How to solve java.lang.IllegalArgumentException: Width (-1) and height (-1) cannot be <= 0?

Question

I've been spending the last hours trying to solve the stack trace below. With major research on here SO and also through Google, I understand the exception can mean several things:

• the program can't find the requested images with the provided path;

• the images are being rendered after the width and the height are generated, reason why it equals 0...

Am I missing something? I can't figure out how to solve this...

Stack

Exception in thread "main" java.lang.IllegalArgumentException: Width (-1) and height (-1) cannot be <= 0 at java.awt.image.DirectColorModel.createCompatibleWritableRaster(DirectColorModel.java:1016) at java.awt.image.BufferedImage.(BufferedImage.java:331) at tp6.Interface.toBufferedImage(Interface.java:157) at tp6.Interface.(Interface.java:36) at tp6.Interface.main(Interface.java:171)

tp6.Interface.toBufferedImage(Interface.java:157):

public BufferedImage toBufferedImage(Image image) {

        if( image instanceof BufferedImage ) {

                return( (BufferedImage)image );
        } else {

                image = new ImageIcon(image).getImage();

                BufferedImage bufferedImage = new BufferedImage(
                                                      image.getWidth(null),
                                                      image.getHeight(null),
                                                      BufferedImage.TYPE_INT_RGB );
                Graphics g = bufferedImage.createGraphics();
                g.drawImage(image,0,0,null);
                g.dispose();
                return( bufferedImage );
        }
}

tp6.Interface.(Interface.java:36)

//IMAGE JPANEL
Image map=new ImageIcon("images/main.gif").getImage();
    Image digi=new ImageIcon("images/digits.gif").getImage();
    BufferedImage mapmodifiable= toBufferedImage(map);
    BufferedImage digits= toBufferedImage(digi);

tp6.Interface.main(Interface.java:171)

public static void main(String[] args)
    {
        Window windowintro = new Window( 440, 400, 1);
        //INTERFACE GRAPHIC
        Interface graphic=new Interface();

        graphic.addWindowListener(new WindowAdapter() {
                        @Override
            public void windowClosing(WindowEvent evt) {
                System.exit(0);
            }
        });
    }

Answer 1

The reason for the exception has already been explained, Image methods getWidth(null) and getHeight(null) both return -1 when the image dimensions are not (yet) known. This is implemented so, because the old Image API in Java is asynchronous and loads image resources off the current thread. As you write, it could also happen because the image is not found.

However, as you want to use your images as BufferedImages (presumably because you want to modify them at some stage), it's better and easier to just load them using the more recent synchronous ImageIO API. In most cases, the code will be clearer and easier to understand, and more importantly; you'll get error messages right away if the image can't be found/loaded.

So, instead of:

Image map = new ImageIcon("images/main.gif").getImage();
BufferedImage mapmodifiable = toBufferedImage(map);

You can simply do:

BufferedImage mapmodifiable = ImageIO.read(new File("images/main.gif"));

---

PS: It is possible to convert an Image to a BufferedImage like you do in your toBufferedImage method, and using ImageIcon.getImage(..) should ensure the image was preloaded (ImageIcon internally uses a MediaTracker for preloading). However, as I say above, the old Image API is not very good at error feedback, so most likely the problem is that your image isn't found.