Symfony\Component\Validator\Constraint::validatedBy PHP Method

    public function validatedBy()
    {
        return get_class($this).'Validator';
    }

 /**
  * Returns the validator for the supplied constraint.
  *
  * @param Constraint $constraint A constraint
  *
  * @return ConstraintValidatorInterface A validator for the supplied constraint
  *
  * @throws UnexpectedTypeException When the validator is not an instance of ConstraintValidatorInterface
  */
 public function getInstance(Constraint $constraint)
 {
     $name = $constraint->validatedBy();
     if (!isset($this->validators[$name])) {
         switch (get_class($constraint)) {
             case self::BASE_NAMESPACE . '\\All':
                 $name = self::BASE_NAMESPACE . '\\LegacyAllValidator';
                 break;
             case self::BASE_NAMESPACE . '\\Choice':
                 $name = self::BASE_NAMESPACE . '\\LegacyChoiceValidator';
                 break;
             case self::BASE_NAMESPACE . '\\Collection':
                 $name = self::BASE_NAMESPACE . '\\LegacyCollectionValidator';
                 break;
             case self::BASE_NAMESPACE . '\\Count':
                 $name = self::BASE_NAMESPACE . '\\LegacyCountValidator';
                 break;
             case self::BASE_NAMESPACE . '\\Length':
                 $name = self::BASE_NAMESPACE . '\\LegacyLengthValidator';
                 break;
             case self::FORM_BASE_NAMESPACE . '\\Form':
                 $name = self::FORM_BASE_NAMESPACE . '\\LegacyFormValidator';
                 break;
         }
         $this->validators[$name] = new $name();
     } elseif (is_string($this->validators[$name])) {
         $this->validators[$name] = $this->container->get($this->validators[$name]);
     }
     if (!$this->validators[$name] instanceof ConstraintValidatorInterface) {
         throw new UnexpectedTypeException($this->validators[$name], 'Symfony\\Component\\Validator\\ConstraintValidatorInterface');
     }
     return $this->validators[$name];
 }