// head method
                        responseData =
                                client.execute(RequestDataBuilder.newRequestData().head().url(url).weight(urlQueue.getWeight()).build());
                        if (responseData == null) {
                            return true;
                        }

        try (final ResponseData responseData = client.execute(RequestDataBuilder.newRequestData().get().url(url).build())) {
            if (responseData.getRedirectLocation() != null) {
                final Set<RequestData> childUrlList = new HashSet<>();
                childUrlList.add(RequestDataBuilder.newRequestData().get().url(responseData.getRedirectLocation()).build());

        urlList.clear();
        urlList.add(RequestDataBuilder.newRequestData().get().url("http://www.example.com").build());
        urlList = fessXpathTransformer.convertChildUrlList(urlList);
        assertEquals(1, urlList.size());
        assertEquals("http://www.example.com", urlList.get(0).getUrl());

        urlList.clear();
        urlList.add(RequestDataBuilder.newRequestData().get().url("http://www.example.com").build());

            }
            String u = url;
            for (int i = 0; i < maxRedirectCount; i++) {
                try (final ResponseData responseData = client.execute(RequestDataBuilder.newRequestData().get().url(u).build())) {
                    if (StringUtil.isNotBlank(responseData.getRedirectLocation())) {
                        u = responseData.getRedirectLocation();
                        continue;

                && isValidCanonicalUrl(responseData.getUrl(), canonicalUrl)) {
            final Set<RequestData> childUrlSet = new HashSet<>();
            childUrlSet.add(RequestDataBuilder.newRequestData().get().url(canonicalUrl).build());
            logger.info("Canonical URL redirect: from={}, to={}", responseData.getUrl(), canonicalUrl);

        final StatsKeyObject keyObj = paramMap.get(Constants.CRAWLER_STATS_KEY) instanceof final StatsKeyObject sko ? sko : null;
        try (final ResponseData responseData = client.execute(RequestDataBuilder.newRequestData().get().url(url).build())) {
            if (responseData.getRedirectLocation() != null) {
                return responseData.getRedirectLocation();
            }

        final StreamResponse response = new StreamResponse(StringUtil.EMPTY);
        final ResponseData responseData = client.execute(RequestDataBuilder.newRequestData().get().url(url).build());
        if (responseData.getHttpStatusCode() == 404) {
            response.httpStatus(responseData.getHttpStatusCode());
            CloseableUtil.closeQuietly(responseData);