Java8: HashMap to HashMap using Stream / Map-Reduce / Collector

Question

I know how to \"transform\" a simple Java List from Y -> Z, i.e.:

List x;
List y = x.stre         


        

Answer 1

The declarative and simpler solution would be :

yourMutableMap.replaceAll((key, val) -> return_value_of_bi_your_function); Nb. be aware your modifying your map state. So this may not be what you want.

Cheers to : http://www.deadcoderising.com/2017-02-14-java-8-declarative-ways-of-modifying-a-map-using-compute-merge-and-replace/