Creating a dynamic line chart using jfree chart in java

how can I create a dynamic line chart using a jFree chart in java that shows data 2 hours before and also gives an empty space where the data shows 2 hours later than the current time. For example, suppose the current time is 4pm, so the charts display data from 2pm to 6pm. From 2:00 to 16:00, the chart shows the line and from 16:00 to 18:00, it provides an empty space that fills the time until the time when the chart moves, which means that the tail of this chart starts from the middle and moves to the right, similarly stock market chart.

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Yes you can do it. A few days ago I ran into a similar problem. Please check here:

http://dirtyhandsphp.blogspot.in/2012/07/how-to-draw-dynamic-line-or-timeseries.html


DynamicLineAndTimeSeriesChart.java

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.Timer;
import javax.swing.JPanel;

import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.ValueAxis;
import org.jfree.chart.plot.XYPlot;
import org.jfree.data.time.Millisecond;
import org.jfree.data.time.TimeSeries;
import org.jfree.data.time.TimeSeriesCollection;
import org.jfree.data.xy.XYDataset;
import org.jfree.ui.ApplicationFrame;
import org.jfree.ui.RefineryUtilities;

/**
 * An example to show how we can create a dynamic chart.
*/
public class DynamicLineAndTimeSeriesChart extends ApplicationFrame implements ActionListener {

    /** The time series data. */
    private TimeSeries series;

    /** The most recent value added. */
    private double lastValue = 100.0;

    /** Timer to refresh graph after every 1/4th of a second */
    private Timer timer = new Timer(250, this);

    /**
     * Constructs a new dynamic chart application.
     *
     * @param title  the frame title.
     */
    public DynamicLineAndTimeSeriesChart(final String title) {

        super(title);
        this.series = new TimeSeries("Random Data", Millisecond.class);

        final TimeSeriesCollection dataset = new TimeSeriesCollection(this.series);
        final JFreeChart chart = createChart(dataset);

        timer.setInitialDelay(1000);

        //Sets background color of chart
        chart.setBackgroundPaint(Color.LIGHT_GRAY);

        //Created JPanel to show graph on screen
        final JPanel content = new JPanel(new BorderLayout());

        //Created Chartpanel for chart area
        final ChartPanel chartPanel = new ChartPanel(chart);

        //Added chartpanel to main panel
        content.add(chartPanel);

        //Sets the size of whole window (JPanel)
        chartPanel.setPreferredSize(new java.awt.Dimension(800, 500));

        //Puts the whole content on a Frame
        setContentPane(content);

        timer.start();

    }

    /**
     * Creates a sample chart.
     *
     * @param dataset  the dataset.
     *
     * @return A sample chart.
     */
    private JFreeChart createChart(final XYDataset dataset) {
        final JFreeChart result = ChartFactory.createTimeSeriesChart(
            "Dynamic Line And TimeSeries Chart",
            "Time",
            "Value",
            dataset,
            true,
            true,
            false
        );

        final XYPlot plot = result.getXYPlot();

        plot.setBackgroundPaint(new Color(0xffffe0));
        plot.setDomainGridlinesVisible(true);
        plot.setDomainGridlinePaint(Color.lightGray);
        plot.setRangeGridlinesVisible(true);
        plot.setRangeGridlinePaint(Color.lightGray);

        ValueAxis xaxis = plot.getDomainAxis();
        xaxis.setAutoRange(true);

        //Domain axis would show data of 60 seconds for a time
        xaxis.setFixedAutoRange(60000.0);  // 60 seconds
        xaxis.setVerticalTickLabels(true);

        ValueAxis yaxis = plot.getRangeAxis();
        yaxis.setRange(0.0, 300.0);

        return result;
    }
    /**
     * Generates an random entry for a particular call made by time for every 1/4th of a second.
     *
     * @param e  the action event.
     */
    public void actionPerformed(final ActionEvent e) {

        final double factor = 0.9 + 0.2*Math.random();
        this.lastValue = this.lastValue * factor;

        final Millisecond now = new Millisecond();
        this.series.add(new Millisecond(), this.lastValue);

        System.out.println("Current Time in Milliseconds = " + now.toString()+", Current Value : "+this.lastValue);
    }

    /**
     * Starting point for the dynamic graph application.
     *
     * @param args  ignored.
     */
    public static void main(final String[] args) {

        final DynamicLineAndTimeSeriesChart demo = new DynamicLineAndTimeSeriesChart("Dynamic Line And TimeSeries Chart");
        demo.pack();
        RefineryUtilities.centerFrameOnScreen(demo);
        demo.setVisible(true);

    }

}  

Hope this solves your problem.

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