@Override
    public URL getURL() throws IOException {
        URL url = resolveURL();
        if (url == null) {
            throw new FileNotFoundException(getDescription() + " cannot be resolved to URL because it does not exist");
        }
        return url;
    }
This implementation returns a URL for the underlying class path resource,
if available.

see java.lang.ClassLoader#getResource(String)
see java.lang.Class#getResource(String)
analyzer/src/main/java/nl/basjes/parse/useragent/utils/springframework/core/io/ClassPathResource.java