chartConfig.getSubtitle().setText("Source: Wikipedia.org");
CategoryAxis xAxis = new CategoryAxis();
xAxis.setCategories(Arrays.asList("1750", "1800", "1850", "1900",
"1950", "1999", "2050"));
Tick tick = new Tick();
tick.setPlacement(TickmarkPlacement.ON);
xAxis.setTick(tick);
LinkedHashSet<XAxis> xAxesSet = new LinkedHashSet<InvientChartsConfig.XAxis>();
xAxesSet.add(xAxis);
chartConfig.setXAxes(xAxesSet);