public boolean supportsFileAttributeView(Class<? extends FileAttributeView> type) {
    return providersByViewType.containsKey(type);
  }
@Test
  public void testSupportsFileAttributeView() {
    assertThat(service.supportsFileAttributeView(BasicFileAttributeView.class)).isTrue();
    assertThat(service.supportsFileAttributeView(TestAttributeView.class)).isTrue();
    assertThat(service.supportsFileAttributeView(PosixFileAttributeView.class)).isFalse();
  }