public function findFile($class)
 {
     if (false === ($file = apc_fetch($this->prefix . $class))) {
         apc_store($this->prefix . $class, $file = parent::findFile($class));
     }
     return $file;
 }
    /**
     * Finds a file by class name while caching lookups to APC.
     *
     * @param string $class A class name to resolve to file
     *
     * @return string|null The path, if found
     */
    public function findFile($class)
    {
        $file = apcu_fetch($this->prefix.$class, $success);

        if (!$success) {
            apcu_store($this->prefix.$class, $file = parent::findFile($class) ?: null);
        }

        return $file;
    }