Question

I am having trouble getting my ImagePanel to display when I pack it was a jar. When I run the project from Eclipse it displays just fine. here is the line that creates the ImagePanel:

ImagePanel panel = new ImagePanel(this.getClass().getClassLoader()
    .getResource("edu/luc/tictactoe/gui/resources/images/UIMM.png"));
frame.setContentPane(panel);

and here is the ImagePanel class:

@SuppressWarnings("serial")
public class ImagePanel extends JPanel {

    BufferedImage img;

    public ImagePanel(URL url) {
        super(true);
        this.setToolTipText(url.getPath());
        try {
            img = ImageIO.read(new File(url.getPath()));
            this.setPreferredSize(new Dimension(
                img.getWidth(), img.getHeight()));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    protected void paintComponent(Graphics g) {
        g.drawImage(img, 0, 0, this.getWidth(), this.getHeight(), null);
    }
}

Any suggestions?

Answer 1

img = ImageIO.read(new File(url.getPath()));  // REMOVE!

Try this instead..

img = ImageIO.read(url);

---

BTW – When things go wrong it would pay not to stumble blindly through what is happening. Better to use a debugger and examine the actual values passed, or at least use System.out.pritln() as a sanity check. E.G.

import java.net.URL;

class URLTest {

    public static void main(String[] args) throws Exception {
        URL url = new URL("jar:file:/C:/baz.jar!/COM/foo/Quux.class");
        System.out.println(url);
        System.out.println(url.getPath());
    }
}

Output

jar:file:/C:/baz.jar!/COM/foo/Quux.class
file:/C:/baz.jar!/COM/foo/Quux.class

Now tell me. Does the path even look like a file name/path?

When in doubt. Print out.