chart.setSize(600, 250);
final LinearGradientFill fill = Fills.newLinearGradientFill(0, BLUE, 100);
fill.addColorAndOffset(RED, 0);
chart.setBackgroundFill(fill);
chart.setAreaFill(Fills.newSolidFill(Color.newColor(GRAY, 70)));
String url = chart.toURLString();
// EXAMPLE CODE END. Use this url string in your web or
// Internet application.
Logger.getLogger(Logger.GLOBAL_LOGGER_NAME).info(url);
String expectedString = "http://chart.apis.google.com/chart?cht=gom&chd=e:5m&chl=Fast&chs=600x250&chdl=VELOCITY&chts=000000,14&chtt=How+Fast%3F&chco=1148D4,5766DE,DB3270,D41111&chf=bg,lg,0,0000FF,1.0,FF0000,0.0|c,s,808080B2";