GcsResourceId implements ResourceId { @Override public @Nullable String getFilename() { if (gcsPath.getNameCount() <= 1) { return null; } else { GcsPath gcsFilename = gcsPath.getFileName(); return gcsFilename == null ? null : gcsFilename.toString(); } } private  GcsResourceId(GcsPath gcsPath); @Override GcsResourceId resolve(String other, ResolveOptions resolveOptions); @Override GcsResourceId getCurrentDirectory(); @Override boolean isDirectory(); @Override String getScheme(); @Override @Nullable String getFilename(); @Override String toString(); @Override boolean equals(@Nullable Object obj); @Override int hashCode();  }
@Test public void testGetFilename() { assertNull(toResourceIdentifier("gs: assertEquals("abc", toResourceIdentifier("gs: assertEquals("abc", toResourceIdentifier("gs: assertEquals("xyz.txt", toResourceIdentifier("gs: }