code: public function validate(\ElggEntity $entity) {
  
  		$validation = new ValidationStatus();
  
  		$value = get_input($this->getShortname());
  		if (is_string($value)) {
  			$value = strip_tags($value);
  		}
  		if (is_null($value) || $value == '') {
  			if ($this->isRequired()) {
  				$validation->setFail(elgg_echo('prototyper:validate:error:required', array($this->getLabel())));
  			}
  		} else {
  			$validation = $this->applyValidationRules($value, $validation, $entity);
  		}
  
  		return $validation;
  	}
docs: {@inheritdoc}