JFreeChart - IntervalMarker vertical?

In the examples provided by JFreechart, we see that it is possible to display horizontal IntervalMarkers. I wou开发者_开发技巧ld like to build vertical IntervalMarkers and I do not find the way to do that using this example.

In Cartesian coordinates , the domain is orthogonal to the range, so

final IntervalMarker target = new IntervalMarker(10.0, 20.0);
target.setLabel("Target Domain");
...
plot.addDomainMarker(target, Layer.BACKGROUND);