Design Book Library In Java (Object-Oriented Design)

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The class OnlineReader represents the body of the program. Book.java class contains all the properties and methods of the book. The Library.java class is responsible for creating a library that has methods that help to control the library.

import java.util.*;
public class Library {
private HashMap<Integer, Book> Books;
public Library(){
    Books = new HashMap<Integer, Book>();
}
/** This will add a new book in library */
public Boolean AddBook(Book book)
{
   if(!Books.containsKey(book.GetBookId())) {
        Books.put(book.GetBookId(), book);
        return true;
     }
   return false;
}
/**This will remove a book from library*/
public Boolean RemoveBook(int id)
{
if(Books.containsKey(id)) {
      Books.remove(id);
      return true;
}
    return false;
}
/**Get a single book from library*/
public Book GetBookFromLibrary(int id)
{
  Book book = null;
  if(!Books.containsKey(id))
  return book;
  if(Books.containsKey(id)) {
     book = Books.get(id);
    book.SetAvailability();
  }
   return book;
}
/**Get all books from library*/
public List<Book> GetAllBooksFromLibrary()
{
List<Book> books = new ArrayList<Book>();
   for(Book val: Books.values()) {
      books.add(val);
     }
   return books;
 }
}

public class Book {
    private int id;
    private String Name;
    private String Author;
    private boolean IsAvailable;
   public Book(int id, String Name, String Author)
   {
    this.id = id;
    this.Name = Name;
    this.Author = Author;
    this.IsAvailable = true;
   }
   public int GetBookId()
   {
  return id;
   }
public void SetBookId(int id)
{
  this.id = id;
}
public String GetBookName()
{
   return Name;
}
public void SetBookName(String Name)
{
  this.Name = Name;
}
public String GetAuthor()
{
  return Author;
}
public void SetAuthor(String Author)
{
  this.Author = Author;
}
public void SetAvailability()
{
  this.IsAvailable = false;
}
public String IsBookAvailable()
{
  return this.IsAvailable ? “Yes” : “No”;
}
}

import java.util.List;
public class OnlineReader {
private Library library;
private Book book;
public OnlineReader() {
 library = new Library();
}
public void DisplayAllBooksFromLibraray()
{
    List<Book> books = library.GetAllBooksFromLibrary();
     for(Book b: books) {
        PrintBookInfoOnScreen(b);
     }
}
public void DisplayBookfromLibrary(int id)
{
    Book b = library.GetBookFromLibrary(id);
    if(b!=null) {
           PrintBookInfoOnScreen(b);
     }
}
public void PrintBookInfoOnScreen(Book b)
{
  System.out.println(“Id: “+b.GetBookId()+” Name: “+b.GetBookName()+ “ Author: “+b.GetAuthor()+ “ Available: “+b.IsBookAvailable());
}
public void AddSeparator()
{
System.out.println(“ — — — — — — — — — — — — — — — — — — — — — — — — — — — — — — -”);
}
public static void main(String [] args)
 {
    OnlineReader reader = new OnlineReader();
    reader.book = new Book(1, “Book 1” , “Author 1”);
    reader.library.AddBook(reader.book);
    reader.book = new Book(2, “Book 2” , “Author 2”);
    reader.library.AddBook(reader.book);
    reader.book = new Book(3, “Book 3” , “Author 3”);
    reader.library.AddBook(reader.book);
    reader.DisplayBookfromLibrary(2);
    reader.AddSeparator();
    reader.DisplayAllBooksFromLibraray();
    reader.library.RemoveBook(3);
    reader.AddSeparator();
    reader.DisplayAllBooksFromLibraray();
    reader.AddSeparator();
 }
}

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