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

        String feedUUID = helper.getMD5Code(feed.getLink().getBytes());
        String fullPath = this.configManager.joinPathToDataDir(feedUUID);

        if (!helper.isPathExists(fullPath)) {
            boolean isSuccess = new File(fullPath).mkdir();
            if (!isSuccess) {
                throw new RuntimeException("can not create dir at path:" + fullPath);
            }
        }

        initDirsForEveryEntry(feed, fullPath);
    }