Re:String.hashCode() is plenty unique
by rurban on Saturday August 11, 2018 @11:09AM
(#17739938)
There's a huge math error in the article, coming to complete wrong solutions in the second case, long strings. The probability of the 2nd case is 1.4, so the outcome of 1 collision is no surprise at all, and thus you cannot praise the quality of the Java hash function this way.
What he should have praised instead is the Java hash table, which is the only one of all major programming languages, which is fast and secure. All others are mostly slow, and insecure. Java chose a fast hash and a secure collision strategy, counting collisions and switching to a tree on attacks. Most others chose a random seed and a slow hash function, which are still DOS unsafe whilst being 10x slower. Pure security theatre.
What he should have praised instead is the Java hash table, which is the only one of all major programming languages, which is fast and secure. All others are mostly slow, and insecure. Java chose a fast hash and a secure collision strategy, counting collisions and switching to a tree on attacks. Most others chose a random seed and a slow hash function, which are still DOS unsafe whilst being 10x slower. Pure security theatre.