7. The Diamond Problem: Default Methods

Scenario

Java doesn't support multiple inheritance via classes. But with Java 8 default methods in interfaces, we can have a conflict. How does Java solve it?

Code Block

interface Camera {
    default void start() { System.out.println("Camera starting..."); }
}

interface GPS {
    default void start() { System.out.println("GPS starting..."); }
}

class SmartPhone implements Camera, GPS {
    @Override
    public void start() {
        // Must explicitly decide which one to call or provide new logic
        Camera.super.start();
        GPS.super.start();
        System.out.println("Phone ready!");
    }
}

public class Main {
    public static void main(String[] args) {
        new SmartPhone().start();
    }
}

Take Your Shot

Predicted Output

Type exactly what you think will be printed in the console.