Method getFilterInstance

/**
 * Method to get an image filter instance of a specified type.
 *
 * @param   string  $type  The image filter type to get.
 *
 * @return  ImageFilter
 *
 * @since   2.5.0
 * @throws  \RuntimeException
 */
protected function getFilterInstance($type)
{
    // Sanitize the filter type.
    $type = strtolower(preg_replace('#[^A-Z0-9_]#i', '', $type));
    // Verify that the filter type exists.
    $className = 'JImageFilter' . ucfirst($type);
    if (!class_exists($className)) {
        $className = __NAMESPACE__ . '\\Filter\\' . ucfirst($type);
        if (!class_exists($className)) {
            throw new \RuntimeException('The ' . ucfirst($type) . ' image filter is not available.');
        }
    }
    // Instantiate the filter object.
    $instance = new $className($this->getHandle());
    // Verify that the filter type is valid.
    if (!$instance instanceof ImageFilter) {
        throw new \RuntimeException('The ' . ucfirst($type) . ' image filter is not valid.');
    }
    return $instance;
}