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());

                && 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 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);