Draw a Graphical Chart in response to a user request
response.setContentType("image/jpeg");
// Create an Image
BufferedImage img =
new BufferedImage(W, H,
BufferedImage.TYPE_INT_RGB);
// Get the Image's Graphics, and draw.
Graphics2D g = img.createGraphics();
// In real life this would call some charting software...
g.setColor(Color.white);
g.fillRect(0,0, W, H);
g.setColor(Color.green);
g.fillOval(100, 75, 50, 50);
// Write the output
OutputStream os = response.getOutputStream();
ImageOutputStream ios = ImageIO.createImageOutputStream(os);
if (!ImageIO.write(img, "jpeg", ios)) {
log("Boo hoo, failed to write JPEG");
}
ios.close();
os.close();
