java实现网上购物车程序

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; 
  } 
 
} 

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; 
  } 
   
} 

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; 
  } 
} 

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()); 
 
  } 
 
}