Let me explain one approach I had implemented some time back. I had used jfreechart-1.0.0-pre2
1) Create an org.jfree.data.xy.XYSeries object and add all sets of x-coordinate and y-coordinate in a sample space. you can create as many XYSeries object as number of sample spaces.
2) Create org.jfree.data.xy.XYSeriesCollection object and add all such XYSeries objects in XYSeriesCollection object.
3) Create 2 objects of org.jfree.chart.axis.ValueAxis , one defining x-axis and other defining y-axis. There are numerous types axis classes available in the package like Data, logarithemic , .. etc
4) Create org.jfree.chart.renderer.xy.XYItemRenderer�object. Again there are numerous options available for Renderer. Select type of renderer depending type of graph you want.
5) Create org.jfree.chart.plot.XYPlot object using XYSeriesCollection object , ValueAxis objects and XYItemRenderer object as arguments in the constructor
6) Create org.jfree.chart.JFreeChart object using chart title(
String) , font, and XYPlot object as arguments in the constructor
7) use org.jfree.chart.servlet.ServletUtilities.saveChartAsPNG() (or use other utility methods) to save the chart in temporary directory
8) Finally use org.jfree.chart.servlet.DisplayChart
servlet to display the chart in the JSP page. You need to pass on the temporary chart image file name obtained from ServletUtilities.saveChartAsPNG() to DisplayChart servlet.
i.e <img src="/servlet/DisplayChart?filename=<%=filename%>" width="750" height="450" />
make sure you put the jfreechart jar in your application classpath
hope this helps