Comparator

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Revision as of 18:36, 26 March 2018 by Ovidiu (talk | contribs)
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Internal

Overview

Concise Sorting

Java 8 List has a sort() method that accepts a java.util.Comparator.

java.util.Comparator is a functional interface, so we can provide a lambda expression instead.

java.util.Comparator comes with static methods that build Comparator instances, so if compare apples by weight, we can write this:

List<Apple> apples = ...
apples.sort(Comparator.comparing(a -> a.getWeight()));

The last form can be compacted even further using method references:

List<Apple> apples = ...
apples.sort(Comparator.comparing(Apple::getWeight));