simple chart is not rendered

[thombergs]

Reported by venkataramireddy1508, Nov 27, 2013
What steps will reproduce the problem?
1.followed the steps in gettingStarted page
2.
3.

What is the expected output? What do you see instead?
charts are not rendered

What version of the product are you using? On what operating system?
latest version wicket 6.x , on fedora

Please provide any additional information below.
I added this code in homepage.java constructor.

Options chartOptions = new Options();
    chartOptions.setChartOptions(new ChartOptions().setType(SeriesType.LINE)
                                                    .setMarginRight(130)    
                                                    .setMarginBottom(25));

    chartOptions.setTitle(new Title("Monthly Average Temperature").setX(-20));

    chartOptions.setSubtitle(new Title("Source: WorldClimate.com").setX(-20));

    Axis xAxis = new Axis();
    xAxis
        .setCategories(Arrays
            .asList(new String[] { "Jan", "Feb", "Mar", "Apr", "May", "Jun",
                "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }));
    chartOptions.setxAxis(xAxis);

    PlotLine plotLines = new PlotLine();
    plotLines
        .setValue(0f);
    plotLines
        .setWidth(1);
    plotLines
        .setColor(new HexColor("#999999"));

    Axis yAxis = new Axis();
    yAxis
        .setTitle(new Title("Temperature (��C)"));
    yAxis
        .setPlotLines(Collections
            .singletonList(plotLines));
    chartOptions.setyAxis(yAxis);

    Legend legend = new Legend();
    legend
        .setLayout(LegendLayout.VERTICAL);
    legend
        .setAlign(HorizontalAlignment.RIGHT);
    legend
        .setVerticalAlign(VerticalAlignment.TOP);
    legend
        .setX(-10);
    legend
        .setY(100);
    legend
        .setBorderWidth(0);
    chartOptions.setLegend(legend);

    Series<Number> series1 = new SimpleSeries();
    series1
        .setName("Tokyo");
    series1
        .setData(Arrays
            .asList(new Number[] { 7.0, 6.9, 9.5, 14.5, 18.2, 21.5, 25.2, 26.5,
                23.3, 18.3, 13.9, 9.6 }));
    chartOptions.addSeries(series1);

    Series<Number> series2 = new SimpleSeries();
    series2
        .setName("New York");
    series2
        .setData(Arrays
            .asList(new Number[] { -0.2, 0.8, 5.7, 11.3, 17.0, 22.0, 24.8,
                24.1, 20.1, 14.1, 8.6, 2.5 }));
    chartOptions.addSeries(series2);

    Series<Number> series3 = new SimpleSeries();
    series3
        .setName("Berlin");
    series3
        .setData(Arrays
            .asList(new Number[] { -0.9, 0.6, 3.5, 8.4, 13.5, 17.0, 18.6, 17.9,
                14.3, 9.0, 3.9, 1.0 }));
    chartOptions.addSeries(series3);

    Series<Number> series4 = new SimpleSeries();
    series4
        .setName("London");
    series4
        .setData(Arrays
            .asList(new Number[] { 3.9, 4.2, 5.7, 8.5, 11.9, 15.2, 17.0, 16.6,
                14.2, 10.3, 6.6, 4.8 }));
    chartOptions.addSeries(series4);


        System.out.println("Options: " + chartOptions);
    add(new Chart("chart", chartOptions));