public function setMinLength($minLength)
    {
        if (!is_integer($minLength)) {
            throw new InvalidArgumentException(
                'Min length must be an integer.'
            );
        }

        if ($minLength < 0) {
            throw new InvalidArgumentException(
                'Min length must be a positive integer (>=0).'
            );
        }

        $this->minLength = $minLength;

        return $this;
    }