I’m developing a game in Swing, where I’d like to use both audio and image assets. My issue is that, while opening the .png images works fine, opening my .mp3 file always throws a FileNotFoundException, and file.exists() returns false.

I am trying to create a side bar for a simple program that I am working on. I decided to use JRadioButtons in a group, and customize their appearance, to make the side bar appear the way I want. I customize the radio button’s appearances by creating a custom UI.