}

    /**
     * Logs a message using the provided LogHelper.
     * @param logHelper The LogHelper instance.
     * @param key The LogType key.
     * @param objs The objects to log.
     */
    protected void log(final LogHelper logHelper, final LogType key, final Object... objs) {
        if (logHelper != null) {
            logHelper.log(key, objs);
        }
    }

    /**

import org.codelibs.fess.crawler.entity.UrlQueue;
import org.codelibs.fess.crawler.exception.CrawlingAccessException;
import org.codelibs.fess.crawler.helper.LogHelper;
import org.codelibs.fess.crawler.log.LogType;

/**
 * Implementation of the {@link LogHelper} interface.
 * This class provides methods for logging various events during the crawling process.
 * It uses Log4j2 for logging.
 *
 * <p>

        // but we can verify the class structure
        assertNotNull(crawlerLogHelper);
        assertTrue(CrawlerLogHelper.class.getSuperclass().getSimpleName().contains("LogHelper"));
    }

                if (lastModified == null) {
                    return true;
                }
                urlQueue.setLastModified(lastModified.getTime());
                log(logHelper, LogType.CHECK_LAST_MODIFIED, crawlerContext, urlQueue);

                if (responseData == null) {
                    // head method

                .singleton("intervalController", DefaultIntervalController.class)
                .singleton("sitemapsHelper", SitemapsHelper.class)
                .singleton("logHelper", LogHelperImpl.class)
                .singleton("encodingHelper", EncodingHelper.class)
                .singleton("contentLengthHelper", ContentLengthHelper.class)