Ecommerce.java

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

class Product {
    private int id;
    private String name;
    private double price;

    public Product(int id, String name, double price) {
        this.id = id;
        this.name = name;
        this.price = price;
    }

    public int getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public double getPrice() {
        return price;
    }
}

class CartItem {
    private Product product;
    private int quantity;

    public CartItem(Product product, int quantity) {
        this.product = product;
        this.quantity = quantity;
    }

    public Product getProduct() {
        return product;
    }

    public int getQuantity() {
        return quantity;
    }
}

class ShoppingCart {
    private List<CartItem> items;

    public ShoppingCart() {
        this.items = new ArrayList<>();
    }

    public void addItem(CartItem item) {
        items.add(item);
    }

    public List<CartItem> getItems() {
        return items;
    }

    public double calculateTotal() {
        double total = 0;
        for (CartItem item : items) {
            total += item.getProduct().getPrice() * item.getQuantity();
        }
        return total;
    }
}

public class ECommercePlatform {
    private static List<Product> products = new ArrayList<>();
    private static ShoppingCart cart = new ShoppingCart();
    private static Scanner scanner = new Scanner(System.in);

    public static void main(String[] args) {
        initializeProducts();

        while (true) {
            System.out.println("1. Browse Products");
            System.out.println("2. Add to Cart");
            System.out.println("3. View Cart");
            System.out.println("4. Checkout");
            System.out.println("5. Exit");
            System.out.print("Choose an option: ");
            int option = scanner.nextInt();
            scanner.nextLine();  // Consume newline character
            
            switch (option) {
                case 1:
                    browseProducts();
                    break;
                case 2:
                    addToCart();
                    break;
                case 3:
                    viewCart();
                    break;
                case 4:
                    checkout();
                    break;
                case 5:
                    System.out.println("Exiting...");
                    System.exit(0);
                default:
                    System.out.println("Invalid option!");
            }
        }
    }

    private static void initializeProducts() {
        products.add(new Product(1, "Product 1", 10.0));
        products.add(new Product(2, "Product 2", 20.0));
        // Add more products here
    }

    private static void browseProducts() {
        System.out.println("Available Products:");
        for (Product product : products) {
            System.out.println(product.getId() + ". " + product.getName() + " - $" + product.getPrice());
        }
    }

    private static void addToCart() {
        System.out.print("Enter product ID: ");
        int productId = scanner.nextInt();
        scanner.nextLine();  // Consume newline character
        Product selectedProduct = null;
        for (Product product : products) {
            if (product.getId() == productId) {
                selectedProduct = product;
                break;
            }
        }
        if (selectedProduct != null) {
            System.out.print("Enter quantity: ");
            int quantity = scanner.nextInt();
            scanner.nextLine();  // Consume newline character
            cart.addItem(new CartItem(selectedProduct, quantity));
            System.out.println("Item added to cart!");
        } else {
            System.out.println("Product not found!");
        }
    }

    private static void viewCart() {
        List<CartItem> items = cart.getItems();
        if (items.isEmpty()) {
            System.out.println("Cart is empty.");
        } else {
            System.out.println("Cart:");
            for (CartItem item : items) {
                System.out.println(item.getProduct().getName() + " - Quantity: " + item.getQuantity());
            }
            System.out.println("Total: $" + cart.calculateTotal());
        }
    }

    private static void checkout() {
        System.out.println("Checkout - Total: $" + cart.calculateTotal());
        System.out.println("Thank you for shopping with us!");
        // Logic for completing the checkout process (e.g., payment, order creation, etc.) would go here
        // This is a simplified version without payment integration or order tracking
        cart = new ShoppingCart(); // Clear the cart after checkout
    }
}