Images will not work in a .jar file

Question

When a .jar of an application is created, the images in the application no longer appear. An example of our code for loading images is: ImageIcon placeHolder = new ImageIcon(src\Cards\hidden.png);

We have no idea why this is happening. The application runs as expected if we do not compress it to a .jar; as a .jar, the images simply disappear. We also tried using URLs instead of ImageIcons, but that just causes the program not to run at all.

Any ideas?

EDIT: We are putting the image files into our .jar file in the correct paths, so that's not the problem.

Answer 1

You should load resources from the classpath as such:

 InputStream is = Thread.currentThread().getContextClassLoader().getResourceAsStream("Cards/hidden.png")

This of course assumes that when you create the JAR, you are actually putting the image files into it.

There is also a method for getting the resource as a URL.

Answer 2

Question: Does the folder src exist in the jar?

Tip: You can open .jar with any unpacking program which supports ZIP to see its contents.

Answer: The way you reference the resource is incorrect, you should do something like getClass().getClassLoader().getResource("Cards/hidden.png") instead.

Answer 3

I asked the same question a while back. You should find your answers here.

Answer 4

Check the API for the constructor you're calling. The string you pass in is a file path - when the resources are packaged in a JAR, there is no file on the filesystem containing the image, so you can't use this constructor any more.

Instead you'd need to load the resources from a stream, using the classloader, and pull them into a byte array:

byte[] buffer = new byte[IMAGE_MAX_SIZE];
InputStream imageStream = getClassLoader().getResourceAsStream("src\Cards\hidden.png");
imageStream.read(buffer, 0, IMAGE_MAX_SIZE);
ImageIcon placeHolder = new ImageIcon(buffer);

Needs more exception and edge-case handling, of course, but that's the gist of it.