Quelle: lynda.com

package org.example.java8;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import org.example.java8.model.Person;

public class InstanceMethodReference {

public static void main(String args[]){
InstanceMethodReference mainClass = new InstanceMethodReference();
mainClass.sortData();
}

public void sortData() {

List<Person> people = new ArrayList<>();

people.add(new Person(„Joe“, 48));
people.add(new Person(„Mary“, 30));
people.add(new Person(„Mike“, 73));

//Class :: method references static Mathod
Collections.sort(people, this :: compareAges);
people.forEach(p -> System.out.println(p) );
}

public int compareAges(Person p1, Person p2) {
Integer age1 = p1.getAge();
return age1.compareTo(p2.getAge());
}

}