}
    public void registerGraphic(org.cougaar.core.qos.frame.Frame f, ShapeGraphic graphic) {        if (f == null || graphic == null)            return;        synchronized (lock) {            if (graphics.get(f) != null)               throw new IllegalArgumentException("Error: "+graphic+" is already registered for frame "+f);            //if (graphics.get(f) == null) {                graphics.put(f, graphic);            //}        }    }