@Test public void extension() { assertThat(Resources.extension(Paths.get("file.txt"))).isEqualTo(".txt"); assertThat(Resources.extension(Paths.get("file.css.map"))).isEqualTo(".map"); assertThat(Resources.extension(Paths.get(".dotfile.ext"))).isEqualTo(".ext"); assertThat(Resources.extension(Paths.get("file"))).isEmpty(); assertThat(Resources.extension(Paths.get(".dotfile"))).isEmpty(); assertThat(Resources.extension(Paths.get("."))).isEmpty(); }