Tutorial: Creating a simple graph with JFreeChart within ICY

 public class BarChartDemo1 extends Plugin implements PluginImageAnalysis
{

    JPanel mainPanel = GuiUtil.generatePanel("Graph");
    IcyFrame mainFrame = GuiUtil.generateTitleFrame("Chart demo", mainPanel, new Dimension(300, 100), true, true, true,
            true);

    private static CategoryDataset createDataset()
    {

        // row keys...
        String series1 = "First";
        String series2 = "Second";
        String series3 = "Third";

        // column keys...
        String category1 = "Category 1";
        String category2 = "Category 2";
        String category3 = "Category 3";
        String category4 = "Category 4";
        String category5 = "Category 5";

        // create the dataset...
        DefaultCategoryDataset dataset = new DefaultCategoryDataset();

        dataset.addValue(1.0, series1, category1);
        dataset.addValue(4.0, series1, category2);
        dataset.addValue(3.0, series1, category3);
        dataset.addValue(5.0, series1, category4);
        dataset.addValue(5.0, series1, category5);

        dataset.addValue(5.0, series2, category1);
        dataset.addValue(7.0, series2, category2);
        dataset.addValue(6.0, series2, category3);
        dataset.addValue(8.0, series2, category4);
        dataset.addValue(4.0, series2, category5);

        dataset.addValue(4.0, series3, category1);
        dataset.addValue(3.0, series3, category2);
        dataset.addValue(2.0, series3, category3);
        dataset.addValue(3.0, series3, category4);
        dataset.addValue(6.0, series3, category5);

        return dataset;

    }

    private static JFreeChart createChart(CategoryDataset dataset)
    {

        // create the chart...
        JFreeChart chart = ChartFactory.createBarChart("Bar Chart Demo 1", // chart title
                "Category", // domain axis label
                "Value", // range axis label
                dataset, // data
                PlotOrientation.VERTICAL, // orientation
                true, // include legend
                true, // tooltips?
                false // URLs?
                );

        // NOW DO SOME OPTIONAL CUSTOMISATION OF THE CHART...

        // set the background color for the chart...
        chart.setBackgroundPaint(Color.white);

        // get a reference to the plot for further customisation...
        CategoryPlot plot = (CategoryPlot) chart.getPlot();

        // set the range axis to display integers only...
        NumberAxis rangeAxis = (NumberAxis) plot.getRangeAxis();
        rangeAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());

        // disable bar outlines...
        BarRenderer renderer = (BarRenderer) plot.getRenderer();
        renderer.setDrawBarOutline(false);

        // set up gradient paints for series...
        GradientPaint gp0 = new GradientPaint(0.0f, 0.0f, Color.blue, 0.0f, 0.0f, new Color(0, 0, 64));
        GradientPaint gp1 = new GradientPaint(0.0f, 0.0f, Color.green, 0.0f, 0.0f, new Color(0, 64, 0));
        GradientPaint gp2 = new GradientPaint(0.0f, 0.0f, Color.red, 0.0f, 0.0f, new Color(64, 0, 0));
        renderer.setSeriesPaint(0, gp0);
        renderer.setSeriesPaint(1, gp1);
        renderer.setSeriesPaint(2, gp2);

        CategoryAxis domainAxis = plot.getDomainAxis();
        domainAxis.setCategoryLabelPositions(CategoryLabelPositions.createUpRotationLabelPositions(Math.PI / 6.0));
        // OPTIONAL CUSTOMISATION COMPLETED.

        return chart;

    }

    @Override
    public void compute()
    {

        CategoryDataset dataset = createDataset();
        JFreeChart chart = createChart(dataset);
        ChartPanel chartPanel = new ChartPanel(chart);
        chartPanel.setFillZoomRectangle(true);
        chartPanel.setMouseWheelEnabled(true);
        chartPanel.setPreferredSize(new Dimension(500, 270));
        mainPanel.add(chartPanel);

        mainFrame.pack();
        mainFrame.setVisible(true);
        mainFrame.center();

        addIcyFrame(mainFrame);

    }

}