Question

I am trying to read an image that resides somewhere on the web from my Java program. So far I have successfully loaded an image by using the following code.

URL url = new URL("http://www.google.com/images/nav_logo4.png");
Image img = Toolkit.getDefaultToolkit().getImage(url);

What I want to know is why this code (which is the first i tried) does not work:

BufferedImage img = ImageIO.read(new File("http://www.google.com/images/nav_logo4.png"));

This would have the benefit of giving me a BufferedImage. Also, how can I make the above code block until the image is loaded? I know I can use an ImageObserver, but is there a simpler way?

When I try the second option, I get this exception:

javax.imageio.IIOException: Can't read input file!

Answer 1

A File cannot refer to a URL.

Although I haven’t tried it, there appears to be a ImageIO.read(URL) method, which can take an URL as the input as an URL object.

I would presume it would be called as follows:

ImageIO.read(new URL("http://url/to/my/image.png"));