code: public List<FilterType<PortletDescriptor>> getAllFilter()
     {
        List<FilterType<PortletDescriptor>> list = new ArrayList<FilterType<PortletDescriptor>>();
        List<Node> nodeList = model.get("filter");
        for(Node node: nodeList)
        {
           FilterType<PortletDescriptor>  type = new FilterTypeImpl<PortletDescriptor>(this, "filter", model, node);
           list.add(type);
        }
        return list;
     }
docs: Returns all <code>filter</code> elements
  @return list of <code>filter</code>