public void clearImageStore(BaseFeed feed) {
        if (!hasInited) {
            throw new RuntimeException("there is something error occured in init()");
        }

        if (feed == null) {
            throw new NullPointerException("the arg:feed can not be null");
        }

        if (StringUtils.isEmpty(feed.getLink())) {
            throw new IllegalArgumentException("the arg:feed's property:link can not be null or empty");
        }

        String key = this.getImageCacheKey(feed.getLink());
        this.jedis.del(key);
    }