Java OOP

SHORT ANSWER QUESTIONS

INHERITANCE & POLYMORPHISM 2

QUESTIONS

1-public

2-private

3-protected

4-overriding

5-@Override

6-super.toString()

7-Polymorphism

8-True

9-superclass

10-True

11-True

12-Object

13-The issue in the code above is that the datafields in the superclass Spell are set to private. So they are not accessible from other classes, even subclasses. The solution is to make them protected instead of private. See the alterations in blue below.

Superclass	Subclass
public class Spell { //only the datafields are shown protected int manaCost; protected String name; }	public class Frost extends Spell { private int damage; //only the toString() method is shown public String toString() { return name + "(" + damage + ")"; } }

14-When we want to call a method in the superclass, we can simply put super in front of it. See the solution in blue.

Superclass	Subclass
public class Enemy { //only the damage method is shown public int damage(int defense) { return damage * attack/defense; } }	public class Ghost extends Enemy { //only two methods are shown @Override public int damage(int defense) { return 2*damage * attack/defense; } public int critDamage(int defense) { return super.damage(defense) * 5; } }

15-The @Override (which is optional) forces your IDE to verify if the method below it is in fact overriding another method. In this case, it is not because it is named dmg instead of damage. We need to make the names match. See the solution in blue.

Superclass	Subclass
public class Badguy { //this is the only instance method //in the class public int damage(int defense) { return damage * attack/defense; } }	public class Boss extends Badguy { //only this method is shown @Override public int damage(int defense) { return 2*damage * attack/defense; } }