code: public void setController(Object object, GraphicsController controller, int eventMask) {
  		doSetController(getGroup(object), controller, eventMask);
  	}
docs: Set the controller on an element of this <code>GraphicsContext</code> so it can react to events.
  
  @param object
  the element on which the controller should be set.
  @param controller
  The new <code>GraphicsController</code>
  @param eventMask
  a bitmask to specify which events to listen for {@link com.google.gwt.user.client.Event}