RFR  Speedup construction of CopyOnWriteArraySet in special cases
jason_mehrens at hotmail.com
Tue Apr 30 12:55:22 UTC 2013
> The addAllAbsent() function has O(c.length^2) complexity, so
> construction time quickly grows with the input size.
> However, if we knew that c is a Set, we could construct the COWAS in
> linear time.
You have to be able to prove that the given Set uses the same equivalence relation as the COWAS. Otherwise, it will fall apart you pass a SortedSet with a Comparator or an identity set.
> And if the c was known to be another COWAS, we could simply clone the
> underlying CopyOnWriteArrayList.
That would be safe.
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