Demat is a French Brittany word to said Hello (http://devri.bzh/dictionnaire/d/demat/).
Demat is a java library to generate Vega-lite representations.
Demat is under active development, nothing is stable ;-)
Let's run this script with Groovy
@GrabResolver(name = 'orbisgis', root = 'https://nexus.orbisgis.org/repository/orbisgis/')
@Grab(group = 'org.orbisgis', module = 'demat', version = '0.0.5')
import static org.orbisgis.demat.Demat.*;
def chart = Chart().description("A simple bar chart").name("A simple name")
.data(new Object[][]{{"a", "b", "c"}, {1, 22, 12}, {200, 300, 400}})
.mark_bar()
.encode(x("a").nominal(), y("b").quantitative());
chart.show();