Java Stream: find an element with a min/max value of an attribute

Question

I have a stream of objects and I would like to find the one with a maximal value of some attribute that\'s expensive to calculate.

As a specific simple example, say

Answer 1

Here's a variant using an Object[] as a tuple, not the prettiest code but concise

String coolestString = stringList
        .stream()
        .map(s -> new Object[] {s, coolnessIndex(s)})
        .max(Comparator.comparingInt(a -> (int)a[1]))
        .map(a -> (String)a[0])
        .orElse(null);