/**
* @param ElementInterface $element
*
* @throws ValidationError
*/
public function validate(ElementInterface $element)
{
if ($element->isLeaf()) {
if (strlen($element->getContent()) === 0) {
throw new ValidationError(sprintf($this->message, 'content'));
}
} else {
if (count($element->getChildren()) === 0) {
throw new ValidationError(sprintf($this->message, 'children[]'));
}
}
}