Chapter 2, Problem 4R

Explanation of Solution

Flawed method implementation:

Let us make the assumption that, in the code fragment 1.5 in the textbook the following instance variable “balance” is changed to private visibility.

//Create a main class

public class CreditCard

{

  //Declare the instance variable

  private double balance;

}

Program:

The following code is the subclass PredatoryCreditcard extended from CreditCard class. While changing the instance variable “balance” to private visibility in main class CreditCard, the following method leads to an error:

//Create a sub class PredatoryCreditCard

public class PredatoryCreditCard extends CreditCard

{

  // Override the charge()method from superclass

  public boolean charge(double price)

  {

//Call inherited method

boolean isSuccess = super...