protected function _normalizeConfig()
    {
        $classMap = $this->getConfig('classMap');
        $this->_classMap = array_merge($this->_classMap, $classMap);

        $lists = $this->getConfig('lists');
        $defaultStrategy = $this->getConfig('defaultStrategy');

        foreach ($lists as $alias => $config) {
            if (is_numeric($alias)) {
                unset($lists[$alias]);
                $alias = $config;
                $config = [];
                $lists[$alias] = $config;
            }

            if (is_string($config)) {
                $config = ['prefix' => strtoupper($config)];
            }

            if (empty($config['strategy'])) {
                $config['strategy'] = $defaultStrategy;
            }

            $lists[$alias] = $this->strategy($alias, $config['strategy'])
                ->initialize($config)
                ->getConfig();
        }

        $this->setConfig('lists', $lists, false);
    }