ImmutableSetMultimap<K, V> to Map<K, ImmutableSet<V>>

[oliviercailloux]

There’s Multimaps.asMap to transform a SetMultimap<K, V> to a Map<K, Set<V>>, but there’s no Multimaps.asMap to transform an ImmutableSetMultimap<K, V> to a Map<K, ImmutableSet<V>>, it seems.

Have you considered adding this method? Is it already available somehow?

Currently I copy the content into a new ImmutableSetMultimap, which seems unnecessary: Multimaps.asMap(myImmutableSetMultimap).entrySet().stream().collect(ImmutableMap.toImmutableMap((e) -> e.getKey(), (e) -> ImmutableSet.copyOf(e.getValue())))

[cpovirk]

We talked about this at least once. The main complication I recall is that it's not source-compatible: A call to asMap(immutableSetMultimap) would change return types as you've indicated, and the new type might not work where the old does. It's still a possibility -- maybe under another method name? -- we're just not sure.