Shop.java

import java.util.ArrayList;
import java.util.Iterator;
import java.util.Scanner;

public class Shop {
    public static void main(String[] args) {
        // Create the products list
        ArrayList<Product> productList = new ArrayList<>();

        // Create and add product 1
        LanguagesString n1 = new LanguagesString()
                .setEn("RAM")
                .setDe("RAM");
        LanguagesString d1 = new LanguagesString()
                .setEn("Storage for your PC")
                .setDe("Speicher für dein PC");
        Product p1 = new Product(n1, d1, 1, 199.99);
        productList.add(p1);

        // Create and add product 2
        LanguagesString n2 = new LanguagesString()
                .setEn("CPU")
                .setDe("Prozessor");
        LanguagesString d2 = new LanguagesString()
                .setEn("The brain of your computer")
                .setDe("Das Gehirn deines Computers");
        Product p2 = new Product(n2, d2, 2, 199.99);
        productList.add(p2);

        // What language does the user want?
        Scanner input = new Scanner(System.in);
        System.out.println("Select language: \n1) English\n2) German");
        int lang = input.nextInt();
        String language;
        if (lang == 1) {
            language = "en";
        } else if (lang == 2) {
            language = "de";
        } else {
            language = "en";
        }

        // Print all the products
        Iterator it = productList.iterator();
        System.out.println("Products:");
        int listID = 0;
        // Go through all the products and print each one
        while (it.hasNext()) {
            System.out.println("ID: " + listID);
            Product currentProduct = (Product) it.next();
            System.out.println(currentProduct.toString(language));
            listID++;
        }

        // Select product to buy
        System.out.println("Add a product to the cart by entering it's ID or 'pay' to pay");
        ArrayList<Product> shoppingCart = new ArrayList<>();
        String command;
        int product;
        command = input.nextLine();
        // If no command has been set, or the command is "pay" than skip
        while (command == null || !command.equals("pay")) {
            command = input.nextLine();

            // End the loop if user entered "pay"
            if (command.equals("pay")) {
                continue;
            }

            // Get product id and add to cart
            try {
                // Check whether it can be translated into an integer
                product = Integer.parseInt(command);
            } catch (NumberFormatException e) {
                System.out.println("You can either enter 'pay' or the product id, nothing else");
                continue;
            }

            try {
                // Check whether the product exists and add it to the shopping cart
                Product addToCart = productList.get(product);
                shoppingCart.add(addToCart);
                System.out.println(addToCart.getName(language) + " was added to the cart");
            } catch (IndexOutOfBoundsException e) {
                System.out.println("This product doesn't exist");
            }
        }

        // Check whether cart is empty or not
        if (shoppingCart.isEmpty()) {
            System.out.println("You haven't bought anything");
        } else {
            Iterator itCart = shoppingCart.iterator();
            System.out.println("You bought:");
            while (itCart.hasNext()) {
                Product currentProduct = (Product) itCart.next();
                System.out.println(currentProduct.getName(language) + ": " + currentProduct.getDescription(language));
            }
        }
    }
}