about JFreeCharts

Hai to all

            I am having one problem with jFreecharts.
            I am TimeSeriesCharts. While displaying X axis and Y axis
I didnt get the average speed value in the chart. My program is follows
as;
mport java.io.*;
import java.text.*;
import com.hashprompt.vtrack.init.TrackInitialize;
import org.jfree.chart.*;
import org.jfree.chart.ChartColor.*;
import org.jfree.chart.plot.*;
import org.jfree.chart.labels.*;
import org.jfree.chart.renderer.*;
import org.jfree.ui.*;
import java.util.*;
import java.awt.image.*;
import java.awt.*;
import org.jfree.data.time.*;
import org.jfree.data.xy.*;

import java.awt.geom.*;
import java.awt.event.*;
import org.jfree.chart.renderer.xy.*;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.axis.TickUnitSource;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.category.DefaultCategoryDataset;
import org.jfree.ui.RefineryUtilities;
import org.jfree.chart.annotations.XYLineAnnotation;
import org.jfree.data.time.TimeSeriesTableModel;
import org.jfree.chart.labels.*;
import com.hashprompt.vtrack.modules.log.*;
import com.hashprompt.vtrack.modules.util.*;

import java.sql.*;

public class GenerateSpeedChart
{
        private int speed_limit =0;
        private double avg_speed =0;
        private double speed =0.0;
        private int count =0;private int count =0;
        public GenerateSpeedChart(Double speed,int speed_limit )
        {

                this.speed_limit = speed_limit;
                this.speed = speed;
// this.count = count;
        }

        public void generateChart ( String truck_id,ResultSet rs ,
String file_name ) throws ChartException
        {
                try
                {
                        DefaultCategoryDataset dataSet = new
DefaultCategoryDataset();
                        TimeSeries series = new TimeSeries("Per Minute
Data", Minute.class);
                        int year = 0;
                        int month = 0;
                        int date = 0;
                        int hour = 0;
                        int minute = 0;
                        int second = 0;
                        String []tmp;
                        Hour hours;
                        Vector v = new Vector();
                        speed = 0;
                        while ( rs.next() )
                        {
                                tmp =
rs.getDate("date_time").toString().split("-");
                                if ( rs.getInt("speed")> 0 )
                                {
                                        speed += rs.getInt("speed");
                                        count++;
                                }
                                year = Integer.parseInt ( tmp[0] );
                                month = Integer.parseInt ( tmp[1] );
                                date = Integer.parseInt ( tmp[2] );
                                tmp =
rs.getTime("date_time").toString().split(":");
                                hour = Integer.parseInt ( tmp[0] );

minute = Integer.parseInt ( tmp[1] );
                                hours=new Hour(hour,date,month,year);
                                series.addOrUpdate(new Minute
(minute,hours),rs.getInt("speed"));

                        }
                        TimeSeriesCollection dataset = new
TimeSeriesCollection(series);
                        JFreeChart chart =
ChartFactory.createTimeSeriesChart(truck_id, "Time","Speed",
dataset,true,false,true );
                        chart.setBackgroundPaint(Color.white);
                        chart.getXYPlot().addRangeMarker(new
ValueMarker(speed_limit));
                        if(speed>0.0)
                        TrackInitialize.logger.info(count
+","+(speed/count));
                        avg_speed = speed/count;
                        XYPlot plot = chart.getXYPlot();
                        ValueMarker valuemarker = new
ValueMarker(avg_speed);
                        valuemarker.setPaint(Color.blue);
                // value.getValue(avg_speed);
                        chart.getXYPlot().addRangeMarker(valuemarker);
                        FileOutputStream fileOut = new
FileOutputStream(new File(file_name));

ChartUtilities.writeChartAsPNG(fileOut,chart,500,225);

                }
                catch ( Exception e )
                {
                        e.printStackTrace();
                        throw new ChartException ( "#" + ( new
Utilities() ).getMessage( e ) + "#1" );
                }
        }
}

Please any one HELP ME !!!!!
Thanks in advance.