docs: public static boolean contentCheckTagAction(
          String elementList,
          String prefix,
          boolean checkall,
          boolean checknone,
          I_CmsXmlDocument content,
          Locale locale) {
  
          boolean found = false;
          String[] elements = CmsStringUtil.splitAsArray(elementList, ',');
          for (int i = (elements.length - 1); i >= 0; i--) {
  
              String element = CmsXmlUtils.concatXpath(prefix, elements[i].trim());
              found = found || content.hasValue(element, locale);
  
              if (found && checknone) {
                  // found an item that must not exist
                  return false;
              }
              if (found && !checkall && !checknone) {
                  // we need to find only one item
                  return true;
              }
          }
  
          if (!found && checknone) {
              // no item found as expected
              return true;
          }
  
          return found;
      }