static Map objectID_map;

static long objectID(O o) {
  if (o == null) ret 0;
  Map generalMap = cast getOpt(javax(), 'generalMap);
  if (generalMap == null) fail("Please upgrade JavaX");
  synchronized(generalMap) {
    Map map = cast generalMap.get("objectIDs");
    if (map == null)
      generalMap.put("objectIDs", map = new WeakHashMap);
    Long l = cast map.get(o);
    if (l == null) {
      l = toLong(generalMap.get("lastObjectID"))+1;
      generalMap.put("lastObjectID", l);
      map.put(o, l);
    }
    ret l;
  }
}