JAVA

please explain with comments

Use the same Java time/local date library as used in the code below

1) Modify the Book and all sub-classes of the Book class constructors to throw a generic InvalidDateException when any of the following Publish dates are entered:

if the publish date is in the future (1 point)

if year is before 1200 (1 point)

if month is out of range (1 point)

if day is out of range according to the month (1 point)

if day falls on the weekend (1 point) (books arent published on weekends)

The exception should have a message with the book details and a short description of the problem (2 points).

2) When an exception is encountered, the Test class should print out the error message and continue as normal with the following books. (2 points: each test date is worth 0.25 point)

Test this by using the following dates:

Date: 2018, 11, 30

Date: 2020, 8, 4

Date: 1996, 2, 29

Date: 2010, 13, 9

Date: 2003, 1, 18

Date: 1999, 2, 30

Date: 1165, 12, 1

Date: 2015, 7, 8

Test.java

// Java core packages

import java.text.DecimalFormat;

import java.time.LocalDate;

// Java extension packages

import javax.swing.JOptionPane;

public class Test {

// test book hierarchy

public static void main(String args[]) {

Book book; // superclass reference

String output = "";

Novel novel = new Novel("Harry Potter", "J.K Rowling", 20.0, LocalDate.of(1992, 3, 26));

EducationBook educationbook = new EducationBook("My Maths 3", "James Jones", 15.6, 180654203, 4,

LocalDate.of(1913, 3, 26));

Classic classic = new Classic("The Great Gatsby", "F. Scott Fitzgerald", 35.0, LocalDate.of(1800, 3, 26));

DecimalFormat precision2 = new DecimalFormat("0.00");

// book reference to a novel

book = novel;

try {

output += book.toString() + " costs $" + precision2.format(book.cost()) + " " + novel.toString()

+ " costs $" + precision2.format(novel.cost()) + " ";

// book reference to a educationbook

book = educationbook;

output += book.toString() + " costs $" + precision2.format(book.cost()) + " " + educationbook.toString()

+ " costs $" + precision2.format(educationbook.cost()) + " ";

// book reference to a Classic

book = classic;

output += book.toString() + " costs $" + precision2.format(book.cost()) + " " + classic.toString()

+ " costs $" + precision2.format(classic.cost()) + " ";

} catch (Exception e) {

System.out.println(e.getMessage());

}

Book books[] = new Book[5];

books[0] = novel;

books[1] = educationbook;

books[2] = classic;

EducationBook educationbook1 = new EducationBook("My Maths 4", "James Jones", 15.6, 180654203, -4,

LocalDate.of(1913, 3, 26));

Classic classic2 = new Classic("The Greatest Harry", "F. SNEwewcott Fitzgerald", 35.0,

LocalDate.of(2018, 3, 26));

books[3] = educationbook1;

books[4] = classic2;

double totalCost = 0;

for (int i = 0; i < books.length; i++) {

try {

if (books[i] instanceof Classic) {

if (books[i].getPublishDate().compareTo(LocalDate.of(books[i].getPublishDate().getYear() - 50,

books[i].getPublishDate().getMonth(), books[i].getPublishDate().getDayOfMonth())) > 0) {

totalCost = totalCost + (books[i].cost()*0.35 + books[i].cost());

} else {

totalCost = totalCost + books[i].cost();

}

} else {

if (books[i].getPublishDate().compareTo(LocalDate.of(books[i].getPublishDate().getYear() - 5,

books[i].getPublishDate().getMonth(), books[i].getPublishDate().getDayOfMonth())) > 0) {

totalCost = totalCost + (books[i].cost()*0.12 + books[i].cost());

} else {

totalCost = totalCost + books[i].cost();

}

}

output = output + "Book : "+(i+1)+books[i]+" , cost : "+books[i].cost() + " ";

}catch(Exception e) {

output = output + books[i].toString()+" Cost Error: "+e.getMessage() + " ";

}

}

output = output + "Total Cost : "+totalCost;

JOptionPane.showMessageDialog(null, output, "Demonstrating Polymorphism", JOptionPane.INFORMATION_MESSAGE);

System.exit(0);

}

} // end class Test

Book.java

import java.time.LocalDate;

// Abstract base class Book.

public abstract class Book {

private String bookTitle;

private String bookAuthor;

private LocalDate publishDate;

private static int bookId = 0;

private int id;

// constructor

public Book(String title, String author, LocalDate pubDate) {

bookTitle = title;

bookAuthor = author;

publishDate = pubDate;

bookId++;

id = bookId;

}

// get bookTitle

public String getbookTitle() {

return bookTitle;

}

// get bookAuthor

public String getbookAuthor() {

return bookAuthor;

}

public int getId() {

return id;

}

public String toString() {

return id + " " + bookTitle + " " + bookAuthor + " "+ publishDate.toString();

}

public LocalDate getPublishDate() {

return publishDate;

}

public abstract double cost() throws Exception;

}

Novel.java

import java.time.LocalDate;

// Novel class derived from Book1.

public final class Novel extends Book {

private double bookCost;

// constructor for class Novel

public Novel(String title, String author, double cost, LocalDate pubDate) {

super(title, author, pubDate); // call superclass constructor

setBookCost(cost);

}

// set Novel's cost

public void setBookCost(double cost) {

bookCost = cost;

}

// get Novel's cost

public double cost() throws Exception {

if(bookCost < 0) {

throw new Exception("Total Book Cost cannot be negative.");

}

return bookCost;

}

// get String representation of book details

public String toString() {

return "Novel: " + super.toString();

}

} // end class Novel

Classic.java

import java.time.LocalDate;

// Definition of class Classic

public final class Classic extends Book {

private double bookCost; // cost of the book

// constructor for class Classic

public Classic(String title, String author, double cost, LocalDate pubDate) {

super(title, author, pubDate); // call superclass constructor

setBookCost(cost);

}

// Set the cost of the book

public void setBookCost(double cost) {

bookCost = cost;

}

// Get the Classic book's cost

public double cost() throws Exception {

if(bookCost < 0) {

throw new Exception("Total Book Cost cannot be negative.");

}

return bookCost;

}

public String toString() {

return "Classic: " + super.toString();

}

}

EducationBook.java

import java.time.LocalDate;

// EducationBook class derived from Book

public final class EducationBook extends Book {

private double bookCost; // cost of the book

private int bookIsbn; // the unique identifier of the education book

private int quantity; // number of this book required

// constructor for class EducationBook

public EducationBook(String title, String author, double cost, int isbn, int quantity,LocalDate pubDate) {

super(title, author,pubDate); // call superclass constructor

setBookCost(cost);

setIsbn(isbn);

setQuantity(quantity);

}

// set EducationBook's cost

public void setBookCost(double cost) {

bookCost = cost;

}

// set EducationBook's isbn

public void setIsbn(int isbn) {

bookIsbn = (isbn > 0 ? isbn : 0);

}

// set EducationBook's quantity sold

public void setQuantity(int totalSold) {

quantity = totalSold;

}

// determine EducationBook's total cost

public double cost() throws Exception {

if(bookCost * quantity < 0) {

throw new Exception("Total Book Cost cannot be negative.");

}

return bookCost * quantity;

}

// get String representation of EducationBook's details

public String toString() {

return "Education Book: " + super.toString();

}

} // end class EducationBook