code: public JspPropertyGroupType<JspConfigType<T>> getOrCreateJspPropertyGroup()
     {
        List<Node> nodeList = childNode.get("jsp-property-group");
        if (nodeList != null &&  nodeList.size() > 0)
        {
           return new JspPropertyGroupTypeImpl<JspConfigType<T>>(this, "jsp-property-group", childNode, nodeList.get(0));
        }
        return createJspPropertyGroup();
     }
docs: If not already created, a new <code>jsp-property-group</code> element will be created and returned.
  Otherwise, the first existing <code>jsp-property-group</code> element will be returned.
  @return the instance defined for the element <code>jsp-property-group</code>