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javaimagejavax.imageioico

How to get favicon.ico from a website using Java?


So I'm making an application to store shortcuts to all the user's favorite applications, acting kind of like a hub. I can have support for actual files and I have a .lnk parser for shortcuts. I thought it would be pretty good for the application to support Internet shortcuts, too. This is what I'm doing:

Suppose I'm trying to get Google's icon (http://www.google.com/favicon.ico).

  1. I start out by getting rid of the extra pages (e.g. www.google.com/anotherpage would become www.google.com.

  2. Then, I use ImageIO.read(java.net.URL) to get the Image.

The problem is that ImageIO never returns an Image when I call this method:

String trimmed = getBaseURL(page); //This removes the extra pages
Image icon = null;    
try {
    String fullURLString = trimmed + "/favicon.ico";
    URL faviconURL = new URL(fullURLString);
    icon = ImageIO.read(faviconURL);
} catch (IOException e) {
    e.printStackTrace();
}

return icon;

Now I have two questions:

  1. Does Java support the ICO format even though it is from Microsoft?
  2. Why does ImageIO fail to read from the URL?

Thank you in advance!


Solution

  • Try Image4J.

    As this quick Scala REPL session shows (paste-able as Java code):

    > net.sf.image4j.codec.ico.ICODecoder.read(new java.net.URL("http://www.google.com/favicon.ico").openStream())
    
    res1: java.util.List[java.awt.image.BufferedImage] = [BufferedImage@65712a80: type = 2 DirectColorModel: rmask=ff0000 gmask=ff00 bmask=ff amask=ff000000 IntegerInterleavedRaster: width = 16 height = 16 #Bands = 4 xOff = 0 yOff = 0 dataOffset[0] 0]
    

    UPDATE

    To answer your questions: Does Java support ICO? Doesn't seem like it:

    > javax.imageio.ImageIO.read(new java.net.URL("http://www.google.com/favicon.ico"))
    
    java.lang.IllegalArgumentException: Empty region!
    

    Why does ImageIO fail to read from the URL? Well, the URL itself seems to work for me, so you may have a proxy/firewall issue, or it could be the problem above.