}
        } catch (final Exception e) {
            logger.warn("Failed to create thumbnail for {}", entity, e);
        }
    }

    public boolean offer(final Map<String, Object> docMap) {
        for (final ThumbnailGenerator generator : generatorList) {
            if (generator.isTarget(docMap)) {
                final String path = getImageFilename(docMap);

            long counter = 0;
            final Deque<String> urlQueue = new LinkedList<>();
            final Set<String> processedUrls = new HashSet<>();
            urlQueue.offer(url);
            while (!urlQueue.isEmpty() && (maxAccessCount < 0 || counter < maxAccessCount)) {
                counter++;
                final Map<String, Object> localDataMap =

        }

        final File thumbnailFile = thumbnailManager.getThumbnailFile(doc);
        if (thumbnailFile == null) {
            if (fessConfig.isThumbnailEnabled()) {
                thumbnailManager.offer(doc);
            }
            // 404
            throw responseManager.new404("Thumbnail for " + form.docId + " is under generating.");
        }

    @Resource
    protected CrawlingInfoService crawlingInfoService;

    public static void addError(final String msg) {
        if (StringUtil.isNotBlank(msg)) {
            errors.offer(msg);
        }
    }

    public static class Options {

        @Option(name = "-s", aliases = "--sessionId", metaVar = "sessionId", usage = "Session ID")
        public String sessionId;

                final String thumbnailField = fessConfig.getIndexFieldThumbnail();
                docList.stream().forEach(doc -> {
                    if (!thumbnailManager.offer(doc)) {
                        if (logger.isDebugEnabled()) {
                            logger.debug("Removing {}={} from doc[{}]", thumbnailField, doc.get(thumbnailField),

            labelType.setCreatedTime(now);
            labelType.setUpdatedBy(Constants.SYSTEM_USER);
            labelType.setUpdatedTime(now);
        }
        tagQueue.offer(qName);
    }

    @Override
    public void endElement(final String uri, final String localName, final String qName) throws SAXException {
        if (logger.isDebugEnabled()) {