ServletOutputStream out = res.getOutputStream();
try {
// Get the image location from the path info
String source = req.getPathTranslated();
if (source == null) {
throw new ServletException("Extra path information " +
"must point to an image");
}
// Load the image (from bytes to an Image object)
MediaTracker mt = new MediaTracker(frame); // frame acts as an ImageObserver
Image image = Toolkit.getDefaultToolkit().getImage(source);
mt.addImage(image, 0);
try {
mt.waitForAll();
}
catch (InterruptedException e) {
getServletContext().log(e, "Interrupted while loading image");
throw new ServletException(e.getMessage());
}
// Construct a matching-size off screen graphics context
int w = image.getWidth(frame);
int h = image.getHeight(frame);
Image offscreen = frame.createImage(w, h);
g = offscreen.getGraphics();
// Draw the image to the off screen graphics context
g.drawImage(image, 0, 0, frame);
// Write CONFIDENTIAL over its top
g.setFont(new Font("Monospaced", Font.BOLD | Font.ITALIC, 30));
g.drawString("CONFIDENTIAL", 10, 30);
// Encode the off screen graphics into a GIF and send it to the client
res.setContentType("image/gif");
GifEncoder encoder = new GifEncoder(offscreen, out);
encoder.encode();
}
finally {
// Clean up resources
if (g != null) g.dispose();
}
