
            ->getViolations();
    }

}