public function getInstaller($class, Engine_Package_Manager_Operation_Abstract $operation, array $params = null) { $key = $operation->getKey(); if (!isset($this->_installers[$key])) { if (!class_exists($class)) { // Forces autoload throw new Engine_Package_Installer_Exception(sprintf('Unable to load installer class %s', $class)); } $params['db'] = $this->getDb(); $params['vfs'] = $this->getVfs(); $this->_installers[$key] = new $class($operation, $params); } return $this->_installers[$key]; }