List files on the classpath with guava Resources

Fixtures.java

    public static List<String> getFiles() {
        String fixturesRoot = Resources.getResource("fixtures").getPath();
        final Path fixturesRootPath = Paths.get(fixturesRoot);

        try {
            return Files.walk(fixturesRootPath)
                    .filter(Files::isRegularFile)
                    .map(path -> fixturesRootPath.relativize(path).toString())
                    .collect(Collectors.toList());
        } catch (IOException e) {
            throw new IllegalArgumentException(e);
        }
    }