code: public int insertOrdered(XEvent event) {
  		try {
  			return events.insertOrdered(event);
  		} catch (IOException e) {
  			e.printStackTrace();
  			return -1;
  		}
  	}
docs: Insert the event in an ordered manner, if timestamp information is
  available in this trace.
  
  @param event
  the event to be inserted.
  @return index of the inserted event.