class NacosDynamicConfiguration implements DynamicConfiguration {

    @Override
    public String getConfig(String key, String group, long timeout) throws IllegalStateException {
        String resolvedGroup = resolveGroup(group);
        try {
            long nacosTimeout = timeout < 0 ? getDefaultTimeout() : timeout;
            if (StringUtils.isEmpty(resolvedGroup)) {
                resolvedGroup = DEFAULT_GROUP;
            }
            return configService.getConfig(key, resolvedGroup, nacosTimeout);
        } catch (NacosException e) {
            logger.error(e.getMessage());
        }
        return null;
    }

      NacosDynamicConfiguration(URL url);

}