@Override
  public String getScheme() {
    return scheme;
  }
@Test
  public void testGetScheme() {
    // Tests s3 paths.
    assertEquals("s3", S3ResourceId.fromUri("s3://my_bucket/tmp dir/").getScheme());

    // Tests bucket with no ending '/'.
    assertEquals("s3", S3ResourceId.fromUri("s3://my_bucket").getScheme());
  }