Question

Abstract Cart class

import java.util.ArrayList;
import java.util.HashMap;
/**
* The Abstract Cart class represents a user's cart. Items of Type T can be added
* or removed from the cart. A hashmap is used to keep track of the number of items
* that have been added to the cart example 2 apples or 4 shirts.
* @author Your friendly CS Profs
* @param -Type of items that will be placed in the Cart.
*/
public abstract class AbstractCart {

   protected HashMap cart;
  
   public AbstractCart() {
       this.cart = new HashMap();
   }
  
   /**
   * Calculates the total value of items in the cart.
   * @return total (double)
   */
   public abstract double calculateTotal();
  
   /**
   * Add an item of type T to the Cart (HashMap: The product is the key
   * and the value is the count).
   * If product doesn't exist in the cart add it and set count to one.
   * Otherwise increment the value.
   * @param item
   * @return boolean
   */
   public void addItem(T item) {
//fill in
   }
  
   /**
   * Adds every item in the Arraylist of Type T or any subclass of T.
   * @param items: An array of items
   * @return true if items have been currently added.
   */
   public void addItems(ArrayList items) {
         
   }
  
   /**
   * Removes an item of type T from the list.
   * If the only one item, we remove that item.
   * If item count is greater than one decrement the count.
   * If you are able to remove the item then return true.
   * If the item doesn't exist return false.
   * @param item
   * @return true
   * in the list.
   */
   public boolean removeItem(T item) {
   //fill in
       return true;
   }
  
  
   /**
   * Removes all of the item of items of Type T or any subclass of T from the cart.
   * @param item
   * @return true if items have been successfully remove.
   */
   public void removeItems(ArrayList items) {
       //fill in
   }
  
   /**
   * Check to see if the cart contains an item.
   * @param item
   * @return true if cart contains the item. Returns False otherwize
   */
   public boolean contains(T item) {
       return cart.containsKey(item);
   }
  

  
}

AmazonCart

public class AmazonCart extends AbstractCart {

   @Override
   /**
   * Calculate the total of all the items in the cart include tax.
   * @return total
   */

   public double calculateTotal() {
       double total = 0.0;
       for(AmazonProduct item : this.cart.keySet()) {
           int itemCount = this.cart.get(item);
           total += (item.getPrice() + item.calcTax())*itemCount;
       }
       return total;
   }

}

AmazonCartTest

import static org.junit.Assert.*;

import java.util.ArrayList;

import org.junit.Test;

public class AmazonCartTest {

   @Test
   public void testAddingItemToCard() {
       Milk m = new Milk(2.5, "Lactose Free", false);
       AmazonCart amazonCart = new AmazonCart();
       amazonCart.addItem(m);
       if(amazonCart.contains(m) != true) {
           fail("Error AmazonCart-Line-13: Items not currently added to cart");
       }
   }
  
   @Test
   public void testCalculateTotal() {
       Milk m = new Milk(3, "Lactose Free", true);
       DVD d = new DVD(10, "Black Panther", true);
       Shirt s = new Shirt(100, "Versace", false);
       AmazonCart amazonCart = new AmazonCart();
       amazonCart.addItem(m);
       amazonCart.addItem(d);
       amazonCart.addItem(s);
       assert(amazonCart.calculateTotal() == 120.33);  
   }
  
   @Test
   public void testAddingDupplicates() {
       Milk m = new Milk(3, "Lactose Free", true);
       DVD d = new DVD(10, "Black Panther", true);
       Shirt s = new Shirt(100, "Versace", false);
       AmazonCart amazonCart = new AmazonCart();
       amazonCart.addItem(m);
       amazonCart.addItem(m);
       amazonCart.addItem(d);
       amazonCart.addItem(d);
       amazonCart.addItem(s);
       amazonCart.addItem(s);
       assert(amazonCart.calculateTotal() == 240.66);  
   }
  
   @Test
   public void testRemovingItem() {
       Milk m = new Milk(3, "Lactose Free", true);
       DVD d = new DVD(10, "Black Panther", true);
       Shirt s = new Shirt(100, "Versace", false);
       AmazonCart amazonCart = new AmazonCart();
       amazonCart.addItem(m);
       amazonCart.removeItem(m);
       amazonCart.addItem(d);
       amazonCart.addItem(s);
       amazonCart.addItem(s);
       assert(amazonCart.calculateTotal() == 224.3);  
   }
  
   @Test
   public void testRemovingItem2() {
       Milk m = new Milk(3, "Lactose Free", true);
       DVD d = new DVD(10, "Black Panther", true);
       Shirt s = new Shirt(100, "Versace", false);
       AmazonCart amazonCart = new AmazonCart();
       amazonCart.addItem(m);
       amazonCart.removeItem(m);
       assert(amazonCart.removeItem(d) == false);
       amazonCart.addItem(d);
       amazonCart.addItem(s);
       amazonCart.addItem(s);
       assert(amazonCart.calculateTotal() == 224.3);  
   }
  
   @Test
   public void testRemovingItem3() {
       Milk m = new Milk(3, "Lactose Free", true);
       DVD d = new DVD(10, "Black Panther", true);
       Shirt s = new Shirt(100, "Versace", false);
       AmazonCart amazonCart = new AmazonCart();
       amazonCart.addItem(m);
       amazonCart.addItem(m);
       amazonCart.removeItem(m);
       amazonCart.removeItem(m);
       assert(amazonCart.removeItem(d) == false);
       amazonCart.addItem(d);
       amazonCart.addItem(s);
       amazonCart.addItem(s);
       assert(amazonCart.calculateTotal() == 224.3);  
   }
  
  
   @Test
   public void testAddingArrayListOfItems() {
       ArrayList mArray = new ArrayList<>();
       Milk m1 = new Milk(3, "Lactose Free", true);
       Milk m2 = new Milk(2, "Whole Milk", true);
       Milk m3 = new Milk(9.5, "Goats Milk", true);
       mArray.add(m1);
       mArray.add(m2);
       mArray.add(m3);
       AmazonCart amazonCart = new AmazonCart();
       amazonCart.addItems(mArray);
   }

  
   @Test
   public void testRemovingArrayListOfItems() {
       ArrayList mArray = new ArrayList<>();
       Milk m1 = new Milk(3, "Lactose Free", true);
       Milk m2 = new Milk(2, "Whole Milk", true);
       Milk m3 = new Milk(9.5, "Goats Milk", true);
       mArray.add(m1);
       mArray.add(m2);
       mArray.add(m3);
       AmazonCart amazonCart = new AmazonCart();
       amazonCart.addItems(mArray);
       amazonCart.removeItems(mArray);
       assert(amazonCart.calculateTotal() == 0);
   }
}

Answer 1

import java.util.ArrayList;
import java.util.HashMap;
/**
* The Abstract Cart class represents a user's cart. Items of Type T can be added
* or removed from the cart. A hashmap is used to keep track of the number of items
* that have been added to the cart example 2 apples or 4 shirts.
* @author Your friendly CS Profs
 * @param <T>
* @param -Type of items that will be placed in the Cart.
*/
//public 
abstract class AbstractCart<T> {

   protected HashMap cart;
  
   public AbstractCart() {
       this.cart = new HashMap();
   }
  
   /**
   * Calculates the total value of items in the cart.
   * @return total (double)
   */
   public abstract double calculateTotal();
  
   /**
   * Add an item of type T to the Cart (HashMap: The product is the key
   * and the value is the count).
   * If product doesn't exist in the cart add it and set count to one.
   * Otherwise increment the value.
   * @param item
   * @return boolean
   */
   public void addItem(T item) {
//fill in
           int count=1;
           if(cart.containsKey(item))
           {
                   count+=cart.get(item);
                   
           }
           cart.put(item, count);
   }
  
   /**
   * Adds every item in the Arraylist of Type T or any subclass of T.
   * @param items: An array of items
   * @return true if items have been currently added.
   */
   public void addItems(ArrayList items) {
         
           for (int i=0;i<items.size();i++)
           {
                   addItem((T)items.get(i));
           }
   }
  
   /**
   * Removes an item of type T from the list.
   * If the only one item, we remove that item.
   * If item count is greater than one decrement the count.
   * If you are able to remove the item then return true.
   * If the item doesn't exist return false.
 * @param <T>
   * @param item
   * @return true
   * in the list.
   */
   public  boolean removeItem(T item) {
   //fill in
          T temp= (T) cart.remove(item);
          if(temp==null) // if item is not available
                  return false;
       return true;
   }
  
  
   /**
   * Removes all of the item of items of Type T or any subclass of T from the cart.
   * @param item
   * @return true if items have been successfully remove.
   */
   public void removeItems(ArrayList items) {
           
           for (int i=0;i<items.size();i++)
           {
                   removeItem((T)items.get(i));
           }
   }
  
   /**
   * Check to see if the cart contains an item.
   * @param item
   * @return true if cart contains the item. Returns False otherwize
   */
   public boolean contains(T item) {
       return cart.containsKey(item);
   }


  
}