Shopping-cart-Programm

Habe ich gearbeitet, auf meiner shopping-cart-Programm, aber irgendwie habe ich immer Probleme mit der Eingabe itemTax in und mit dem hinzufügen neuer Artikel in den Warenkorb und ich weiß nicht, was ich falsch gemacht habe.

Klasse Item:

public class Item {

private int id;
private String name;
private double price;
private String description;
private int quantity;
private double tax;

public Item (int itemID, String itemName, double itemPrice, String itemDescription, int itemQuantity, double itemTax){
    id = itemID;
    name = itemName;
    price = itemPrice;
    description = itemDescription;
    quantity = itemQuantity;
    tax = itemTax;
}

public int getID(){
    return id;
}

public String getName(){
    return name;
}

public double getPrice(){
    return price;
}

public String getDescription(){
    return description;
}

public int getQuantity(){
    return quantity;
}

public double getTax(){
    return tax;
}

}

Klasse Cart:

import java.util.Scanner;

public class Cart {

private int itemCount;
private double totalPrice;
private static int capacity;
private static Item[] cart = new Item[capacity];

public Cart(){
    itemCount = 10;
    totalPrice = 0.0;
    capacity = 0;
}

public void add(int itemID, String itemName, double itemPrice, String itemDescription, int itemQuantity, double itemTax){
    Item item = new Item(itemID, itemName, itemPrice, itemDescription, itemQuantity, itemTax);
    totalPrice += (itemPrice * itemQuantity);
    cart[itemCount] = item;
    itemCount += 1;
    if(itemCount==capacity)
    {
        increaseSize();
    }
}

public static void remove(String itemName){
    Scanner s = new Scanner(System.in);

    for (int i = 0; i < cart.length; i++) {
        Item remove = (Item) cart.get(i);
        if (itemName.equals(remove.getName())) {
            cart.remove(i);

        }
    }
    System.out.println("\n" + "Item " + itemName + " wasn't found.");
}

private void increaseSize()
{
    Item[] item = new Item[capacity+5];
    for(int i=0; i < capacity; i++)
    {
        item[i] = cart[i];
    }
    cart = item; 
    item = null;
    capacity = cart.length;
}

public static void prLine (int itemID, String itemName, int itemQuantity, double itemPrice, double total, double itemTax) {
    System.out.printf("\n%-10.10d %30s %10.2f %10d %10.2f", itemID, itemName, itemPrice, itemQuantity, itemTax, total);
}   

public static void prTitles () {
    System.out.printf("\n%-10s 30% %10s %10s %10s %10s", "ID", "Item", "Price", "Quantity", "Tax", "Total");
}



}

Klasse Shop:

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

public class Shop {
public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    ArrayList<Item> cart = new ArrayList<Item>();

    Item item;
    int itemID;
    String itemName;
    double itemPrice;
    String itemDescription;
    int itemQuantity;
    double itemTax;
    int ch;
    String choice;

    Cart shoppingCart = new Cart();

    while (true) {
        System.out.println("Menu:");
        System.out.println("0) Exit " + "\n"
                + "1) Add item in shopping cart" + "\n"
                + "2) Remove item from shpping cart");
        ch = sc.nextInt();

        switch (ch) {
        case 0:
            System.out.println("\n" + "Good bye!");
            System.exit(0);

        case 1:
            System.out.println("Enter item ID: ");
            itemID = sc.nextInt();

            System.out.println("Enter item name: ");
            itemName = sc.next();

            System.out.println("Enter item price: ");
            itemPrice = sc.nextDouble();

            System.out.println("Enter short description of item: ");
            itemDescription = sc.next();

            System.out.println("Enter quantity: ");
            itemQuantity = sc.nextInt();

            System.out.println("Enter tax rate:");
            itemTax = sc.nextDouble();


            shoppingCart.add(itemID, itemName, itemPrice, itemDescription, itemQuantity,       itemTax);

            break;

        case 2:
            System.out.println("Enter name of the item that you would like to remove: ");
            choice = sc.next();
            shoppingCart.remove(choice);

            break;
        }

    }
}

}