java - MultiKeyMap vs. Map with Map values -

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what benefits of using multikeymap vs. using map map values in matters of performance (any maybe readability, in opinion)?

when use multy key map, single lookup done in underlying hashmap while if go using map map values have perform @ least 2 lookups find element looking for.

also note may use generics map of map-s , may specify key-s , values types, while multikeymap can not that. why using map of map-s bit "safer" in aspect.


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