Practice›Java Fundamentals›Module 7. Inheritance & Polymorphism›7.5 Type checks and casting

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7.5 Type checks and casting — fetch from the dogs

Total: 0 / 3 pts

Practice mode — check each part and get hints as you go.

Task

Fill in allFetches so that it returns the fetch() text of every dog in the array, one per line. Cats are skipped — they have no such method.

The program prints two lines: Rex fetches the ball and Bo fetches the ball.

Check before casting: a cat cast to Dog would crash the program.

Your solution

class Animal {
    private String name;

    public Animal(String name) {
        this.name = name;
    }

    public String getName() {
        return name;
    }

    public String describe() {
        return name + " is an animal";
    }
}

class Dog extends Animal {
    public Dog(String name) {
        super(name);
    }

    public String fetch() {
        return getName() + " fetches the ball";
    }
}

class Cat extends Animal {
    public Cat(String name) {
        super(name);
    }
}

public class Main {

    public static String allFetches(Animal[] zoo) {
        // join fetch() of every dog, one per line

    }

    public static void main(String[] args) {
        Animal[] zoo = { new Dog("Rex"), new Cat("Kit"), new Dog("Bo") };
        System.out.println(allFetches(zoo));
    }
}

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