Starting Out with Java: Early Objects (6th Edition)
6th Edition
ISBN: 9780134462011
Author: Tony Gaddis
Publisher: PEARSON
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Textbook Question
Chapter 9, Problem 4FTE
// Superclass
public class Vehicle
{
public abstract double getMilesPerGallon( );
(Other methods …)
}
// Subclass
public class Car extends Vehicle
{
private int mpg;
public int getMilesPerGallon();
{
return mpg;
}
(Other methods…)
}
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public abstract class Shape {
public Shape() { }
public abstract double area() ;
public String who() { return "Shape" ; }
}
public class Circle extends Shape {
private int radius ;
public Circle( int r )
{
radius = r ;
}
@Override
public double area()
{
return Math.PI * radius * radius ;
}
}
public class Square extends Shape {
private int _sideLength ;
public Square( int sideLength )
{
/* TODO question 45 */
}
@Override
public double area()
{
return _sideLength * _sideLength ;
}
}
Implement the Square constructor, and make sure it throws an exception when the input parameter is not a valid length. The input parameter must be positive to be considered valid.
What is the output of the following code?
Convert the abstract class into an interface and modify the codes in all classes that will maintain the
same output. (Rewrite the code)
What is outpout?
public class Vehicle {
public void drive(){
System.out.println("Driving vehicle");
}
public class Plane extends Vehicle {
@Override
public void drive(){
System.out.println("Flying plane");
}
public static void main(String args[]) {
Vehicle myVehicle
myVehicle.drive();
}
}
= new Plane();
syntax error
Driving vehicle
Flying plane
Flying plane
O Driving vehicle
Chapter 9 Solutions
Starting Out with Java: Early Objects (6th Edition)
Ch. 9.1 - Here is the first line of a class declaration....Ch. 9.1 - Look at the following class declarations and...Ch. 9.1 - Class B extends class A. (Class A is the...Ch. 9.2 - Prob. 9.4CPCh. 9.2 - Look at the following classes: public class Ground...Ch. 9.3 - Under what circumstances would a subclass need to...Ch. 9.3 - How can a subclass method call an overridden...Ch. 9.3 - If a method in a subclass has the same signature...Ch. 9.3 - If a method in a subclass has the same name as a...Ch. 9.3 - Prob. 9.10CP
Ch. 9.4 - When a class member is declared as protected, what...Ch. 9.4 - What is the difference between private members and...Ch. 9.4 - Why should you avoid making class members...Ch. 9.4 - Prob. 9.14CPCh. 9.4 - Why is it easy to give package access to a class...Ch. 9.6 - Look at the following class definition: public...Ch. 9.6 - When you create a class, it automatically has a...Ch. 9.7 - Recall the Rectangle and Cube classes discussed...Ch. 9.8 - Prob. 9.19CPCh. 9.8 - If a subclass extends a superclass with an...Ch. 9.8 - What is the purpose of an abstract class?Ch. 9.8 - If a class is defined as abstract, what can you...Ch. 9.9 - Prob. 9.23CPCh. 9.9 - Prob. 9.24CPCh. 9.9 - Prob. 9.25CPCh. 9.9 - Prob. 9.26CPCh. 9.9 - Prob. 9.27CPCh. 9.9 - Prob. 9.28CPCh. 9 - In an inheritance relationship, this is the...Ch. 9 - In an inheritance relationship, this is the...Ch. 9 - This key word indicates that a class inherits from...Ch. 9 - A subclass does not have access to these...Ch. 9 - This key word refers to an objects superclass. a....Ch. 9 - In a subclass constructor, a call to the...Ch. 9 - The following is an explicit call to the...Ch. 9 - A method in a subclass that has the same signature...Ch. 9 - A method in a subclass having the same name as a...Ch. 9 - These superclass members are accessible to...Ch. 9 - Prob. 11MCCh. 9 - With this type of binding, the Java Virtual...Ch. 9 - Prob. 13MCCh. 9 - Prob. 14MCCh. 9 - Prob. 15MCCh. 9 - Abstract classes cannot ___________. a. be used as...Ch. 9 - You use the __________ operator to define an...Ch. 9 - Prob. 18MCCh. 9 - Prob. 19MCCh. 9 - You can use a lambda expression to instantiate an...Ch. 9 - True or False: Constructors are not inherited.Ch. 9 - True or False: in a subclass, a call to the...Ch. 9 - True or False: If a subclass constructor does not...Ch. 9 - True or False: An object of a superclass can...Ch. 9 - True or False: The superclass constructor always...Ch. 9 - True or False: When a method is declared with the...Ch. 9 - True or False: A superclass has a member with...Ch. 9 - True or False: A superclass reference variable can...Ch. 9 - True or False: A subclass reference variable can...Ch. 9 - True or False: When a class contains an abstract...Ch. 9 - True or False: A class may only implement one...Ch. 9 - True or False: By default all members of an...Ch. 9 - // Superclass public class Vehicle { (Member...Ch. 9 - // Superclass public class Vehicle { private...Ch. 9 - // Superclass public class Vehicle { private...Ch. 9 - // Superclass public class Vehicle { public...Ch. 9 - Write the first line of the definition for a...Ch. 9 - Look at the following code, which is the first...Ch. 9 - Write the declaration for class B. The classs...Ch. 9 - Write the statement that calls a superclass...Ch. 9 - A superclass has the following method: public void...Ch. 9 - A superclass has the following abstract method:...Ch. 9 - Prob. 7AWCh. 9 - Prob. 8AWCh. 9 - Look at the following interface: public interface...Ch. 9 - Prob. 1SACh. 9 - A program uses two classes: Animal and Dog. Which...Ch. 9 - What is the superclass and what is the subclass in...Ch. 9 - What is the difference between a protected class...Ch. 9 - Can a subclass ever directly access the private...Ch. 9 - Which constructor is called first, that of the...Ch. 9 - What is the difference between overriding a...Ch. 9 - Prob. 8SACh. 9 - Prob. 9SACh. 9 - Prob. 10SACh. 9 - What is an. abstract class?Ch. 9 - Prob. 12SACh. 9 - When you instantiate an anonymous inner class, the...Ch. 9 - Prob. 14SACh. 9 - Prob. 15SACh. 9 - Employee and ProductionWorker Classes Design a...Ch. 9 - ShiftSupervisor Class In a particular factory, a...Ch. 9 - TeamLeader Class In a particular factory, a team...Ch. 9 - Essay Class Design an Essay class that extends the...Ch. 9 - Course Grades In a course, a teacher gives the...Ch. 9 - Analyzable Interface Modify the CourseGrades class...Ch. 9 - Person and Customer Classes Design a class named...Ch. 9 - PreferredCustomer Class A retail store has a...Ch. 9 - BankAccount and SavingsAccount Classes Design an...Ch. 9 - Ship, CruiseShip, and CargoShip Classes Design a...
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