new File(getClass.getResource("/images/sprites").getPath).listFiles()

URI uri = MainApp.class.getResource("/images/sprites").toURI();
    Map<String, String> env = new HashMap<>();
    try (FileSystem zipfs = FileSystems.newFileSystem(uri, env)) {
        //Path path = zipfs.getPath("/images/icons16");
        for (Path path : zipfs.getRootDirectories()) {
            Files.list(path.resolve("/images/sprites"))
                    .forEach(p -> System.out.println("* " + p));
        }
    }