public static ImmutableSet<HttpUrl> allSubPaths(String url) {
    return allSubPaths(HttpUrl.parse(url));
  }
@Test
  public void allSubPaths_whenMultipleSubPathsWithTrailingSlash_returnsExpectedUrl() {
    assertThat(allSubPaths("http://localhost/a/b/c/"))
        .containsExactly(
            HttpUrl.parse("http://localhost/"),
            HttpUrl.parse("http://localhost/a/"),
            HttpUrl.parse("http://localhost/a/b/"),
            HttpUrl.parse("http://localhost/a/b/c/"));
  }