JAVA桌面截图

         Robot robot = new Robot();   
//要捕捉的屏幕显示范围，下面以全屏示例说明  
Rectangle rect = new Rectangle(Toolkit.getDefaultToolkit().getScreenSize());
BufferedImage bm = robot.createScreenCapture(rect);

         File file = new File("c:/sys.jpg");
FileOutputStream   outputstream = new FileOutputStream(file);
JPEGCodec.createJPEGEncoder(outputstream).encode(bm);   
ImageIO.write(bm, "jpg", outputstream);