default implementations

interface Jumper {
    default void jump() {
        System.out.println("Jumper jump!");
    }
}

interface Tracer {
    default void jump() {
        System.out.println("Tracer jump!");
    }
}

class App implements Jumper, Tracer {

    public App() {
    }

    public static void main(String args[]) {
        App myApp = new App();
        myApp.jump();
    }
}