Example of dynamic JPEG Image Generation by Servlet

// GenerateImage. java
/* Example of dynamically generating JPEG images */
Import java. awt .*;
Import java. awt. image .*;
Import com.sun.image.codec.jpeg. *; // encoding class
Java. util .*;
Javax. servlet .*;
Javax. servlet. http .*;
Java. io .*;

Class GenerateImage extends HttpServlet
Public void doGet (HttpServletRequest request, HttpServletResponse response)
Throws ServletException, java. io. IOException {

Response. setContentType ("image/jpeg "):
Int width = 200, height = 200;
BufferedImage image = BufferedImage (width, height, BufferedImage. TYPE_INT_RGB );
Graphics g = image. getGraphics ();
G. setColor (Color. white );
G. fillRect (0, 0, width, heitht );
Polygon poly = new Polygon ();
Random random = new Random ();
For (int I = 0; I <5; I ++)
{
Poly. addPoint (random. nextInt (width), random. nextInt (height ));
}
G. setColor (Color. cyan );
G. fillPolygon (poly );
G. dispose (); // The image is not shashed by Graphics.

ServletOutputStream sos = response. getOutputStream (); // binary
Required imageencoder encoder = required codec. createJPEGEncoder (sos); // create an encoder and output it to sos.
Encoder. encode (image );
}

Public void doPost (HttpServletRequest request, HttpServletResponse response)
Throws ServletException, java. io. IOException {
DoGet (request, response );
}

}