Having a Multimap sorted on keys only in Java

Question

I would like to have a c.g.c.c.Multimap that is sorted based on keys only. The values shouldn\'t be sorted. I\'ve tried to build something with guava\'s T

Answer 1

How about this:

    public static Multimap indexOnScore(Iterable i) {
        Multimap m = Multimaps.index(i, myObjectToScore());

        Multimap sortedKeys = Multimaps.newMultimap(
                Maps.>newTreeMap(),
                new Supplier>() {
                    @Override
                    public Collection get() {
                        return Lists.newArrayList(); // Or a Set if appropriate
                    }
                }
        );

        sortedKeys.putAll(m);

        return sortedKeys;
    }

There would be the overhead of creating two separate Multimaps in this case, though.