if (url == null) {
            url = ComponentUtil.getMessageManager().getMessage(locale, "labels.search_unknown");
        }
        doc.put(fessConfig.getResponseFieldUrlLink(), getUrlLink(doc));
        String createdStr;
        final Date created = DocumentUtil.getValue(doc, fessConfig.getIndexFieldCreated(), Date.class);
        if (created != null) {

                        docMap.put(fessConfig.getResponseFieldContentDescription(), viewHelper.getContentDescription(docMap));
                        docMap.put(fessConfig.getResponseFieldUrlLink(), viewHelper.getUrlLink(docMap));
                        docMap.put(fessConfig.getResponseFieldSitePath(), viewHelper.getSitePath(docMap));
                    }

     * The value is, e.g. url_link <br>
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getResponseFieldUrlLink();

    /**
     * Get the value for the key 'response.field.site_path'. <br>
     * The value is, e.g. site_path <br>