final String xpath = xpathConfigMap.get(XPath.DEFAULT_CONTENT);
        if (StringUtil.isNotBlank(xpath)) {
            return xpath;
        }
        return fessConfig.getCrawlerDocumentHtmlContentXpath();
    }

    /**
     * Gets the XPath expression for extracting digest information.
     *
     * @param fessConfig the Fess configuration

     * comment: XPath to extract main content from HTML documents.
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getCrawlerDocumentHtmlContentXpath();

    /**
     * Get the value for the key 'crawler.document.html.lang.xpath'. <br>
     * The value is, e.g. //HTML/@lang <br>