Utilizing Java Object-Oriented Approach →hardMultiple ChoiceObjective-mapped

1Z0-829 Utilizing Java Object-Oriented Approach Practice Question

Exhibit

abstract class Animal {
    abstract void sound();
}
interface Pet {
    default void play() { System.out.println("Playing"); }
}
class Dog extends Animal implements Pet {
    void sound() { System.out.println("Bark"); }
}
public class Test {
    public static void main(String[] args) {
        Dog d = new Dog();
        d.sound();
        d.play();
    }
}

Refer to the exhibit. What is the result?

⚠ Common exam trap

A common mix-up: candidates think the `play()` method must be overridden in `Dog` to be called, or that the output would be only 'Bark' because they overlook the inherited method call, leading them to choose option D.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

Bark Playing

The code compiles and runs without error. The object referenced by a1 is a Dog instance. The code first calls the bark() method, which prints 'Bark' (defined in Dog). Then it calls the play() method, which is not overridden in Dog, so it invokes the inherited play() method from Animal, printing 'Playing'. Therefore, the output is 'Bark' followed by 'Playing', which matches option B.

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1Z0-829 Utilizing Java Object-Oriented Approach Practice Question

Exhibit

Why each option matters

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