Question

8.7 LAB*: Program: Online shopping cart (Part 2)

Note: Creating multiple Scanner objects for the same input stream yields unexpected behavior. Thus, good practice is to use a single Scanner object for reading input from System.in. That Scanner object can be passed as an argument to any methods that read input.

This program extends the earlier "Online shopping cart" program. (Consider first saving your earlier program).

(1) Extend the ItemToPurchase class per the following specifications:

• Private fields

• string itemDescription - Initialized in default constructor to "none"

• Parameterized constructor to assign item name, item description, item price, and item quantity (default values of 0). (1 pt)

• Public member methods

• setDescription() mutator & getDescription() accessor (2 pts)

• printItemCost() - Outputs the item name followed by the quantity, price, and subtotal

• printItemDescription() - Outputs the item name and description
  

Ex. of printItemCost() output:

Bottled Water 10 @ $1 = $10

Ex. of printItemDescription() output:

Bottled Water: Deer Park, 12 oz.

(2) Create two new files:

• ShoppingCart.java - Class definition

• ShoppingCartManager.java - Contains main() method

Build the ShoppingCart class with the following specifications. Note: Some can be method stubs (empty methods) initially, to be completed in later steps.

• Private fields

• String customerName - Initialized in default constructor to "none"

• String currentDate - Initialized in default constructor to "January 1, 2016"

• ArrayList cartItems

• Default constructor

• Parameterized constructor which takes the customer name and date as parameters (1 pt)

• Public member methods

• Outputs each item's description.

• Outputs total of objects in cart.

• If cart is empty, output this message: SHOPPING CART IS EMPTY

• Determines and returns the total cost of items in cart. Has no parameters.

• Returns quantity of all items in cart. Has no parameters.

• Modifies an item's description, price, and/or quantity. Has parameter ItemToPurchase. Does not return anything.

• If item can be found (by name) in cart, check if parameter has default values for description, price, and quantity. If not, modify item in cart.

• If item cannot be found (by name) in cart, output this message: Item not found in cart. Nothing modified.

• Removes item from cartItems array. Has a string (an item's name) parameter. Does not return anything.

• If item name cannot be found, output this message: Item not found in cart. Nothing removed.

• Adds an item to cartItems array. Has parameter ItemToPurchase. Does not return anything.

• getCustomerName() accessor (1 pt)

• getDate() accessor (1 pt)

• addItem()

• removeItem()

• modifyItem()

• getNumItemsInCart() (2 pts)

• getCostOfCart() (2 pts)

• printTotal()

• printDescriptions()

Ex. of printTotal() output:

John Doe's Shopping Cart - February 1, 2016
Number of Items: 8

Nike Romaleos 2 @ $189 = $378
Chocolate Chips 5 @ $3 = $15
Powerbeats 2 Headphones 1 @ $128 = $128

Total: $521

Ex. of printDescriptions() output:

John Doe's Shopping Cart - February 1, 2016

Item Descriptions
Nike Romaleos: Volt color, Weightlifting shoes
Chocolate Chips: Semi-sweet
Powerbeats 2 Headphones: Bluetooth headphones

(3) In main(), prompt the user for a customer's name and today's date. Output the name and date. Create an object of type ShoppingCart. (1 pt)

Ex.

Enter Customer's Name:
John Doe
Enter Today's Date:
February 1, 2016

Customer Name: John Doe
Today's Date: February 1, 2016

(4) Implement the printMenu() method. printMenu() has a ShoppingCart parameter, and outputs a menu of options to manipulate the shopping cart. Each option is represented by a single character. Build and output the menu within the method.

If the an invalid character is entered, continue to prompt for a valid choice. Hint: Implement Quit before implementing other options. Call printMenu() in the main() method. Continue to execute the menu until the user enters q to Quit. (3 pts)

Ex:

MENU
a - Add item to cart
d - Remove item from cart
c - Change item quantity
i - Output items' descriptions
o - Output shopping cart
q - Quit

Choose an option:

(5) Implement Output shopping cart menu option. (3 pts)

Ex:

OUTPUT SHOPPING CART
John Doe's Shopping Cart - February 1, 2016
Number of Items: 8

Nike Romaleos 2 @ $189 = $378
Chocolate Chips 5 @ $3 = $15
Powerbeats 2 Headphones 1 @ $128 = $128

Total: $521

(6) Implement Output item's description menu option. (2 pts)

Ex.

OUTPUT ITEMS' DESCRIPTIONS
John Doe's Shopping Cart - February 1, 2016

Item Descriptions
Nike Romaleos: Volt color, Weightlifting shoes
Chocolate Chips: Semi-sweet
Powerbeats 2 Headphones: Bluetooth headphones

(7) Implement Add item to cart menu option. (3 pts)

Ex:

ADD ITEM TO CART
Enter the item name:
Nike Romaleos
Enter the item description:
Volt color, Weightlifting shoes
Enter the item price:
189
Enter the item quantity:
2

(8) Implement Remove item menu option. (4 pts)

Ex:

REMOVE ITEM FROM CART
Enter name of item to remove:
Chocolate Chips

(9) Implement Change item quantity menu option. Hint: Make new ItemToPurchase object and use ItemToPurchase modifiers before using modifyItem() method. (5 pts)

Ex:

CHANGE ITEM QUANTITY
Enter the item name:
Nike Romaleos
Enter the new quantity:
3

Answer 1

import java.util.Scanner;
import java.util.ArrayList;
import java.lang.String;

public class ShoppingCartManager {
   
   public static Scanner scnr = new Scanner(System.in);
   
   public static void printMenu (ShoppingCart cart) {
      
      char inputChoice;
      
      System.out.println("\nMENU");
      System.out.println("a - Add item to cart");
      System.out.println("d - Remove item from cart");
      System.out.println("c - Change item quantity");
      System.out.println("i - Output items\' descriptions");
      System.out.println("o - Output shopping cart");
      System.out.println("q - Quit\n");
      
   }
   
   public static void main(String[] args) {
      
      char inputChoice;
      
      System.out.println("Enter Customer's Name:");
      String name = scnr.nextLine();
      
      System.out.println("Enter Today's Date:");
      String date = scnr.nextLine();
      
      ShoppingCart cart = new ShoppingCart(name, date);
      
      System.out.println("\nCustomer Name: " + cart.getCustomerName());
      System.out.println("Today's Date: " + cart.getDate());
      
      ItemToPurchase item = new ItemToPurchase();
      
      do {
         
         printMenu(cart);
         
         do {
            
            System.out.println("Choose an option:");
            inputChoice = scnr.next().charAt(0);
      
         } while ((inputChoice != 'a') && (inputChoice != 'o') && (inputChoice != 'i') && (inputChoice != 'd') && (inputChoice != 'c') && (inputChoice != 'q'));
         
         switch (inputChoice) {
            
            case 'q':
               break;
               
            case 'a':
               System.out.println("ADD ITEM TO CART");
               
               System.out.println("Enter the item name:");
               String itemName = scnr.next() + scnr.nextLine();
               item.setName(itemName);
               itemName = item.getName();
               
               System.out.println("Enter the item description:");
               String itemDescription = scnr.nextLine();
               item.setDescription(itemDescription);
               itemDescription = item.getDescription();
               
               System.out.println("Enter the item price:");
               int itemPrice = scnr.nextInt();
               item.setPrice(itemPrice);
               itemPrice = item.getPrice();
               
               System.out.println("Enter the item quantity:");
               int itemQuantity = scnr.nextInt();
               item.setQuantity(itemQuantity);
               itemQuantity = item.getQuantity();
               
               ItemToPurchase addItem = new ItemToPurchase(itemName, itemDescription, itemPrice, itemQuantity);
               cart.addItem(addItem);
               continue;
               
            case 'o':
               cart.outputCart();
               continue;
               
            case 'i':
               cart.printDescriptions();
               continue;
               
            case 'd':
               System.out.println("REMOVE ITEM FROM CART");
               System.out.println("Enter name of item to remove:");
               String rName = scnr.next() + scnr.nextLine();
               cart.removeItem(rName);
               continue;
               
            case 'c':
               System.out.println("CHANGE ITEM QUANTITY");
               System.out.println("Enter the item name:");
               String cName = scnr.next() + scnr.nextLine();
               System.out.println("Enter the new quantity:");
               int cQuan = scnr.nextInt();
               cart.modifyItem(item, cName, cQuan);
               continue;
               
            default:
               continue;
               
         }
         
      } while (inputChoice != 'q');
      
   }
   
}

import java.util.Scanner;
import java.util.ArrayList;
import java.lang.String;

public class ShoppingCart {
   
   //Private fields
   
   private String customerName;
   private String currentDate;
   private ArrayListcartItems = new ArrayList();
   
   //Default constructor
   
   public ShoppingCart() {
      customerName = "none";
      currentDate = "January 1, 2016";
   }
   
   public ShoppingCart(String name, String date) {
      customerName = name;
      currentDate = date;
   }
   
   //Public member methods
   
   public String getCustomerName() {
      return customerName;
   }
   
   public String getDate() {
      return currentDate;
   }
   
   public void addItem(ItemToPurchase item) {
      cartItems.add(item);
   }
   
   public void removeItem(String name) {
      
      int flag = 0;
      
      for (int i = 0; i < cartItems.size(); i++) {
         if (cartItems.get(i).getName().equals(name)) {
            cartItems.remove(i);
            flag = 1;
         }
      }
      if (flag == 0) {
         System.out.println("Item not found in cart. Nothing removed.");
      }
   }
   
   public void modifyItem(ItemToPurchase item, String name, int quantity) {
      
      int flag = 0;
      
      for (int i = 0; i < cartItems.size(); i++) {
         
         if (cartItems.get(i).getName().equals(name)) {
            
            item.setQuantity(quantity);
            System.out.println(item.getQuantity());
            
            ItemToPurchase newItem = new ItemToPurchase(name, cartItems.get(i).getDescription(), cartItems.get(i).getPrice(), quantity);
            
            cartItems.set(i, newItem);
            
            flag = 1;
            break;
         }
      }
      if (flag == 0) {
         System.out.println("Item not found in cart. Nothing modified.");
      }
   }
   
   public int getNumItemsInCart() {
      
      int numItems = 0;
      
      if (cartItems == null) {
         return numItems;
      }
      
      for (int i = 0; i < cartItems.size(); i++) {
         numItems = numItems + cartItems.get(i).getQuantity();
      }
      
      return numItems;
   }
   
   public int getCostOfCart() {
      
      if (cartItems == null) {
         return 0;
      }
      
      int totalCost = 0;
      int cost = 0;
      
      for (int i = 0; i < cartItems.size(); i++) {
         cost = (cartItems.get(i).getQuantity()) * (cartItems.get(i).getPrice());
         totalCost = totalCost + cost;
      }
      return totalCost;
   }
   
   public void printTotal() {
      
      int totalCost = getCostOfCart();
      
      if (totalCost == 0) {
         System.out.println("SHOPPING CART IS EMPTY\n");
         System.out.println("Total: $" + totalCost);
      }
      else {
         System.out.println("Total: $" + totalCost);
      }
      
   }
   
   public void printDescriptions() {
      
      System.out.println("OUTPUT ITEMS\' DESCRIPTIONS");
      
      System.out.println(getCustomerName() + "\'s Shopping Cart - " + getDate());
      
      System.out.println("\nItem Descriptions");
      
      for (int i = 0; i < cartItems.size(); i++) {
         System.out.println(cartItems.get(i).getName() + ": " + cartItems.get(i).getDescription());
      }
      
   }
   
   public void outputCart() {
      
      System.out.println("OUTPUT SHOPPING CART");
      
      System.out.println(getCustomerName() + "\'s Shopping Cart - " + getDate());
      
      System.out.println("Number of Items: " + getNumItemsInCart());
      
      for (int i = 0; i < cartItems.size(); i++) {
         if (i == 0) {
            System.out.println();
         }
         System.out.println(cartItems.get(i).getName() + " " + cartItems.get(i).getQuantity() + " @ $" + cartItems.get(i).getPrice() + " = $" + (cartItems.get(i).getPrice() * cartItems.get(i).getQuantity()));
      }
      
      System.out.println();
      
      printTotal();
      
   }
   
}

import java.util.Scanner;
import java.util.ArrayList;
import java.lang.String;

public class ItemToPurchase {
   
   private String itemName;
   private int itemPrice;
   private int itemQuantity;
   private String itemDescription;
   
   public ItemToPurchase () {
      itemName = "none";
      itemPrice = 0;
      itemQuantity = 0;
      itemDescription = "none";
   }
   
   public ItemToPurchase (String name, String description, int price, int quantity) {
      itemName = name;
      itemPrice = price;
      itemQuantity = quantity;
      itemDescription = description;
   }
   
   public void setDescription(String description) {
      itemDescription = description;
   }
   
   public String getDescription() {
      return itemDescription;
   }
   
   public void printItemCost() {
      System.out.println(itemName + " " + itemQuantity +  " @ $" + itemPrice + " = $" + (itemPrice * itemQuantity));
   }
   
   public void printItemDescription() {
      System.out.println(itemName + ": " + itemDescription);
   }
   
   public void setName(String name) {
      itemName = name;
   }
   
   public String getName() {
      return itemName;
   }
   
   public void setPrice(int price) {
      itemPrice = price;
   }
   
   public int getPrice() {
      return itemPrice;
   }
   
   public void setQuantity(int quantity) {   
      itemQuantity = quantity;
   }
   
   public int getQuantity() {
      return itemQuantity;
   }

}