} catch (Exception e) {
            fail("sendToSlack() should not throw an exception with blank URLs: " + e.getMessage());
        }
    }

    @Test
    public void test_sendToSlack_withNullWebhookUrls() {
        // Setup mock configuration with null webhook URLs
        ComponentUtil.setFessConfig(new MockFessConfig() {
            @Override
            public String getSlackWebhookUrls() {

            if (StringUtil.isNotBlank(getIncludedDocUrls())) {
                final List<Pattern> urlPatterList = new ArrayList<>();
                final String[] urls = getIncludedDocUrls().split("[\r\n]");
                for (final String u : urls) {
                    final String v = systemHelper.normalizeConfigPath(u);
                    if (StringUtil.isNotBlank(v)) {

    }

    /**
     * Adds a URL to the crawling queue.
     * @param url The URL to add.
     */
    public void addUrl(final String url) {
        try {
            urlQueueService.add(crawlerContext.sessionId, url);
            if (logger.isDebugEnabled()) {
                logger.debug("Added URL to queue: url={}, sessionId={}", url, crawlerContext.sessionId);
            }

    }

    /**
     * Parses and filters URL patterns from text based on protocol types.
     * Processes each line of the input text, filtering URLs based on web and file protocol support.
     *
     * @param text the raw text containing URL patterns, one per line
     * @param web true if web protocol URLs should be included
     * @param file true if file protocol URLs should be included

        }
    }

    /**
     * Extracts anchor URLs from the given object and converts them to RequestData objects.
     * The input object can be either a single string or a list of strings representing URLs.
     *
     * @param obj the object containing anchor URLs (String or List of Strings)
     * @return a set of RequestData objects for the anchor URLs, or null if no valid URLs found
     */

        this.updatedTime = value;
    }

    public String getUrls() {
        checkSpecifiedProperty("urls");
        return convertEmptyToNull(urls);
    }

    public void setUrls(String value) {
        registerModifiedProperty("urls");
        this.urls = value;
    }

    public String getUserAgent() {
        checkSpecifiedProperty("userAgent");

                    crawler.addUrl(u);
                    if (logger.isInfoEnabled()) {
                        logger.info("Target URL: {}", u);
                    }
                }
            }));

            // set included urls
            final AtomicBoolean urlEncodeDisabled = new AtomicBoolean(false);

            }
        }

    }

    /**
     * Stores child URLs to the crawling queue.
     * @param childUrlList The set of child URLs to store.
     * @param url The parent URL.
     * @param depth The depth of the child URLs.
     */
    protected void storeChildUrls(final Set<RequestData> childUrlList, final String url, final int depth) {

        for (int i = 0; i < threadCount; i++) {
            assertNull(exceptions[i], "Thread " + i + " threw exception");
        }

        // Verify all URLs were added
        synchronized (mockCallback) {
            assertEquals("All URLs should be added", threadCount * urlsPerThread, callback.deleteUrlList.size());
        }
    }

    /**
     * Test concurrent reads from deleteUrlList while synchronized.

    }

    /**
     * Retrieves a list of URLs that should be excluded from crawling based on failure counts.
     * URLs are excluded if they have failed more than the configured failure count threshold.
     * URLs can also be filtered by failure type using a regular expression pattern.
     *
     * @param configId the configuration ID to get excluded URLs for