Java: An Introduction to Problem Solving and Programming (7th Edition)
7th Edition
ISBN: 9780133766264
Author: Walter Savitch
Publisher: PEARSON
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Chapter 8, Problem 14E
Explanation of Solution
Definition of the interface “DiscountPolicy”:
Definition of the “DiscountPolicy” interface is given below:
- • Declare the “computeDiscount” method along with the two parameters “count” and “itemCost”...
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This example asks you to write an interface. Then define three classes that implement this interface. 1) Create an interface Discount Policy. It should have a single abstract method called computeDiscount that will return the discount for the purchase of a given number of a single item. The method has two parameters, count and item Cost. This interface has no other method. 2) Define a class Bulk Discount that implements the interface Discount Policy, as de- scribed above. It should have a constructor that has two parameters, minimum and percent. It should define the method computeDiscount so that if the quantity purchased of an item is more than minimum, the discount is percent percent. 3) Define another class Buy NItemsGetOneFree that implements Discount Policy as de- scribed in part 1. The class should have a constructor that has a single parameter n. In addition, the class should define the method computeDiscount so that every nth item is free. For ex- ample, the following table…
Explain the difference between the following implementations of class A.a. extending class A from class Bb. extending class A from parent abstract class Cc. class A implementing interface D
You cannot instantiate an interface but you can do so to an abstract class.
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Chapter 8 Solutions
Java: An Introduction to Problem Solving and Programming (7th Edition)
Ch. 8.1 - Prob. 1STQCh. 8.1 - Suppose the class SportsCar is a derived class of...Ch. 8.1 - Suppose the class SportsCar is a derived class of...Ch. 8.1 - Can a derived class directly access by name a...Ch. 8.1 - Can a derived class directly invoke a private...Ch. 8.1 - Prob. 6STQCh. 8.1 - Suppose s is an object of the class Student. Base...Ch. 8.2 - Give a complete definition of a class called...Ch. 8.2 - Add a constructor to the class Student that sets...Ch. 8.2 - Rewrite the definition of the method writeoutput...
Ch. 8.2 - Rewrite the definition of the method reset for the...Ch. 8.2 - Can an object be referenced by variables of...Ch. 8.2 - What is the type or types of the variable(s) that...Ch. 8.2 - Prob. 14STQCh. 8.2 - Prob. 15STQCh. 8.2 - Consider the code below, which was discussed in...Ch. 8.2 - Prob. 17STQCh. 8.3 - Prob. 18STQCh. 8.3 - Prob. 19STQCh. 8.3 - Is overloading a method name an example of...Ch. 8.3 - In the following code, will the two invocations of...Ch. 8.3 - In the following code, which definition of...Ch. 8.4 - Prob. 23STQCh. 8.4 - Prob. 24STQCh. 8.4 - Prob. 25STQCh. 8.4 - Prob. 26STQCh. 8.4 - Prob. 27STQCh. 8.4 - Prob. 28STQCh. 8.4 - Are the two definitions of the constructors given...Ch. 8.4 - The private method skipSpaces appears in the...Ch. 8.4 - Describe the implementation of the method drawHere...Ch. 8.4 - Is the following valid if ShapeBaSe is defined as...Ch. 8.4 - Prob. 33STQCh. 8.5 - Prob. 34STQCh. 8.5 - What is the difference between what you can do in...Ch. 8.5 - Prob. 36STQCh. 8 - Consider a program that will keep track of the...Ch. 8 - Implement your base class for the hierarchy from...Ch. 8 - Draw a hierarchy for the components you might find...Ch. 8 - Suppose we want to implement a drawing program...Ch. 8 - Create a class Square derived from DrawableShape,...Ch. 8 - Create a class SchoolKid that is the base class...Ch. 8 - Derive a class ExaggeratingKid from SchoolKid, as...Ch. 8 - Create an abstract class PayCalculator that has an...Ch. 8 - Derive a class RegularPay from PayCalculator, as...Ch. 8 - Create an abstract class DiscountPolicy. It should...Ch. 8 - Derive a class BulkDiscount from DiscountPolicy,...Ch. 8 - Derive a class BuyNItemsGetOneFree from...Ch. 8 - Prob. 13ECh. 8 - Prob. 14ECh. 8 - Create an interface MessageEncoder that has a...Ch. 8 - Create a class SubstitutionCipher that implements...Ch. 8 - Create a class ShuffleCipher that implements the...Ch. 8 - Define a class named Employee whose objects are...Ch. 8 - Define a class named Doctor whose objects are...Ch. 8 - Create a base class called Vehicle that has the...Ch. 8 - Create a new class called Dog that is derived from...Ch. 8 - Define a class called Diamond that is derived from...Ch. 8 - Prob. 2PPCh. 8 - Prob. 3PPCh. 8 - Prob. 4PPCh. 8 - Create an interface MessageDecoder that has a...Ch. 8 - For this Programming Project, start with...Ch. 8 - Modify the Student class in Listing 8.2 so that it...Ch. 8 - Prob. 8PPCh. 8 - Prob. 9PPCh. 8 - Prob. 10PP
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