Java Screenshot How to

http://schmidt.devlib.org/java/save-screenshot.html

[code]

/*
* Screenshot.java (requires Java 1.4+)
*/

import java.awt.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.*;

public class Screenshot {
 public static void main(String[] args) throws Exception {
  // make sure we have exactly two arguments,
  // a waiting period and a file name
  if (args.length != 2) {
   System.err.println("Usage: java Screenshot " +
    "WAITSECONDS OUTFILE.png");
   System.exit(1);
  }
  // check if file name is valid
  String outFileName = args[1];
  if (!outFileName.toLowerCase().endsWith(".png")) {
   System.err.println("Error: output file name must " +
    "end with \".png\".");
   System.exit(1);
  }
  // wait for a user-specified time
  try {
   long time = Long.parseLong(args[0]) * 1000L;
   System.out.println("Waiting " + (time / 1000L) +
    " second(s)...");
   Thread.sleep(time);
  } catch(NumberFormatException nfe) {
   System.err.println(args[0] + " does not seem to be a " +
    "valid number of seconds.");
   System.exit(1);
  }
  // determine current screen size
  Toolkit toolkit = Toolkit.getDefaultToolkit();
  Dimension screenSize = toolkit.getScreenSize();
  Rectangle screenRect = new Rectangle(screenSize);
  // create screen shot
  Robot robot = new Robot();
  BufferedImage image = robot.createScreenCapture(screenRect);
  // save captured image to PNG file
  ImageIO.write(image, "png", new File(outFileName));
  // give feedback
  System.out.println("Saved screen shot (" + image.getWidth() +
   " x " + image.getHeight() + " pixels) to file \"" +
   outFileName + "\".");
  // use System.exit if the program hangs after writing the file;
  // that's an old bug which got fixed only recently
  // System.exit(0);
 }
}

[/code]