用java代码写一个简单的网上购物车程序

需求：1、写一个商品类，有商品编号、商品名称、商品分类、商品单价属性。2、写一个商品条目信息类，有商品和数量两个属性，有商品总价格方法。

3、写一个购物车类，有添加商品方法、查看订单信息，删除商品，修改商品，清空购物车，求购物车中所有商品总金额方法。4、写一个测试类，测试上述方法。

商品类：
[java] view plain copy

    public class Product {  
        private int productId;// 商品编号  
        private String productName;// 商品名称  
        private String category;// 商品分类  
        private double price;// 单价  
      
        public Product() {// 无参构造  
            super();  
        }  
      
        public Product(int productId, String productName, String category,  
                double price) {  
            super();  
            this.productId = productId;  
            this.productName = productName;  
            this.category = category;  
            this.price = price;  
        }  
      
        public String toString() {  
            return "Product [productId=" + productId + ", productName="  
                    + productName + ", category=" + category + ", price=" + price  
                    + "]";  
        }  
      
        public int getProductId() {  
            return productId;  
        }  
      
        public void setProductId(int productId) {  
            this.productId = productId;  
        }  
      
        public String getProductName() {  
            return productName;  
        }  
      
        public void setProductName(String productName) {  
            this.productName = productName;  
        }  
      
        public String getCategory() {  
            return category;  
        }  
      
        public void setCategory(String category) {  
            this.category = category;  
        }  
      
        public double getPrice() {  
            return price;  
        }  
      
        public void setPrice(double price) {  
            this.price = price;  
        }  
      
    }  

商品条目信息类：
[java] view plain copy

    public class ProductItem {  
        private Product product;//购买的商品  
        private int count;//商品数量  
        public double totalMoney(){//小计  
            double price=product.getPrice();//获取商品单价  
            return price*count;  
        }  
          
        public ProductItem() {  
            super();  
        }  
      
        public ProductItem(Product product, int count) {  
            super();  
            this.product = product;  
            this.count = count;  
        }  
      
        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;  
        }  
          
    }  


购物车类：
[java] view plain copy

    import java.util.Collection;  
    import java.util.Iterator;  
    import java.util.LinkedHashMap;  
    import java.util.Map;  
    public class ShoppingCart {//购物车  
        //key：商品编号 value:商品条目  
        private Map<Integer,ProductItem> map=new LinkedHashMap<Integer,ProductItem>();  
          
        public void addProduct(Product p){//添加商品  
            int productId=p.getProductId();  
            if(map.containsKey(productId)){  
                ProductItem productItem=map.get(productId);  
                productItem.setCount(productItem.getCount()+1);  
            }else{  
                map.put(productId, new ProductItem(p,1));  
            }  
        }  
        public void showAll(){//查看订单信息  
            Collection<ProductItem> productItems = map.values();  
            Iterator<ProductItem> iterator = productItems.iterator();  
            while(iterator.hasNext()){  
                ProductItem productItem = iterator.next();  
                Product product = productItem.getProduct();  
                System.out.println("商品编号："+product.getProductId()+",商品名称："  
                +product.getProductName()+",单价："+product.getPrice()+",数量："+productItem.getCount()  
                +",小计："+productItem.totalMoney());  
            }  
        }  
        public boolean deleteProduct(int productId){//删除商品  
            if(map.containsKey(productId)){  
                map.remove(productId);  
                return true;  
            }  
            return false;  
        }  
        public boolean modifyProduct(int productId,int count){//修改  
            if(map.containsKey(productId)){  
                if(count>=1){  
                    ProductItem productItem = map.get(productId);  
                    productItem.setCount(count);  
                    return true;  
                }else if(count==0){//删除该商品  
                    deleteProduct(productId);  
                    return true;  
                }     
            }  
            return false;  
        }  
          
        public void clearCart(){//清空购物车  
            map.clear();  
        }  
          
        public double totalAllMoney(){//商品总钱数  
            double total=0;  
            Collection<ProductItem> productItems = map.values();  
            Iterator<ProductItem> iterator = productItems.iterator();  
            while(iterator.hasNext()){  
                ProductItem productItem = iterator.next();  
                double money=productItem.totalMoney();  
                total+=money;  
            }  
            return total;  
        }  
    }  


测试类：
[java] view plain copy

        public class ShoppingCartTest {  
          
            public static void main(String[] args) {  
                ShoppingCart cart=new ShoppingCart();  
                Product p1=new Product(101,"华硕笔记本","笔记本",4599);  
                Product p2=new Product(102,"苹果","水果",5.9);  
                Product p3=new Product(103,"彩电","家电",2799);  
                Product p4=new Product(104,"秋裤","服装",128);  
                Product p5=new Product(105,"华为手机","手机",2998);  
                Product p6=new Product(101,"华硕笔记本","笔记本",4599);//测试买两件商品的情况  
                cart.addProduct(p1);  
                cart.addProduct(p2);  
                cart.addProduct(p3);  
                cart.addProduct(p4);  
                cart.addProduct(p5);  
                cart.addProduct(p6);  
                cart.showAll();  
                System.out.println("############");  
                boolean flag=cart.deleteProduct(p2.getProductId());  
                if(flag){  
                    System.out.println("商品编号为："+p2.getProductId()+"的商品删除成功！");  
                }else{  
                    System.out.println("删除失败");  
                }  
                cart.showAll();  
                System.out.println("############");  
                boolean flag2=cart.modifyProduct(p3.getProductId(), 2);  
                if(flag2){  
                    System.out.println("商品编号为："+p3.getProductId()+"的商品修改成功！");  
                }else{  
                    System.out.println("修改失败");  
                }  
                cart.showAll();  
                  
                //cart.clearCart();  
                //cart.showAll();  
                System.out.println("商品总价钱为："+cart.totalAllMoney());  
          
            }  
          
        }