java - 在Java中查找剪贴板图像的格式

Question

我正在使用这个从剪贴板获取图像:

if(Toolkit.getDefaultToolkit().getSystemClipboard().isDataFlavorAvailable(DataFlavor.imageFlavor)){
       ImageIcon IMG = new ImageIcon((BufferedImage) Toolkit.getDefaultToolkit().getSystemClipboard().getData(DataFlavor.imageFlavor));
}

现在我想使用ImageIO.write将这个图像保存在磁盘中；
如何找到要在 ImageIO.write 中用作 formatName 的图像格式(JPG、PNG、GIF 等)？

谢谢

Answer 1

通过

检查时剪贴板内容的mime类型

.isDataFlavorAvailable(DataFlavor.imageFlavor)

是image/x-java-image (但是 OS vendors do not need to follow MIME types for clipboards )。

我发现了两种从剪贴板获取图像并将其写入文件的方法:

1. 使用这篇博文中的辅助方法:The nightmares of getting images from the Mac OS X clipboard using Java .

   Clipboard clip = Toolkit.getDefaultToolkit().getSystemClipboard()
   
   ImageIcon IMG = new ImageIcon((BufferedImage)    
   clip.getData(DataFlavor.imageFlavor));
   BufferedImage bImage = getBufferedImage(IMG.getImage());
   ImageIO.write(bImage, "png", new File("/tmp/test.png"));
   

   getBufferedImage 方法如下所示:

   public static BufferedImage getBufferedImage(Image img) {
       if (img == null) {
           return null;
       }
       int w = img.getWidth(null);
       int h = img.getHeight(null);
       // draw original image to thumbnail image object and 
       // scale it to the new size on-the-fly 
       BufferedImage bufimg = new BufferedImage(w, h, 
           BufferedImage.TYPE_INT_RGB);
       Graphics2D g2 = bufimg.createGraphics();
       g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION,
           RenderingHints.VALUE_INTERPOLATION_BILINEAR);
       g2.drawImage(img, 0, 0, w, h, null);
       g2.dispose();
       return bufimg;
   }
   

2. 通过可转让。请注意，这在 OS X 上运行但会生成正确大小的空图像:

   Clipboard clip = Toolkit.getDefaultToolkit().getSystemClipboard()
   Transferable content =
       clip.getContents(null);
   BufferedImage img = (BufferedImage) content.getTransferData(
       DataFlavor.imageFlavor);
   ImageIO.write(img, "png", new File("/tmp/test.png"));