Code

void pullLinksApart(Diagram diagram)
{
	// group links by coordinates of their first control point
	HashMap<String, ArrayList<DiagramLink>> linksByStartPoint = new HashMap<>();
	for (DiagramLink link : diagram.getLinks())
	{
		String key = link.getStartPoint().toString();
		ArrayList<DiagramLink> links = linksByStartPoint.get(key);
		if (links == null)
		{
			links = new ArrayList<DiagramLink>();
			linksByStartPoint.put(key, links);
		}
		links.add(link);
	}

	// for each group with two or more links
	for (ArrayList<DiagramLink> links : linksByStartPoint.values())
	{
		if (links.size() < 2)
			continue;

		DiagramLink firstLink = links.get(0);
		Rectangle2D.Float nodeRect = firstLink.getOrigin().getBounds();
		Point2D.Float point = firstLink.getStartPoint();
		if (point.x == nodeRect.x || point.x == nodeRect.x + nodeRect.width)
		{
			// sort the links by position of their end points
			Collections.sort(links, new Comparator<DiagramLink>()
			{
				@Override
				public int compare(DiagramLink l1, DiagramLink l2)
				{
					float y1 = l1.getStartPoint().y;
					float y2 = l2.getStartPoint().y;
					if (y1 < y2) return -1;
					if (y1 > y2) return 1;
					return 0;
				}
			});

			float d = nodeRect.height / (links.size() + 1);
			float y = nodeRect.y + d;
			for (DiagramLink link : links)
			{
				Point2D.Float p1 = link.getStartPoint();
				Point2D.Float p2 = link.getControlPoints().get(1);
				if (link.getShape() == LinkShape.Cascading && p2.y == p1.y)
					p2.y = y;
				p1.y = y;
				link.updateFromPoints();
				y += d;
			}
		}
	}
}