library management system.TXT

import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;

public class LibraryManagementSystem {
    private Map<String, Integer> bookInventory;

    public LibraryManagementSystem() {
        bookInventory = new HashMap<>();
    }

    public void addBook(String bookTitle, int quantity) {
        if (bookInventory.containsKey(bookTitle)) {
            int currentQuantity = bookInventory.get(bookTitle);
            bookInventory.put(bookTitle, currentQuantity + quantity);
        } else {
            bookInventory.put(bookTitle, quantity);
        }
        System.out.println("Book(s) added successfully!");
    }

    public void borrowBook(String bookTitle) {
        if (bookInventory.containsKey(bookTitle)) {
            int quantity = bookInventory.get(bookTitle);
            if (quantity > 0) {
                bookInventory.put(bookTitle, quantity - 1);
                System.out.println("You have borrowed \"" + bookTitle + "\".");
            } else {
                System.out.println("Sorry, the book \"" + bookTitle + "\" is currently out of stock.");
            }
        } else {
            System.out.println("Sorry, the book \"" + bookTitle + "\" is not available in the library.");
        }
    }

    public void displayInventory() {
        if (bookInventory.isEmpty()) {
            System.out.println("The library inventory is empty.");
        } else {
            System.out.println("Library Inventory:");
            for (Map.Entry<String, Integer> entry : bookInventory.entrySet()) {
                System.out.println(entry.getKey() + " - Quantity: " + entry.getValue());
            }
        }
    }

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        LibraryManagementSystem library = new LibraryManagementSystem();

        while (true) {
            System.out.println("\n1. Add Book\n2. Borrow Book\n3. Display Inventory\n4. Exit");
            System.out.print("Enter your choice: ");
            int choice = scanner.nextInt();
            scanner.nextLine(); // Consume newline character

            switch (choice) {
                case 1:
                    System.out.print("Enter book title: ");
                    String title = scanner.nextLine();
                    System.out.print("Enter quantity: ");
                    int quantity = scanner.nextInt();
                    scanner.nextLine(); // Consume newline character
                    library.addBook(title, quantity);
                    break;
                case 2:
                    System.out.print("Enter book title to borrow: ");
                    String bookToBorrow = scanner.nextLine();
                    library.borrowBook(bookToBorrow);
                    break;
                case 3:
                    library.displayInventory();
                    break;
                case 4:
                    System.out.println("Exiting...");
                    System.exit(0);
                default:
                    System.out.println("Invalid choice. Please enter a number between 1 and 4.");
            }
        }
    }
}