private PictogramElement createTransition(ContainerShape srcState,ContainerShape destState,MyTransition myTransition) {

		ChopboxAnchor srcAnchor=GraphitiUi.getPeService().createChopboxAnchor(srcState);
		srcAnchor.setReferencedGraphicsAlgorithm(srcState.getGraphicsAlgorithm());
		srcState.getAnchors().add(srcAnchor);

		ChopboxAnchor destAnchor=GraphitiUi.getPeService().createChopboxAnchor(destState);
		destAnchor.setReferencedGraphicsAlgorithm(destState.getGraphicsAlgorithm());
		destState.getAnchors().add(destAnchor);

		AddConnectionContext context = new AddConnectionContext(srcAnchor, destAnchor);
		context.setNewObject(myTransition);
		PictogramElement connection = iFeatureProvider.addIfPossible(context);

		return connection;
	}

PictogramElement connection = iFeatureProvider.addIfPossible(context);
if( connection == null){
    // Add was not possible,  probably no addFeature available as Michael states
}

//ADDMyTransitionFeature.java

public boolean canAdd(IAddContext context) {		
			return true;
	}


public PictogramElement add(IAddContext context) {
		IAddConnectionContext addConContext = (IAddConnectionContext) context;
		MyTransition addedTransition = (MyTransition) context.getNewObject();
		final Diagram targetDiagram = (Diagram) context.getTargetContainer();

		IPeCreateService peCreateService = Graphiti.getPeCreateService();
		
		// CONNECTION WITH POLYLINE
		Connection connection = peCreateService.createFreeFormConnection(targetDiagram);
		Anchor sourceAnchor = addConContext.getSourceAnchor();
		connection.setStart(sourceAnchor);
		Anchor targetAnchor = addConContext.getTargetAnchor();
		connection.setEnd(targetAnchor);

		IGaService gaService = Graphiti.getGaService();
		Polyline polyline = gaService.createPolyline(connection);
		polyline.setBackground(manageColor(IColorConstant.BLACK));
		polyline.setForeground(manageColor(IColorConstant.BLACK));
		polyline.setLineWidth(5);

		// creating the link
		link(connection, addedTransition);

		// add Text decorator for the reference name
		ConnectionDecorator textDecorator = peCreateService.createConnectionDecorator(connection, true, 0.5, true);
		Text text = gaService.createDefaultText(targetDiagram,textDecorator);
		StyleUtil.setStyleForTransition(targetDiagram,text);

		MyTransition eReference = (MyTransition) context.getNewObject();
		text.setValue(eReference.getName());

		// add the image decorator for the reference name
		ConnectionDecorator imgDecorator = peCreateService.createConnectionDecorator(connection, true, 0.4, true);
		Image eventImg = Graphiti.getGaService().createImage(imgDecorator,TRANSITION_IMG);
		Graphiti.getGaService().setLocationAndSize(eventImg, 0, 0, 25, 25);

		
		ConnectionDecorator cd;
		cd = peCreateService.createConnectionDecorator(connection, false, 1.0, true);
		createArrow(cd);

		// create link and wire it
		link(cd, addedTransition);
		
		return connection;
	}

ChopboxAnchor srcAnchor=GraphitiUi.getPeService().createChopboxAnchor(srcState);

Anchor srcAnchor=getAnchor(srcState);
....
	private Anchor getAnchor(PictogramElement pe) {
		Anchor anchor= null;
		if (pe instanceof Anchor) {
			anchor= (Anchor) pe;
		} else if (pe instanceof AnchorContainer) {
			anchor= Graphiti.getPeService().getChopboxAnchor((AnchorContainer) pe);
		}
		return anchor;
	}