docs: public void connectBeginToEnd(SGraphSegment segment) {
  		if (segment.getGraph() != getGraph()) {
  			throw new IllegalArgumentException();
  		}
  		final SGraphPoint point = new SGraphPoint(getGraph());
  		setBegin(point);
  		segment.setEnd(point);
  
  		final SGraph g = getGraph();
  		assert g != null;
  		g.updatePointCount(-1);
  	}