How should I use getResource() in Java?

Question

This question is asked in numerous places, with myriad small variations. (Such as Java - getClassLoader().getResource() driving me bonkers among others.) I still can't make it work.
Here's a code snippet:

        String clipName = "Chook.wav";
        ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
        // URL url = classLoader.getResource(clipName);
        URL url = new URL("file:///Users/chap/Documents/workspace/the1620/bin/ibm1620/" + clipName);
        ais = AudioSystem.getAudioInputStream(url);

This works -- note that I've hard-coded the path to the directory containing the clip file, which is there, and is in the same directory as my .class file. Alas, the commented-out code just returns a null value for url.

Most other posts seem to deal with getResourceAsStream(). I think I'm supposed to be using getResource(). Is that making the difference?

It just can't be this hard. Any clues?