_makeBackend example

    public function __construct(array $options = array())
    {
        parent::__construct($options);

        if ($this->_options['slow_backend'] === null) {
            Zend_Cache::throwException('slow_backend option has to set');
        } elseif ($this->_options['slow_backend'] instanceof Zend_Cache_Backend_ExtendedInterface) {
            $this->_slowBackend = $this->_options['slow_backend'];
        } else {
            $this->_slowBackend = Zend_Cache::_makeBackend(
                $this->_options['slow_backend'],
                $this->_options['slow_backend_options'],
                $this->_options['slow_backend_custom_naming'],
                $this->_options['slow_backend_autoload']
            );
            if (!in_array('Zend_Cache_Backend_ExtendedInterface', class_implements($this->_slowBackend))) {
                Zend_Cache::throwException('slow_backend must implement the Zend_Cache_Backend_ExtendedInterface interface');
            }
        }

        if ($this->_options['fast_backend'] === null) {
            

    public static function factory($frontend, $backend, $frontendOptions = array(), $backendOptions = array(), $customFrontendNaming = false, $customBackendNaming = false, $autoload = false)
    {
        if (is_string($backend)) {
            $backendObject = self::_makeBackend($backend, $backendOptions, $customBackendNaming, $autoload);
        } else {
            if ((is_object($backend)) && (in_array('Zend_Cache_Backend_Interface', class_implements($backend)))) {
                $backendObject = $backend;
            } else {
                self::throwException('backend must be a backend name (string) or an object which implements Zend_Cache_Backend_Interface');
            }
        }
        if (is_string($frontend)) {
            $frontendObject = self::_makeFrontend($frontend, $frontendOptions, $customFrontendNaming, $autoload);
        } else {
            if (is_object($frontend)) {
                

    private function createBackend($backend, $backendOptions)
    {
        if (strtolower($backend) === 'auto') {
            $backend = $this->createAutomaticBackend($backendOptions);
        } else {
            if (strtolower($backend) === 'apc') {
                $backend = 'apcu';
            }

            $backend = Zend_Cache::_makeBackend($backend, $backendOptions);
        }

        return $backend;
    }

    /** * @param array $backendOptions * * @return Zend_Cache_Backend */
    private function createAutomaticBackend($backendOptions = [])
    {