你好：
我有一个疑问，当Registry调用destroy后不会去清除AbstractRegistryFactory中的缓存，导致以同样的参数再次获取的时候得到了一个已经无法使用的Registry。这个时设计的时候就认为不该这么使用吗？
Map<URL, Set<NotifyListener>> destroySubscribed = new HashMap<>(getSubscribed());
        if (!destroySubscribed.isEmpty()) {
            for (Map.Entry<URL, Set<NotifyListener>> entry : destroySubscribed.entrySet()) {
                URL url = entry.getKey();
                for (NotifyListener listener : entry.getValue()) {
                    try {
                        unsubscribe(url, listener);
                        if (logger.isInfoEnabled()) {
                            logger.info("Destroy unsubscribe url " + url);
                        }
                    } catch (Throwable t) {
                        logger.warn("Failed to unsubscribe url " + url + " to registry " + getUrl() + " on destroy, cause: " + t.getMessage(), t);
                    }
                }
            }
        }
    }
    protected boolean acceptable(URL urlToRegistry) {
        String pattern = registryUrl.getParameter(ACCEPTS_KEY);
        if (StringUtils.isEmpty(pattern)) {
            return true;
        }
        return Arrays.stream(COMMA_SPLIT_PATTERN.split(pattern))
                .anyMatch(p -> p.equalsIgnoreCase(urlToRegistry.getProtocol()));
    }
    @Override
    public String toString() {
        return getUrl().toString();
    }
    private class SaveProperties implements Runnable {