How to code a time delay between plotting points in JFreeCharts?

Question

Is there a way to animate the plotting process of an xy-line chart using JFreeCharts? I want to be able to watch the program draw each line segment and connect them.

For example, if I paste this into the TextArea, "gtgtaaacaatatatggcg," I want to watch it graph each line segment one by one.

Thanks in advance! :)

My code is below:

import java.util.Scanner;
import java.applet.Applet;
import java.awt.*;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import org.jfree.chart.*;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.xy.*;

public class RandomWalkComplete extends Applet implements ActionListener
{
    Panel panel;
    TextArea textarea, outputArea;
    Button move,exit;
    String thetext;
    Scanner reader = new Scanner(System.in);
    String thetext2;
    Label instructions;

     int x,y;

    public void init() 
    {
        setSize(500,250); //set size of applet

         instructions=new Label("Paste the gene sequences in the " +
                "text field and press the graph button.");
        add(instructions);

        panel = new Panel();
        add(panel);
        setVisible(true);
        textarea= new TextArea(10,20);
        add(textarea);

        move=new Button("Graph");
        move.addActionListener(this);
        add(move);

        exit=new Button("Exit");
        exit.addActionListener(this);
        add(exit);
    }

    public void actionPerformed(ActionEvent e)
    {
        XYSeries series = new XYSeries("DNA Walk",false,true);

        x= 0; y = 0;
        series.add(x,y);

        if(e.getSource() == move)
        {
            thetext=textarea.getText(); //the text is the DNA bases pasted
            thetext=thetext.replaceAll(" ",""); //removes spaces
            thetext2 = "";

            for(int i=0; i<thetext.length(); i++)
           {
            char a = thetext.charAt(i);

            switch (a)
            {
                case 'A': case 'a'://moves right
                   x+=1; y+=0;
                   series.add(x,y);
                    break;

                case 'C': case 'c': //moves up
                  x+=0; y+=1;
                  series.add(x,y);
                    break;

                case 'G': case 'g': //move left
                  x-=1; y+=0;
                  series.add(x,y);
                    break;

                case 'T': case 't'://move down
                  x+=0; y-=1;
                  series.add(x,y);
                    break;

                default: // series.add(0,0);
                    break;
            }
            }                       
        XYDataset xyDataset = new XYSeriesCollection(series);
        JFreeChart chart = ChartFactory.createXYLineChart("DNA Random Walk",
            "", "", xyDataset, PlotOrientation.VERTICAL, true, true, false);
        ChartFrame frame1=new ChartFrame("DNA Random Walk",chart);
        frame1.setVisible(true);
        frame1.setSize(300,300);   
        }       
        if(e.getSource()==exit)
        {System.exit(0);}     
    }
    public void stop(){}
}

Answer 1

An instance of javax.swing.Timer works well for this, as described in How to Use Swing Timers.

Addendum: As @David Sauter observes, the scheduleAtFixedRate() method of java.util.Timer would be a suitable alternative. The article Using Timers in Swing Applications compares the two approaches.