fastutil ConcurrentMap

Is it on the roadmap to add ConcurrentMap implementations? It would be nice to have an atomic putIfAbsent() (something less heavyweight than SynchronizedMap).

Aug 15 '17 18:08 dmolesUC

Well, putIfAbsent has been already implemented and if you synchronize a fastutil map it will be atomic, too...

On August 15, 2017 8:14:00 PM GMT+02:00, David Moles [email protected] wrote:

Is it on the roadmap to add ConcurrentMap implementations? It would be nice to have an atomic putIfAbsent().

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Aug 15 '17 21:08 vigna

The difference between fully synchronizing the map and having a concurrent map is (as far as I know) that the synchronized map usually gives a stronger atomicity than required. A concurrent hash map for example might lock each bucket individually or use read-write-locks compared to always locking the whole map.

Bottom line: Definitely possible to do, but a lot of work (testing atomicity is a real pain ...). One definitely could "fastutilize" the ConcurrentMap interface (this shouldn't be too difficult) and then do the same for the reference implementations.