private BxBounds parseElementContainingVertexes(Element el) {
   ArrayList<Element> vs = getChildren("Vertex", el);
   if (vs.isEmpty()) {
     return null;
   }
   ArrayList<ComparablePair<Integer, Integer>> list =
       new ArrayList<ComparablePair<Integer, Integer>>();
   int minx = Integer.MAX_VALUE;
   int maxx = Integer.MIN_VALUE;
   int miny = Integer.MAX_VALUE;
   int maxy = Integer.MIN_VALUE;
   for (Element v : vs) {
     int x = Integer.parseInt(v.getAttribute("x"));
     if (x < minx) minx = x;
     if (x > maxx) maxx = x;
     int y = Integer.parseInt(v.getAttribute("y"));
     if (y < miny) miny = y;
     if (y > maxy) maxy = y;
     list.add(new ComparablePair<Integer, Integer>(x, y));
   }
   Collections.sort(list);
   ComparablePair<Integer, Integer> mine = list.get(0);
   ComparablePair<Integer, Integer> maxe = list.get(list.size() - 1);
   BxBounds ret = new BxBounds(minx, miny, maxx - minx, maxy - miny);
   if (ret.getHeight() == 0 || ret.getWidth() == 0) {
     log.warn("problems with height or width points are:");
     for (ComparablePair<Integer, Integer> pa : list) {
       log.warn("\t" + pa.o1 + " , " + pa.o2);
     }
   }
   return ret;
 }
 private ArrayList<Element> getChildren(String name, Element el) {
   ArrayList<Element> list = new ArrayList<Element>();
   NodeList nl = el.getChildNodes();
   for (int i = 0; i < nl.getLength(); i++) {
     Node n = nl.item(i);
     if (n instanceof Element) {
       Element e = (Element) n;
       if (e.getTagName().equalsIgnoreCase(name)) {
         list.add(e);
       }
     }
   }
   return list;
 }
 private BxZoneLabel parseClassification(Element elClassicfication) {
   ArrayList<Element> eli = getChildren("Category", elClassicfication);
   Element catEl = eli.isEmpty() ? null : eli.get(0);
   if (catEl == null) {
     eli = getChildren("Type", elClassicfication);
     catEl = eli.isEmpty() ? null : eli.get(0);
   }
   if (catEl == null) {
     return null;
   }
   String val = catEl.getAttribute("Value");
   if (val == null) {
     return null;
   }
   if (zoneLabelMap.containsKey(val.toLowerCase())) {
     return zoneLabelMap.get(val.toLowerCase());
   }
   return BxZoneLabel.OTH_UNKNOWN;
 }