Capturador de telas em java

import javax.swing.*;
import javax.swing.filechooser.FileFilter;
import java.awt.Robot;
import java.awt.Rectangle;
import java.awt.Dimension;
import java.awt.Image;
import java.awt.image.BufferedImage;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.Toolkit;
import javax.imageio.ImageIO;
import java.io.File;
import java.util.StringTokenizer;

/**
 *  Description of the Class
 *
 *@author     cmsilva (copernico@javafree.com.br)
 *@version    19 de Outubro de 2004
 */
public class ScreenCapture extends JFrame {
	private JLabel tela = new JLabel();
	private JToolBar barra = new JToolBar();
	private Image img;


	/**
	 *  Constructor for the ScreenCapture object
	 */
	public ScreenCapture() {
		super("Captura de tela");
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		tela.setBorder(BorderFactory.createLoweredBevelBorder());
		this.getContentPane().add(tela);
		this.barra.add(new CapturaAction());
		this.barra.add(new SalvarAction());
		this.getContentPane().add(barra, BorderLayout.NORTH);
	}


	/**
	 *  Captura a tela corrente
	 *
	 */
	private void capturar() throws Exception {
		Robot robo = new Robot();
		//Pega a image
		this.img = robo.createScreenCapture(new Rectangle(Toolkit.getDefaultToolkit().getScreenSize()));
		//Gera um thumbnail
		Image scaledImg = img.getScaledInstance((int) tela.getSize().getWidth(), (int) tela.getSize().getHeight(), Image.SCALE_FAST);
		//Exibe o thumbnail
		tela.setIcon(new ImageIcon(scaledImg));
		tela.validate();
	}


	/**
	 *  Salva a tela atual em PNG
	 *
	 */
	private void salvar() throws Exception {
		if (this.img == null) {
			return;
		}
		JFileChooser jfc = new JFileChooser();
		//Define um filtro para os arquivos exibidos no Chooser
		jfc.setFileFilter(
			new FileFilter() {
				public boolean accept(File f) {
					StringTokenizer stk = new StringTokenizer(f.getName(), ".");
					String ext = null;
					while (stk.hasMoreTokens()) {
						ext = stk.nextToken();
					}
					if (ext == null) {
						return false;
					}
					if (ext.equalsIgnoreCase("png")) {
						return true;
					} else {
						return false;
					}
				}


				public String getDescription() {
					return "Imagens PNG";
				}
			});
		int resp = jfc.showSaveDialog(this);
		if (resp == JFileChooser.CANCEL_OPTION) {
			return;
		}
		File outputFile = jfc.getSelectedFile();
		//Salva a imagem (api imageio)
		ImageIO.write((BufferedImage) this.img, "PNG", outputFile);
	}


	/**
	 *  Action para capturar a tela
	 *
	 *@author     cmsilva (copernico@javafree.com.br)
	 *@version    19 de Outubro de 2004
	 */
	private class CapturaAction extends AbstractAction {
		/**
		 *  Constructor for the Captura object
		 */
		public CapturaAction() {
			super("Capturar");
		}


		public void actionPerformed(ActionEvent ev) {
			try {
				capturar();
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}


	/**
	 *  Action para salvar a tela
	 *
	 *@author     cmsilva (copernico@javafree.com.br)
	 *@version    19 de Outubro de 2004
	 */
	private class SalvarAction extends AbstractAction {
		/**
		 *  Constructor for the SalvarAction object
		 */
		public SalvarAction() {
			super("Salvar");
		}
		public void actionPerformed(ActionEvent ev) {
			try {
				salvar();
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}


	/**
	 *  MAIN
	 *
	 *@param  args  Description of the Parameter
	 */
	public static void main(String args[]) {
		ScreenCapture app = new ScreenCapture();
		app.setSize(640, 480);
		app.show();
	}
}