docs: public <V extends BasicFileAttributeView, R extends BasicFileAttributes> TwoBuilder<V, R> attributes( String name, Class<V> viewClass, Class<R> readerClass ) {
          TwoBuilder<V, R> builder = new TwoBuilder<>( name, viewClass, readerClass, this );
          provider.add( name, viewClass, readerClass, builder.two );
          return builder;
      }