anchor.diff:  		Object perimeter = state.getStyle().get(Constants.STYLE_PERIMETER);
   
   		// Converts string values to objects
  -		if (perimeter instanceof String)
  +		if (perimeter is String)
   		{
   			String str = String.valueOf(perimeter);
   			Object tmp = StyleRegistry.getValue(str);
  
positive.code: 				: Constants.STYLE_TARGET_PORT;
  		String id = Utils.getString(state._style, key);
  
  		if (id != null && _graph.getModel() instanceof GraphModel)
  		{
  			CellState tmp = getState(((GraphModel) _graph.getModel())
  					.getCell(id));
  
negative.code: 	{
  		if (edge != null)
  		{
  			List<Point2d> pts = new List<Point2d>();
  			pts.add(edge.getAbsolutePoint(0));
  			EdgeStyleFunction edgeStyle = getEdgeStyle(edge, points, source,
  					target);
  