迷你项目练习题6超市与购物车

你的名字 2021-09-25 07:34 312阅读 0赞

### 文章目录 ###

*  题目
 *  Product商品类
 *  CartItem类 购物项类
 *  Shop超市类
 *  Cart购物车类
 *  Test测试类

# 题目 #

模拟实现用户购买商品的功能，使用数组模拟商品列表，当购买的商品不存在或者商品库存为0时，抛出自定义异常。用户购买某一个商品时，对异常进行处理，并对库存进行改变。  
并实现添加商品到购物车,购物车列表,从购物车删除商品,清空购物车

# Product商品类 #

/** * 商品类 */
    public class Product { 
        private int id;
        private String name;
        private double price;
        private int countProduct;
        //有参构造
        public Product(int id,String name, double price,int countProduct) { 
            this.id = id;
            this.name = name;
            this.price = price;
            this.countProduct = countProduct;
        }
        //Getter&Setter
        public String getName() { 
            return name;
        }
        public void setName(String name) { 
            this.name = name;
        }
        public double getPrice() { 
            return price;
        }
        public void setPrice(double price) { 
            this.price = price;
        }
        public int getId() { 
            return id;
        }
        public void setId(int id) { 
            this.id = id;
        }
        public int getCountProduct() { 
            return countProduct;
        }
    
        public void setCountProduct(int countProduct) { 
            this.countProduct = countProduct;
        }
    }

# CartItem类 购物项类 #

/** * 购物项类 */
    public class CartItem { 
        /* 产品 数量 小计 */
        private Product product;
        private int count;
        private double subTotal;
        //有参构造
        public CartItem(Product product, int count) { 
            this.product = product;
            this.count = count;
        }
        //Getter & Setter
        public Product getProduct() { 
            return product;
        }
    
        public void setProduct(Product product) { 
            this.product = product;
        }
    
        public int getCount() { 
            return count;
        }
    
        public void setCount(int count) { 
            this.count = count;
        }
    
        public double getSubTotal() { 
            return product.getPrice()*count;
        }
    
        public void setSubTotal(double subTotal) { 
            this.subTotal = subTotal;
        }
    }

# Shop超市类 #

public class Shop { 
        //商品数组
        private Product[] products;
        private int length = 5;
        //构造器
        public Shop() { 
            products = new Product[length];
            //产品对象
            products[0] = new Product(1001,"巧克力", 10, 1000);
            products[1]= new Product(1002,"方便面", 2, 1000);
            products[2]= new Product(1003,"矿泉水", 1, 5000);
            products[3] = new Product(1004,"冰红茶", 5, 1000);
            products[4] = new Product(1005,"冰激凌", 1, 1000);
        }
    
        public Product[] getProducts() { 
            return products;
        }
        public void print(){ 
            for (int i = 0; i < products.length; i++) { 
                System.out.print("编号:"+products[i].getId());
                System.out.print(" 名称:"+products[i].getName());
                System.out.print(" 数量:"+products[i].getCountProduct());
                System.out.println(" 单价:"+products[i].getPrice());
            }
        }
    }

# Cart购物车类 #

import java.util.HashMap;
    import java.util.Map;
    
    /** * 购物车类 */
    public class Cart { 
        //存储商品的集合
        private Map<Integer,CartItem> map;
        //总价格
        private double total;
        private Shop shop;
        //构造器
        public Cart(Shop shop) { 
            map = new HashMap<>();
            this.shop = shop;
        }
        //Getter & Setter
        public Map<Integer, CartItem> getMap() { 
            return map;
        }
    
        public void setMap(Map<Integer, CartItem> map) { 
            this.map = map;
        }
    
        public double getTotal() { 
            return total;
        }
        //向购物车中添加商品的方法
        public void add(Integer id,int count) { 
            CartItem cartItem = map.get(id);
            //判断商品编号有没有找到
            boolean flag = false;
            for (int i = 0; i < shop.getProducts().length; i++) { 
                if (id == shop.getProducts()[i].getId()) { 
                    flag = true;
                    if(cartItem == null){ 
                        map.put(id, new CartItem(shop.getProducts()[i], count));
                        shop.getProducts()[i].setCountProduct(shop.getProducts()[i].getCountProduct() - count);
                    }else { 
                        cartItem.setCount(cartItem.getCount() + count);
                       shop.getProducts()[i].setCountProduct(shop.getProducts()[i].getCountProduct() - count);
                    }
                }
            }
            if(!flag){ 
                System.out.println("没有该商品编号");
            }
        }
        //购物车删除商品(连同数量一起删除)
        public void remove(Integer id){ 
            CartItem cartItem = map.get(id);
            if(map.get(id) == null){ 
                System.out.println("没有该商品");
            }else { 
                cartItem.getProduct().setCountProduct(cartItem.getProduct().getCountProduct() + cartItem.getCount());
                map.remove(id);
            }
        }
        //购物车减少某件商品的数量
        public void remove(Integer id,int count){ 
            CartItem cartItem = map.get(id);
            if(cartItem ==null){ 
                System.out.println("没有该商品");
            }else { 
                cartItem.getProduct().setCountProduct(cartItem.getProduct().getCountProduct() + count);
                cartItem.setCount(cartItem.getCount() -count);
            }
        }
        //清空购物车
        public void remove(){ 
            for (Integer integer : map.keySet()) { 
                map.get(integer).getProduct().setCountProduct(map.get(integer).getCount() + map.get(integer).getProduct().getCountProduct());
            }
            map.clear();
            total = 0;
    
        }
        //打印所有商品的方法
        public void print(){ 
            if(map.size() == 0){ 
                System.out.println("你的购物车是空的");
            }
            for (Integer integer : map.keySet()) { 
                System.out.print("编号:"+map.get(integer).getProduct().getId());
                System.out.print(" 名称:"+map.get(integer).getProduct().getName());
                System.out.print(" 数量:"+map.get(integer).getCount());
                System.out.println(" 小计:"+map.get(integer).getSubTotal());
            }
    
        }
    }

# Test测试类 #

import java.util.Scanner;
    
    /** * 测试类 */
    public class Test { 
        public static void main(String[] args) { 
            //Scanner类对象
            Scanner sc = new Scanner(System.in);
            //创建超市类对象
            Shop shop = new Shop();
            //创建购物车对象
            Cart cart = new Cart(shop);
            while (true) { 
                System.out.println("=================================");
                System.out.println("请选择要执行的功能");
                System.out.println("1.查看商品列表");
                System.out.println("2.向购物车中添加商品");
                System.out.println("3.移除购物车的某种商品");
                System.out.println("4.减少购物车种某种商品的数量");
                System.out.println("5.查看购物车");
                System.out.println("6.清空购物车");
                System.out.println("0.退出程序");
                int select = sc.nextInt();
                switch (select) { 
                    case 1:
                        shop.print();break;
                    case 2:
                    //商品列表
                    shop.print();
                    System.out.println("请输入你要添加的商品编号:");
                    int id = sc.nextInt();
                    System.out.println("请输入你要添加的商品数量");
                    int count = sc.nextInt();
                    cart.add(id, count);
                    break;
                    case 3:
                        System.out.println("请输入要删除的商品的编号:");
                        int idRemove1 = sc.nextInt();
                        cart.remove(idRemove1);
                        break;
                    case 4:
                        System.out.println("请输入要减少数量的商品的编号:");
                        int idRemove2 = sc.nextInt();
                        System.out.println("请输入要减少的数量:");
                        int countRemove = sc.nextInt();
                        cart.remove(idRemove2,countRemove);
                        break;
                    case 5:
                        cart.print();break;
                    case 6:
                        cart.remove();break;
                    case 0 :
                        System.out.println("欢迎您的下次光临");
                        System.exit(0);
                        break;
                    default:
                        System.out.println("你输入的数字不对,请重试");break;
                }
            }
        }
    }