High-performance Concurrent MultiMap Java/Scala

Question

I am looking for a high-performance, concurrent, MultiMap. I have searched everywhere but I simply cannot find a solution that uses the same approach as ConcurrentHashMap (O

Answer 1

Why not wrap ConcurrentHashMap[T,ConcurrentLinkedQueue[U]] with some nice Scala-like methods (e.g. implicit conversion to Iterable or whatever it is that you need, and an update method)?