Hi Friend,

Try the following code:

import java.io.*;
import java.util.*;
import java.awt.*;
import org.jfree.ui.*;
import org.jfree.chart.*;
import org.jfree.chart.plot.*;
import org.jfree.data.xy.*;
import java.text.*;
import org.jfree.chart.axis.NumberAxis;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFCell;

public class TrendLine extends ApplicationFrame {
public TrendLine(final String title) {
super(title);
final XYDataset dataset = createDataset();
final JFreeChart chart = createChart(dataset);
final ChartPanel chartPanel = new ChartPanel(chart);
chartPanel.setPreferredSize(new java.awt.Dimension(500, 270));
setContentPane(chartPanel);
}
private XYDataset createDataset() {
short a=0;
short b=1;
String st1="",st2="";
String filename ="C:/data.xls";
if (filename != null && !filename.equals("")) {
try{
FileInputStream fs =new FileInputStream(filename);
HSSFWorkbook wb = new HSSFWorkbook(fs);
for (int k = 0; k < wb.getNumberOfSheets(); k++){
HSSFSheet sheet = wb.getSheetAt(k);
int rows = sheet.getPhysicalNumberOfRows();
for (int r = 1; r < rows; r++){
HSSFRow row = sheet.getRow(r);
if (row != null) {
int cells = row.getPhysicalNumberOfCells();
HSSFCell cell1 = row.getCell(a);
if (cell1 != null){
String value = null;
switch (cell1.getCellType()){
case HSSFCell.CELL_TYPE_FORMULA :
value = "FORMULA ";
break;
case HSSFCell.CELL_TYPE_NUMERIC :
value = ""+cell1.getNumericCellValue();
break;
case HSSFCell.CELL_TYPE_STRING :
value = cell1.getStringCellValue();
break;
}
st1+=value+" ";

}
HSSFCell cell2 = row.getCell(b);
if (cell2 != null){
String value = null;
switch (cell2.getCellType()){
case HSSFCell.CELL_TYPE_FORMULA :
value = "FORMULA ";
break;
case HSSFCell.CELL_TYPE_NUMERIC :
value = ""+cell2.getNumericCellValue();
break;
case HSSFCell.CELL_TYPE_STRING :
value = cell2.getStringCellValue();
break;
}
st2+=value+" ";
}
}
}
}
}
catch (Exception ex){ }
}
String arr1[]=st1.split(" ");
String arr2[]=st2.split(" ");
final XYSeries series1 = new XYSeries("Graph");
for(int i=0;i<arr1.length;i++){
String s1=arr1[i];
double n1=Double.parseDouble(s1);
String s2=arr2[i];
double n2=Double.parseDouble(s2);
series1.add(n1, n2);
}

DecimalFormat df = new DecimalFormat("####0.00");
double weight[]=new double[7];
double trend[]=new double[7];
trend[0]=40;
for(int i=0;i<arr1.length;i++){
weight[i]=Double.parseDouble(arr2[i]);
}
double value1=weight[0]-trend[0];
double newvalue1=value1/10;
double roundedValue1=Double.parseDouble(df.format(newvalue1));
trend[0]=trend[0]+roundedValue1;
System.out.println(trend[0]);

continue........

double value2=weight[1]-trend[0];
double newvalue2=value2/10;
double roundedValue2=Double.parseDouble(df.format(newvalue2));
trend[1]=trend[0]+roundedValue2;
System.out.println(trend[1]);

double value3=weight[2]-trend[1];
double newvalue3=value3/10;
double roundedValue3=Double.parseDouble(df.format(newvalue3));
trend[2]=trend[1]+roundedValue3;
System.out.println(trend[2]);

double value4=weight[3]-trend[2];
double newvalue4=value4/10;
double roundedValue4=Double.parseDouble(df.format(newvalue4));
trend[3]=trend[2]+roundedValue4;
System.out.println(trend[3]);

double value5=weight[4]-trend[3];
double newvalue5=value5/10;
double roundedValue5=Double.parseDouble(df.format(newvalue5));
trend[4]=trend[3]+roundedValue5;
System.out.println(trend[4]);

double value6=weight[5]-trend[4];
double newvalue6=value6/10;
double roundedValue6=Double.parseDouble(df.format(newvalue6));
trend[5]=trend[4]+roundedValue6;
System.out.println(trend[5]);

double value7=weight[6]-trend[5];
double newvalue7=value7/10;
double roundedValue7=Double.parseDouble(df.format(newvalue7));
trend[6]=trend[5]+roundedValue7;
System.out.println(trend[6]);

final XYSeries series2 = new XYSeries("TrendLine");
for(int i=0;i<arr1.length;i++){
String s1=arr1[i];
double n1=Double.parseDouble(s1);
series2.add(n1, trend[i]);
}
final XYSeriesCollection dataset = new XYSeriesCollection();
dataset.addSeries(series1);
dataset.addSeries(series2);


return dataset;
}
private JFreeChart createChart(final XYDataset dataset) {
final JFreeChart chart = ChartFactory.createXYLineChart(
"",
"Number of Days",
"Weight",
dataset,
PlotOrientation.VERTICAL,
true,
true,
false
);
chart.setBackgroundPaint(Color.white);

return chart;
}
public static void main(String[]args){

final TrendLine demo = new TrendLine("Multi Line Chart");
demo.setSize(300,300);
RefineryUtilities.centerFrameOnScreen(demo);
demo.setVisible(true);
}
}

For the above code, we have created an excel file with two fields 'number of days and weight'.

Hope that it will be helpful for you.
Thanks

thanx a lot for ur input ..i hav been able to complete my project ...