Jfreechart

public class GenerateGraph
{
    /* No. of points displayed */
    private static final int COUNT = 50;

    /* Speed of graph in milliseconds */
    private static final int FAST = 100;

    /* to generate random no. (for test purpose only) */
    private static final Random random = new Random();

    /* to run timer after 'FAST' seconds */
    private Timer timer;

    /* hoolds the data to be displayed */
    float data[] = new float[COUNT];

    JPanel graph()
    {
        /* init class MilliDTSC */
        final MilliDTSC dataset = new MilliDTSC(50, COUNT, new Millisecond());

        /* add the dataset */
        dataset.addSeries(data, 0, "");

        /* set time base = Millisecond */
        dataset.setTimeBase(new Millisecond(100, new Second()));

        /* create a new chart with this information */
        JFreeChart chart = ChartFactory.createTimeSeriesChart("", "Time (ms)",
                "Speed (kmph)", dataset);

        /* set X and Y axis properties */
        XYPlot plot = chart.getXYPlot();
        final ValueAxis domain = plot.getDomainAxis();

        domain.setAutoRange(true);


        NumberAxis axis = new NumberAxis();
        axis.setTickUnit(new NumberTickUnit(100));




        /* what should be done here now */



        ValueAxis range = plot.getRangeAxis();
        range.setRange(0, 100);

        /* Chart panel extends javax.swing.JPanel and holds a jfreechart */
        MyChartPanel c = new MyChartPanel(chart);
        /*
         * used to run a timer thread (daemon) in infinite loop to append data
         * to the chart
         */
        timer = new Timer(FAST, new ActionListener()
        {

            float[] newData = new float[1];

            public void actionPerformed(ActionEvent e)
            {
                /*
                 * this flag is updated, if TestScreen panel is removed from the
                 * main frame, so accordingly, this thread should stop
                 */
                if (TestScreen.exitFlag)
                    timer.stop();
                newData[0] = 15 + random.nextInt(25);
                dataset.advanceTime();
                dataset.appendData(newData);
                SwingUtilities.invokeLater(new Runnable()
                {
                    public void run()
                    {
                        //TestScreen.leftPanel.repaint();
                        //TestScreen.leftPanel.revalidate();
                    }
                });
                ;
            }
        });
        /* start timer thread */
        timer.start();
        return c;
    }