1 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。2
3 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。4
5 商品类：6 [java] view plain copy7
8 public classProduct {9 private int productId;//商品编号
10 private String productName;//商品名称
11 private String category;//商品分类
12 private double price;//单价
13
14 public Product() {//无参构造
15 super();16 }17
18 public Product(intproductId, String productName, String category,19 doubleprice) {20 super();21 this.productId =productId;22 this.productName =productName;23 this.category =category;24 this.price =price;25 }26
27 publicString toString() {28 return "Product [productId=" + productId + ", productName="
29 + productName + ", category=" + category + ", price=" +price30 + "]";31 }32
33 public intgetProductId() {34 returnproductId;35 }36
37 public void setProductId(intproductId) {38 this.productId =productId;39 }40
41 publicString getProductName() {42 returnproductName;43 }44
45 public voidsetProductName(String productName) {46 this.productName =productName;47 }48
49 publicString getCategory() {50 returncategory;51 }52
53 public voidsetCategory(String category) {54 this.category =category;55 }56
57 public doublegetPrice() {58 returnprice;59 }60
61 public void setPrice(doubleprice) {62 this.price =price;63 }64
65 }66
67 商品条目信息类：68 [java] view plain copy69
70 public classProductItem {71 private Product product;//购买的商品
72 private int count;//商品数量
73 public double totalMoney(){//小计
74 double price=product.getPrice();//获取商品单价
75 return price*count;76 }77
78 publicProductItem() {79 super();80 }81
82 public ProductItem(Product product, intcount) {83 super();84 this.product =product;85 this.count =count;86 }87
88 publicProduct getProduct() {89 returnproduct;90 }91 public voidsetProduct(Product product) {92 this.product =product;93 }94 public intgetCount() {95 returncount;96 }97 public void setCount(intcount) {98 this.count =count;99 }100
101 }102
103
104 购物车类：105 [java] view plain copy106
107 importjava.util.Collection;108 importjava.util.Iterator;109 importjava.util.LinkedHashMap;110 importjava.util.Map;111 public class ShoppingCart {//购物车112 //key：商品编号 value:商品条目
113 private Map map=new LinkedHashMap();114
115 public void addProduct(Product p){//添加商品
116 int productId=p.getProductId();117 if(map.containsKey(productId)){118 ProductItem productItem=map.get(productId);119 productItem.setCount(productItem.getCount()+1);120 }else{121 map.put(productId, new ProductItem(p,1));122 }123 }124 public void showAll(){//查看订单信息
125 Collection productItems =map.values();126 Iterator iterator =productItems.iterator();127 while(iterator.hasNext()){128 ProductItem productItem =iterator.next();129 Product product =productItem.getProduct();130 System.out.println("商品编号："+product.getProductId()+",商品名称："
131 +product.getProductName()+",单价："+product.getPrice()+",数量："+productItem.getCount()132 +",小计："+productItem.totalMoney());133 }134 }135 public boolean deleteProduct(int productId){//删除商品
136 if(map.containsKey(productId)){137 map.remove(productId);138 return true;139 }140 return false;141 }142 public boolean modifyProduct(int productId,int count){//修改
143 if(map.containsKey(productId)){144 if(count>=1){145 ProductItem productItem =map.get(productId);146 productItem.setCount(count);147 return true;148 }else if(count==0){//删除该商品
149 deleteProduct(productId);150 return true;151 }152 }153 return false;154 }155
156 public void clearCart(){//清空购物车
157 map.clear();158 }159
160 public double totalAllMoney(){//商品总钱数
161 double total=0;162 Collection productItems =map.values();163 Iterator iterator =productItems.iterator();164 while(iterator.hasNext()){165 ProductItem productItem =iterator.next();166 double money=productItem.totalMoney();167 total+=money;168 }169 returntotal;170 }171 }172
173
174 测试类：175 [java] view plain copy176
177 public classShoppingCartTest {178
179 public static voidmain(String[] args) {180 ShoppingCart cart=newShoppingCart();181 Product p1=new Product(101,"华硕笔记本","笔记本",4599);182 Product p2=new Product(102,"苹果","水果",5.9);183 Product p3=new Product(103,"彩电","家电",2799);184 Product p4=new Product(104,"秋裤","服装",128);185 Product p5=new Product(105,"华为手机","手机",2998);186 Product p6=new Product(101,"华硕笔记本","笔记本",4599);//测试买两件商品的情况
187 cart.addProduct(p1);188 cart.addProduct(p2);189 cart.addProduct(p3);190 cart.addProduct(p4);191 cart.addProduct(p5);192 cart.addProduct(p6);193 cart.showAll();194 System.out.println("############");195 boolean flag=cart.deleteProduct(p2.getProductId());196 if(flag){197 System.out.println("商品编号为："+p2.getProductId()+"的商品删除成功！");198 }else{199 System.out.println("删除失败");200 }201 cart.showAll();202 System.out.println("############");203 boolean flag2=cart.modifyProduct(p3.getProductId(), 2);204 if(flag2){205 System.out.println("商品编号为："+p3.getProductId()+"的商品修改成功！");206 }else{207 System.out.println("修改失败");208 }209 cart.showAll();210
211 //cart.clearCart();212 //cart.showAll();
213 System.out.println("商品总价钱为："+cart.totalAllMoney());214
215 }216
217 }