AbstractVaadinChartExample the vaadin8 charts demo have the class,but i ca

[https://demo.vaadin.com/charts/#SplineUpdatingEachSecond]
(https://demo.vaadin.com/charts/#SplineUpdatingEachSecond)
I have seem the demo of vaadin 8 charts use:
public class SplineUpdatingEachSecond extends AbstractVaadinChartExample
but my dependency package did not have the AbstractVaadinChartExample/
So.I need this AbstractVaadinChartExample class.

You can find it here, in the Charts sources, as well as all of the demo code: https://github.com/vaadin/charts/blob/master/examples/src/main/java/com/vaadin/addon/charts/examples/AbstractVaadinChartExample.java

-Olli