如何在图像的不同部分连续放置水印

Question

File sourceImageFile = new File（“ C：\ Users \ Documents \ NetBeansProjects \ MyProject \ src \ asian \ paints \ images \ stations.png”）;         BufferedImage sourceImage = ImageIO.read（sourceImageFile）;

    File watermarkImageFile = new File("C:\\Users\\Documents\\NetBeansProjects\\MyProject\\src\\asian\\paints\\images\\error_indicate.png");
    BufferedImage watermarkImage = ImageIO.read(watermarkImageFile);

    File destImageFile = new File("C:\\Users\\Desktop\\watermarked.png");

    // initializes necessary graphic properties
    Graphics2D g2d = (Graphics2D) sourceImage.getGraphics();
    AlphaComposite alphaChannel = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.3f);
    g2d.setComposite(alphaChannel);


    new Timer(0, new ActionListener()
    {
        @Override
        public void actionPerformed(ActionEvent e)
        {

            try {

       Jedis jedis = new Jedis("localhost");  

    // calculates the coordinate where the image is painted
    int topLeftX = Integer.parseInt(jedis.get("x")) ;
    int topLeftY = Integer.parseInt(jedis.get("y")) ;

    System.out.println("x " + topLeftX);
    System.out.println("y " + topLeftY);

    // paints the image watermark
    g2d.drawImage(watermarkImage, topLeftX, topLeftY, null);

    ImageIO.write(sourceImage, "png", destImageFile);
    g2d.dispose();

// System.out.println（“图像水印已添加到图像中。”）;

    ImageIcon iconLogo = new ImageIcon("C:\\Users\\Desktop\\watermarked.png");
      // In init() method write this code
     jLabel1.setIcon(iconLogo);


} catch (IOException ex) {
    System.err.println(ex);
}

        }
    }).start();

以上程序仅在执行时第一次更改水印位置。此后它将不会更改其位置。