Hola, necesito urgentemente su ayuda!!!, necesito saber como mostrar una grafica en una jsp mediante un servlet. Profavor ayudenme.
Este es mi codigo del servlet:
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYDotRenderer;
import org.jfree.data.xy.XYDataset;
import org.jfree.data.xy.XYSeries;
import org.jfree.data.xy.XYSeriesCollection;
import org.jfree.chart.ChartUtilities;
/*
* @author Aniushka
*/
public class Servlet_Datos extends HttpServlet {
public JFreeChart DevuelveGrafica (){
final XYSeries series = new XYSeries("Random Data");
for (int i = 0; i < 1440; i++) {
final double x = Math.random();
final double y = Math.random();
series.add(x, y);
}
final XYDataset data = new XYSeriesCollection(series);
// create a scatter chart...
final boolean withLegend = true;
final JFreeChart chart = ChartFactory.createScatterPlot(
"Scatter plot timing", "X", "Y",
data,
PlotOrientation.VERTICAL,
withLegend,
false,
false
);
final XYPlot plot = chart.getXYPlot();
plot.setRenderer(new XYDotRenderer());
return chart;
}
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("image/jpeg");
OutputStream salida = response.getOutputStream();
JFreeChart dibujar = DevuelveGrafica();
ChartUtilities.writeChartAsJPEG(salida,dibujar,400 ,300);
}
// <editor-fold defaultstate="collapsed" desc="HttpServlet methods. Click on the + sign on the left to edit the code.">
/**
* Handles the HTTP <code>GET</code> method.
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Handles the HTTP <code>POST</code> method.
* @param request servlet request
* @param response servlet response
* @throws ServletException if a servlet-specific error occurs
* @throws IOException if an I/O error occurs
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
/**
* Returns a short description of the servlet.
* @return a String containing servlet description
*/
@Override
public String getServletInfo() {
return "Short description";
}// </editor-fold>
}
