Method reference in Java 8

Question

public class Car {

    private int maxSpeed;

    public Car(int maxSpeed) {
        this.maxSpeed = maxSpeed;
    }

    public int getMaxSpeed() {
        return maxS         


        

Answer 1

That is because the getMaxSpeed method is a Function.

Namely:

 Comparator java.util.Comparator.comparing(
    Function keyExtractor
)

Note

In order to reference getMaxSpeed from an instance of Car with the :: idiom, you would have to declare a Car method with signature: getMaxSpeed(Car car).