Listing a directory on the class path when it’s in a Jar archive

Today I was revisiting an old memory game that I wrote almost seven years ago and I must admit that I was partly horrified by the code I have written back in the days. So I started to change small parts of it. For example I was loading a set of images from a directory on the class path, by generating the name of the image, like “card1.jpg”, “card2.jpg” and getting these via getClass().getResource(name). Now, as I was changing some images, and files happened to be “.jpg” and others “.png”, my old name-generator code failed. Not a good solution, I thought, and planned to load all files from a directory that would just contain card images – didn’t work as expected though, but I found a solution on the net, which I had to change a bit to make it work for me. Here’s the result that I’d like to share.