import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.awt.*;
import java.awt.image.*;
import com.sun.image.codec.jpeg.*;
import java.util.*;

public class CriarPoligonos extends HttpServlet {

   public void doGet(HttpServletRequest request,
                     HttpServletResponse response)
                    throws ServletException, IOException {

     response.setContentType("image/pjpeg");

     //Cria a imagem
     int width=200, height=200;
     BufferedImage image = new BufferedImage(
       width, height, BufferedImage.TYPE_INT_RGB);

     //Obtendo o contexto de Graphics
     Graphics g = image.getGraphics();

     // Preenchendo a cor de fundo
     g.setColor(Color.white);
     g.fillRect(0, 0, width, height);

     //Cria um polígono aleatóriamente
     Polygon poly = new Polygon();
     Random random = new Random();
     for (int i=0; i < 20; i++) {
       poly.addPoint(random.nextInt(width),
         random.nextInt(height));
     }

     //Preenche o polígono criado.
     g.setColor(Color.cyan);
     g.fillPolygon(poly);

     //Liberando os contextos
     g.dispose();

     //Enviando a imagem
     ServletOutputStream sos = response.getOutputStream();
     JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(sos);
     encoder.encode(image);

   }
}