The code is not all written yet, i only covered so far the following parts:
1- add a book to the library.
2- display the books.
3- remove a book.
4- repeat the previous functions as many times as needed.
5- exit the program.
Need help in constructing Classes for my Library system
package library;
import java.util.ArrayList;
import java.util.InputMismatchException;
import java.util.Scanner;
public class Book {
public String title;
public String author;
public String publisher;
public String publicationYear;
public String status;
public String borrower;
public String borrowDate;
public String returnDate;
public String status1 = "Available";
public String status2 = "Borrowed";
public int BookChoice;
static ArrayList<String> UserList = new ArrayList<String>();
static ArrayList<Book> BookList = new ArrayList<Book>();
static int choice ;
static Scanner userInput = new Scanner(System.in);
static Scanner choiceInput = new Scanner(System.in);
/*
* Book Constructor:
*/
/**
* ===================================================================================================
* Class Methods here:
* ===================================================================================================
*/
public static void displayFirstMenu(){
System.out.println(">########################################################################");
System.out.println("> Choose one of the options below by typing the corresponding number: ");
System.out.println(">====================================================================");
System.out.println("2- Add a book to the Library.");
System.out.println("6- Blow up library.");
System.out.println("7- Back to main menu.");
System.out.println("0- Exit.");
System.out.println(">########################################################################");
System.out.println("> Enter your option here: ");
choice = choiceInput.nextInt();//User inputs a choice (integer).
}
public static void displaySecondMenu(){
System.out.println(">########################################################################");
System.out.println("> Choose one of the options below by typing the corresponding number: ");
System.out.println(">====================================================================");
System.out.println("1- Check library list.");
System.out.println("2- Add a book to the Library.");
System.out.println("3- Borrow a book.");
System.out.println("4- Return a book.");
System.out.println("5- Delete a book.");
System.out.println("6- Blow up library.");
System.out.println("7- Back to main menu.");
System.out.println("0- Exit.");
System.out.println(">########################################################################");
System.out.println("> Enter your option here: ");
choice = choiceInput.nextInt();//User inputs a choice (integer).
}
public String displayBook(){
String BookInfo = "----------------------------"+
"\nTitle:.................."+title+
"\nAuthor:................."+author+
"\nPublisher:.............."+publisher+
"\nPublicationYear:........"+publicationYear+
"\nStatus:................."+status+
"\nBorrower:..............."+borrower+
"\nDate Borrowed:.........."+borrowDate+
"\nReturn date:............"+returnDate+
"\n----------------------------";
return BookInfo;
}
public void createBook(){
System.out.println("> Enter the title of the book: ");
title = userInput.nextLine();
System.out.println("> Enter the author of the book: ");
author = userInput.nextLine();
System.out.println("> Enter the publisher of the book: ");
publisher = userInput.nextLine();
System.out.println("> Enter the publication year of the book: ");
publicationYear = userInput.nextLine();
borrower = "nobody";
borrowDate = "none";
returnDate = "none";
status = "Available";
}
public void addBook(){
Book newBook = new Book(); //create new book object with status "Available."
newBook.createBook();
BookList.add(newBook);//add the book to the BookList ArrayList.
System.out.println("---------------------------------------------------------");
System.out.println("> You have successfully added the book to the library!\n");
System.out.println("---------------------------------------------------------");
}
public void displayBookList(){
if (BookList.size() == 0){//If the library is empty, it goes back to main menu and choice.
System.out.println(">-------------------------------------------------------------");
System.out.println("> There Library is Emply! Please add a book first!\n");
System.out.println(">-------------------------------------------------------------");
Book.displayFirstMenu();//Display to main menu.
choice = choiceInput.nextInt();//Register new choice.
} else {
for (int i = 0; i < BookList.size(); i++){
System.out.printf("\n>-----------Book Index: [%s]---------------------------------\n",i+1);
System.out.println(BookList.get(i).displayBook());
System.out.println(">-------------------------------------------------------------");
}//End of For Loop.
}// End of Else Statement.
}//End of if Statement.
public void borrowBook(){
System.out.println("---------------------------------------------------------");
System.out.println("> Here are all the books registered in the library: ");
System.out.println("---------------------------------------------------------");
displayBookList();
borrowLoop1:
while(choice == 3){
System.out.println("\n\n> Choose an available book from the above list and write down it's index number: ");
BookChoice = choiceInput.nextInt()-1;//register user's book choice.
if(BookChoice > BookList.size()){
System.out.println("> The number of the book you entered is not in the list!");
choice = 7;
}else if(BookChoice <= BookList.size()){
break borrowLoop1;
}
}
borrowLoop2:
while(choice == 3){
//Check if the book to be borrowed is available.
if (BookList.get(BookChoice).status.equalsIgnoreCase(status1) && BookList.size() >= BookChoice){
//Print the borrowed book information and change the book status to borrowed.
BookList.get(BookChoice).status = "Borrowed";
System.out.printf("\n> You have chosen the following book: %s\n", BookList.get(BookChoice).displayBook());
//add the user name to the book borrower variable:
BookList.get(BookChoice).borrower = borrower;
BookList.get(BookChoice).borrowDate = "Today.";
BookList.get(BookChoice).returnDate = "In two weeks.";
System.out.println("> You have to return the book in two weeks!");
choice = 7;
break borrowLoop2;
}else if(BookList.get(BookChoice).status.equalsIgnoreCase(status2) && BookList.size() >= BookChoice){
System.out.println("> The Book you are trying to borrow is unavailable!");
choice = 7;
break borrowLoop2;
}else if(BookChoice > BookList.size()-1){
System.out.println("> The number you entered in not in the list!");
choice = 7;
break borrowLoop2;
}
}
}
public void returnBook(){
System.out.println("> Enter the Title of the book you want to return: ");
String returnBookTitle = userInput.nextLine();
int x = 0;
while (x < BookList.size()){//Search for the book by title, if it exists change it's status,
//it's borrower and borrowDate.
if (BookList.get(x).title.equalsIgnoreCase(returnBookTitle)){
BookList.get(x).status = "Available";
BookList.get(x).borrower = "none";
BookList.get(x).borrowDate = "none";
System.out.println("> You have successfully returned the book to the library!");
Book.displayFirstMenu();//Display main menu.
choice = choiceInput.nextInt();//Register new choice.
break;//if a title is found, break out of the loop and display choice menu.
}
x = x+1;
}//end of while loop.
x = 0;
while (x < BookList.size() && BookList.size() > 0){//Search for the title and if it's not in the library,
//print a warning message to the user, and register a new menu choice.
if (BookList.get(x).title.equalsIgnoreCase(returnBookTitle)){
}else{
System.out.println("> The are no books with this title in the library." +
" Please make sure the title is spelt correctly or choose to add the book " +
"to the library from the main menu. ");
Book.displayFirstMenu();//Display main menu.
choice = choiceInput.nextInt();//Register new choice.
}//End of else statement.
}//End of while loop.
Book.displayFirstMenu();//Display main menu.
choice = choiceInput.nextInt();//Register new choice.
}
public void removeBook(){
int i = 0;
System.out.println("---------------------------------------------------------");
System.out.println("> Here are all the books registered in the library: ");
System.out.println("---------------------------------------------------------");
while (i < BookList.size() && BookList.size() > 0){//show the user the list of all the books
System.out.printf("\n> Book number %s:\n%s",i+1,BookList.get(i));
i = i+1;
}//end of while loop.
System.out.println("\n\n> Choose an available book from the above list and write down it's number: ");
int BookChoice = choiceInput.nextInt()-1;//register user's book choice.
while(choice == 5){
try{
if (BookChoice > 0 && BookChoice < BookList.size() && BookList.get(BookChoice).status.equalsIgnoreCase("Available")){//Check if the book to be borrowed is available.
//Print the borrowed book information and change the book status to borrowed.
BookList.remove(BookChoice);
System.out.printf("\n> You have chosen to delete the following book: %s\n", BookList.get(BookChoice));
System.out.printf("\n> The Book %s is deleted.\n", BookList.get(BookChoice));
choice = 7;
}
}catch(InputMismatchException error){
System.out.println("<ERROR> Please enter a number of book from the list: ");
choiceInput.nextInt();
choice = 5;
}catch(IndexOutOfBoundsException error){
System.out.println("<ERROR> Please enter a number of book from the list: ");
choice = 5;
}
}
}
public void emptyLibrary(){
System.out.println("> WARNING < You have chosen to delete all books in the library! ");
System.out.println("> Are you sure?? Enter yes or no: ");
String confirmation = userInput.nextLine();
try{
if(confirmation.equalsIgnoreCase("yes")){
System.out.println("> Library is being deleted...");
BookList.clear();
System.out.println("> Library is Empty!");
choice = 7;
}
}catch(InputMismatchException error){
System.out.println("<ERROR> Make sure you spell yes or no correctrly: ");
choice = 6;
}
}
public void addUser(){
System.out.println("> Enter your name: ");
borrower = userInput.nextLine();
UserList.add(borrower); //Add the userName to the UserList arrayList.
}
public void run(){
System.out.println("@TEST@ <<< 1 >>>>");
addUser();
System.out.println("@TEST@ <<< 2 >>>>");
Book.displayFirstMenu();//Displays the main menu and ask for choice.
System.out.println("@TEST@ <<< 3- Entering main while loop...>>>>");
exit:
while(choice != 0){
try{
//Choice 1:
if(choice == 1 && BookList.size() > 0){
displayBookList();
choice = 7;
}
if(choice == 1 && BookList.size() == 0){
System.out.println("<ERROR> Library is empty! Please add a Book first!");
choice = 7;
}
//Choice 2:
if(choice == 2){
//createBook();
addBook();
displaySecondMenu();
}
//Choice 3:
if(choice == 3){
if(BookList.size() > 0){
borrowBook();
}
}
//Choice 4:
if(choice == 4){
returnBook();
}
//Choice 5:
if(choice == 5){
removeBook();
try{
if(BookList.size() > 0){
displaySecondMenu();
}
}catch(IndexOutOfBoundsException error){
System.out.println("<ERROR> The array is Empty! Please add a book first!");
choice = 7;
//break; //Test the Break statement!!!!!!!!!!!!!!!!!!!
}
}
//Choice 6:
if(choice == 6){
emptyLibrary();
}
//Choice 7:
if(choice == 7){
if(BookList.size() > 0){
displaySecondMenu();
}else if(BookList.size() == 0){
displayFirstMenu();
}
}
//Choice 0:
if(choice == 0){
break exit;
}
}catch(InputMismatchException error){
System.out.println("@TEST@ <<< 5- Breaking from main while loop... >>>>");
break exit;
}
}//end of while loop.
System.out.println("#### You have Exited the Library! ####");
}//End of run() method.
/**
* ===================================================================================================
* End of Class Methods.
* ===================================================================================================
*/
public static void main(String[] args){
System.out.println("> Welcome to the library!");
Book newBook = new Book();
newBook.run();
}//End of Main Method.
}
