\r
public GetElementClassRequest(ElementFactory elementFactory, Resource element, ICanvasContext canvas, IDiagram diagram) {\r
super(element, canvas);\r
+ if (elementFactory == null)\r
+ throw new IllegalArgumentException("elementFactory == null for " + element + " in diagram " + diagram + " with context " + canvas);\r
this.elementFactory = elementFactory; \r
this.diagram = diagram;\r
}\r