class ApcuBackendFactory

class ApcuBackendFactory implements CacheFactoryInterface {
    
    /**
     * The site prefix string.
     *
     * @var string
     */
    protected $sitePrefix;
    
    /**
     * The cache tags checksum provider.
     *
     * @var \Drupal\Core\Cache\CacheTagsChecksumInterface
     */
    protected $checksumProvider;
    
    /**
     * The APCU backend class to use.
     *
     * @var string
     */
    protected $backendClass;
    
    /**
     * Constructs an ApcuBackendFactory object.
     *
     * @param string $root
     *   The app root.
     * @param string $site_path
     *   The site path.
     * @param \Drupal\Core\Cache\CacheTagsChecksumInterface $checksum_provider
     *   The cache tags checksum provider.
     * @param \Drupal\Component\Datetime\TimeInterface $time
     *   The time service.
     */
    public function __construct($root, $site_path, CacheTagsChecksumInterface $checksum_provider, TimeInterface $time) {
        $this->sitePrefix = Settings::getApcuPrefix('apcu_backend', $root, $site_path);
        $this->checksumProvider = $checksum_provider;
        $this->backendClass = 'Drupal\\Core\\Cache\\ApcuBackend';
    }
    
    /**
     * Gets ApcuBackend for the specified cache bin.
     *
     * @param $bin
     *   The cache bin for which the object is created.
     *
     * @return \Drupal\Core\Cache\ApcuBackend
     *   The cache backend object for the specified cache bin.
     */
    public function get($bin) {
        return new $this->backendClass($bin, $this->sitePrefix, $this->checksumProvider, $this->time);
    }

}