code: public GroupConversionType<GetterType<T>> getOrCreateConvertGroup()
     {
        List<Node> nodeList = childNode.get("convert-group");
        if (nodeList != null &&  nodeList.size() > 0)
        {
           return new GroupConversionTypeImpl<GetterType<T>>(this, "convert-group", childNode, nodeList.get(0));
        }
        return createConvertGroup();
     }
docs: If not already created, a new <code>convert-group</code> element will be created and returned.
  Otherwise, the first existing <code>convert-group</code> element will be returned.
  @return the instance defined for the element <code>convert-group</code>