code: static EventCallBackStruct getCallBackStruct(Hashtable map, int id) {
          Enumeration keys = map.keys();
          while (keys.hasMoreElements()) {
              String name = (String) keys.nextElement();
              EventCallBackStruct callback_struct =
                      (EventCallBackStruct) map.get(name);
              if (callback_struct.id == id)
                  return callback_struct;
          }
          return null;
      }
docs: ===============================================================