IPeService peService = Graphiti.getPeService();
IGaService gaService = Graphiti.getGaService();
Participant participant = (Participant) BusinessObjectUtil.getFirstElementOfType(context.getPictogramElement(),
Participant.class);
ContainerShape containerShape = (ContainerShape) context.getPictogramElement();
if (participant.getParticipantMultiplicity() != null) {
Shape shape = peService.createShape(containerShape, false);
peService.setPropertyValue(shape, MULTIPLICITY_MARKER, Boolean.toString(true));
Rectangle invisibleRectangle = gaService.createInvisibleRectangle(shape);
GraphicsAlgorithm parentGa = containerShape.getGraphicsAlgorithm();
int x = (parentGa.getWidth() / 2) - 10;
int y = parentGa.getHeight() - 20;
gaService.setLocationAndSize(invisibleRectangle, x, y, 20, 20);
Polyline line1 = gaService.createPolyline(invisibleRectangle, new int[] { 0, 0, 0, 20 });