Solution Review: Displaying Message Using Inheritance

class Animal {
    
    private int age;
    private String name;
    void set_data(int a, String b) {
        
        age = a;
        name = b;
    }
    public String getName() {
        return name;
    }
    public int getAge() {
        return age;
    }
}
class Zebra extends Animal {
    String message_zebra(String str) {
        str = "The zebra named " + getName() + " is " + getAge() + " years old. The zebra comes from Africa";
        return str;
    }
}
class Dolphin extends Animal {
    String message_dolphin(String str) {
        str = "The dolphin named " + getName() + " is " + getAge() + " years old. The dolphin comes from New Zealand";
        return str;
    }
}