Practice›Java Fundamentals›Module 7. Inheritance & Polymorphism›7.4 Polymorphism

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7.4 Polymorphism — count by description

Total: 0 / 3 pts

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

Task

Fill in countDescribing so that it returns how many animals have the given word inside their describe() text.

For two dogs and one cat, searching for "dog", the program prints 2.

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);
    }

    @Override
    public String describe() {
        return getName() + " is a dog";
    }
}

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

    @Override
    public String describe() {
        return getName() + " is a cat";
    }
}

public class Main {

    public static int countDescribing(Animal[] animals, String word) {
        // count the animals whose describe() contains the word

    }

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

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