Gráficas en Java con JFreeChart

/*
 * ventanaGrafica.java
 *
 * Created on 9 de agosto de 2003, 9:11
 */
import org.jfree.data.*;
import org.jfree.chart.*;
import org.jfree.chart.plot.*;
import java.awt.image.*;

/**
 *
 * @author  Roberto Canales
 */
public class ventanaGrafica extends java.awt.Frame {

    BufferedImage grafica = null;

    /** Creates new form ventanaGrafica */
    public ventanaGrafica() {
        initComponents();
    }

    /** This method is called from within the constructor to
     * initialize the form.
     * WARNING: Do NOT modify this code. The content of this method is
     * always regenerated by the Form Editor.
     */
    private void initComponents() {

        addWindowListener(new java.awt.event.WindowAdapter() {
            public void windowClosing(java.awt.event.WindowEvent evt) {
                exitForm(evt);
            }
        });

        pack();
    }

    /** Exit the Application */
    private void exitForm(java.awt.event.WindowEvent evt) {
        System.exit(0);
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String args[]) {

        ventanaGrafica miventana = new ventanaGrafica();
        miventana.setSize(400,400);
        miventana.show();
    }

    public BufferedImage creaImagen()
    {
        XYSeries series = new XYSeries("Evolucion");
        series.add(1, 23);
        series.add(2, 34);
        series.add(3, 51);
        series.add(4, 67);
        series.add(5, 89);
        series.add(6, 121);
        series.add(7, 137);
        XYDataset juegoDatos= new XYSeriesCollection(series);

        JFreeChart chart = ChartFactory.createLineXYChart
        ("Sesiones en Adictos al Trabajo",
        "Meses","Sesiones",juegoDatos,PlotOrientation.VERTICAL,
        false,
        false,
        true                // Show legend
        );

         BufferedImage image = chart.createBufferedImage(300,300);
        return image;
    }

    public void paint(java.awt.Graphics g) {
        //super.paint(g);

        if(grafica == null)
        {
            grafica = this.creaImagen();
        }
        g.drawImage(grafica,30,30,null);
    }

}

    

/*
 * ejemploGraficasServlet.java
 *
 * Created on 10 de agosto de 2003, 14:25
 */

import java.io.*;
import java.net.*;

import javax.servlet.*;
import javax.servlet.http.*;

import org.jfree.data.*;
import org.jfree.chart.*;
import org.jfree.chart.plot.*;

/**
 *
 * @author  Roberto Canales
 * @version
 */
public class ejemploGraficasServlet extends HttpServlet
{

    public JFreeChart crearChart()
    {
        XYSeries series = new XYSeries("Evolucion Sesiones");
        series.add(1, 23);
        series.add(2, 34);
        series.add(3, 51);
        series.add(4, 67);
        series.add(5, 89);
        series.add(6, 121);
        series.add(7, 137);
        XYDataset juegoDatos= new XYSeriesCollection(series);

        JFreeChart chart = ChartFactory.createLineXYChart("Sesiones en Adictos al Trabajo",
        "Meses", "Sesiones", juegoDatos,
        PlotOrientation.VERTICAL,
        true,true,true
        );

        return chart;
    }


    int getParamEntero(HttpServletRequest request,String pNombre, int pDefecto)
    {
            String param = request.getParameter(pNombre);

            if (param == null || param.compareTo("") == 0)
            {
                return pDefecto;
            }

            return Integer.parseInt(param);

    }


    /** Processes requests for both HTTP GET and POST methods.
     * @param request servlet request
     * @param response servlet response
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        response.setContentType("image/jpeg");
      
        OutputStream salida = response.getOutputStream();
        JFreeChart grafica = crearChart();

        int ancho = getParamEntero(request,"ancho",400);
        int alto = getParamEntero(request,"alto",300);

        ChartUtilities.writeChartAsJPEG(salida,grafica,ancho,alto);

        salida.close();
    }

    /** Handles the HTTP GET method.
     * @param request servlet request
     * @param response servlet response
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

}

    

/*
 * ejemploGraficasServlet.java
 *
 * Created on 10 de agosto de 2003, 14:25
 */

import java.io.*;
import java.net.*;

import javax.servlet.*;
import javax.servlet.http.*;

import org.jfree.data.*;
import org.jfree.chart.*;
import org.jfree.chart.plot.*;

import java.sql.*;

/**
 *
 * @author  Roberto Canales
 * @version
 */
public class ejemploGraficasServlet extends HttpServlet
{

    public JFreeChart crearChart()
    {
        // este código no es optimo ..... hay que usar pools
        try
        {
            Driver d = (Driver)Class.forName("com.mysql.jdbc.Driver").newInstance();
        }
        catch (Exception e)
        {
            System.out.println(e);
        }

        // GET CONNECTION
        Connection con = null;

        try
        {
            con = DriverManager.getConnection("jdbc:mysql://localhost/test","","");
        }
        catch(Exception e)
        {
            System.out.println(e);
        }

        JDBCXYDataset xyDataset = new JDBCXYDataset(con,"select x as meses,y as sesiones from sesiones");
        
        JFreeChart chart = ChartFactory.createLineXYChart("Sesiones en Adictos al Trabajo",
        "Meses",
        "Sesiones",
        xyDataset,
        PlotOrientation.VERTICAL,
        true,
        true,
        true                // Show legend
        );

        try
        {
            con.close();
        }
        catch(Exception e)
        {
            System.out.println("Error al desconectar " + e);
        }
        return chart;
    }


    int getParamEntero(HttpServletRequest request,String pNombre, int pDefecto)
    {
            String param = request.getParameter(pNombre);

            if (param == null || param.compareTo("") == 0)
            {
                return pDefecto;
            }

            return Integer.parseInt(param);

    }


    /** Processes requests for both HTTP GET and POST methods.
     * @param request servlet request
     * @param response servlet response
     */
    protected void processRequest(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        response.setContentType("image/jpeg");

        OutputStream salida = response.getOutputStream();
        JFreeChart grafica = crearChart();

        int ancho = getParamEntero(request,"ancho",400);
        int alto = getParamEntero(request,"alto",300);

        ChartUtilities.writeChartAsJPEG(salida,grafica,ancho,alto);

        salida.close();
    }

    /** Handles the HTTP GET method.
     * @param request servlet request
     * @param response servlet response
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
        processRequest(request, response);
    }

}