:: (double colon) operator in Java 8

Question

I was exploring the Java 8 source and found this particular part of code very surprising:

//defined in IntPipeline.java
@Override
public fin         


        

Answer 1

I found this source very interesting.

In fact, it is the Lambda that turns into a Double Colon. The Double Colon is more readable. We follow those steps:

STEP1:

// We create a comparator of two persons
Comparator c = (Person p1, Person p2) -> p1.getAge().compareTo(p2.getAge());

STEP2:

// We use the interference
Comparator c = (p1, p2) -> p1.getAge().compareTo(p2.getAge());

STEP3:

// The magic using method reference
Comparator c = Comparator.comparing(Person::getAge);