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See Dev.java for updated tutorials taking advantage of the latest releases.
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Answers to Questions and Exercises: Inheritance

Questions

Question 1: Consider the following two classes:

public class ClassA {
 public void methodOne(int i) {
 }
 public void methodTwo(int i) {
 }
 public static void methodThree(int i) {
 }
 public static void methodFour(int i) {
 }
}
public class ClassB extends ClassA {
 public static void methodOne(int i) {
 }
 public void methodTwo(int i) {
 }
 public void methodThree(int i) {
 }
 public static void methodFour(int i) {
 }
}

Question 1a: Which method overrides a method in the superclass?
Answer 1a: methodTwo

Question 1b: Which method hides a method in the superclass?
Answer 1b: methodFour

Question 1c: What do the other methods do?
Answer 1c: They cause compile-time errors.

Question 2: Consider the Card, Deck, and DisplayDeck classes you wrote in the previous exercise. What Object methods should each of these classes override?
Answer 2: Card and Deck should override equals, hashCode, and toString.

Exercises

Exercise 1: Write the implementations for the methods that you answered in question 2.
Answer 1: See Card2.