Sorting colors by the name of the color
I like your approach with mapping function, but sorting alphabetically the collection of javafx.scene.paint.Color objects can be done a little bit easier:

    final String[] colors = {"AQUA", "LAWNGREEN", "LIGHTBLUE", "CYAN", "CHOCOLATE", "GREEN",
            "RED", "YELLOW", "GAINSBORO", "YELLOWGREEN"};

    Stream.of(colors).sorted().map(color -&gt; Color.web(color)).forEach(System.out::println);


as you can see the algorithm quite simple:


Sort the string array
Map string to Color object using API method