static protected void expandElement(Element el,List<Element> list){
  list.addAll(el.getChildren("display"));
  List<Element> children=el.getChildren();
  for (int i=0; i < children.size(); i++) {
    expandElement(children.get(i),list);
  }
}

static protected void expandElement ( Element el , List < Element > list ) { list . addAll ( el . getChildren ( "display" ) ) ; List < Element > children = el . getChildren ( ) ; for ( int i = 0 ; i < children . size ( ) ; i ++ ) { expandElement ( children . get ( i ) , list ) ; } }
find all of the display elements descending from this element
