加强了这么多天，运用集合知识，搞个购物商场 - 黑马程序员技术交流社区

public class Product{
private String no;
private String name;
private double price; //单价
public Product(){}
public Product(String no,String name,double price){
this.no = no;
this.name = name;
this.price = price;
}
public void setNo(String no){
this.no = no;
}
public String getNo(){
return no;
}
public void setName(String name){
this.name = name;
}
public String getName(){
return name;
}
public void setPrice(double price){
this.price = price;
}
public double getPrice(){
return price;
}
public boolean equals(Object obj){
if(this==obj) return true;
if(obj instanceof Product){
Product product = (Product)obj;
if(product.getNo().equals(this.getNo())){
return true;
}
}
return false;
}
public int hashCode(){
return (no!=null)?no.hashCode():0;
}
public String toString(){
//return "Product [no="+no+",name="+name+",price="+price+"]";
return name;
}
}

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public class Customer{
//属性
private String name;
private ShoppingCart cart;
//构造方法
public Customer(){}
public Customer(String name){ //在创建Customer对象的时候分配购物车对象
this.name = name;
this.cart = new ShoppingCart();
}
//setter and getter
public void setName(String name){
this.name = name;
}
public String getName(){
return name;
}
public void setCart(ShoppingCart cart){
this.cart = cart;
}
public ShoppingCart getCart(){
return cart;
}
//equals
public boolean equals(Object o){
if(this==o){
return true;
}
if(o instanceof Customer){
Customer customer = (Customer)o;
if((customer.getName().equals(this.getName()))){
return true;
}
}
return false;
}
//hashCode
public int hashcode(){
return name.hashCode();
}
//toString
public String toString(){
// Customer[name=sun]
return "Customer[name=" + this.getName() + "]";
}
}

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import java.util.*;
public class ShoppingCart {
private Map<Product,Integer> productsMap ;
private double totalPrice;
public ShoppingCart() {
this.productsMap = new HashMap<Product,Integer>();
}
public Map<Product, Integer> getProductsMap() {
return productsMap;
}
public void setProductsMap(Map<Product, Integer> productsMap) {
this.productsMap = productsMap;
}
public double getTotalPrice() {
return totalPrice;
}
public void setTotalPrice(double totalPrice) {
this.totalPrice = totalPrice;
}
//清空购物车
public void clear(){
productsMap.clear(); //清空集合
totalPrice = 0.0; //总价归零
}
//向购物车中添加一个商品
public void add(Product p){
if(!productsMap.containsKey(p)){
productsMap.put(p,1);
}else{
productsMap.put(p,productsMap.get(p).intValue()+1);
}
this.setTotalPrice(this.getTotalPrice()+ p.getPrice());
System.out.println("成功添加1个"+p);
}
public void add(Product p,int count){
if(!productsMap.containsKey(p)){
productsMap.put(p,count);
}else{
productsMap.put(p, productsMap.get(p) + count);
}
this.setTotalPrice(this.getTotalPrice()+ p.getPrice()*count);
System.out.println("成功添加"+count+"个"+p);
}
//删除一个商品
public void remove(Product p){
if(!productsMap.containsKey(p)){
System.out.println("购物车中没有" + p);
return;
}
if(productsMap.get(p)==1){
productsMap.remove(p); //删除一个条目
}else{
productsMap.put(p,productsMap.get(p).intValue()-1);
}
System.out.println("成功删除1个" + p + ",该购物车中"+p+"剩余"+ productsMap.get(p) +"个");
this.setTotalPrice(this.getTotalPrice()-p.getPrice());
}
//删除多个商品
public void remove(Product p,int count){
if(!productsMap.containsKey(p)){
System.out.println("购物车中没有" + p);
return;
}
Integer productCount = productsMap.get(p); //获取p商品的数量
if(productCount<count){
System.out.println("购物车中一共有"+productCount+"个"+p+",您却要删除"+count+"个.这是不行的");
return;
}
if(count==productCount){
productsMap.remove(p);
}else{
productsMap.put(p,productCount-count);
}
System.out.println("成功删除"+count+"个" + p + ",该购物车中"+p+"剩余"+ productsMap.get(p) +"个");
this.setTotalPrice(this.getTotalPrice()- p.getPrice()*count);
}
//显示购物车中的明细(遍历Map)
public void printProductList(){
if(productsMap.size()==0){
System.out.println("购物车中没有商品");
return;
}
Set<Product> keys = productsMap.keySet();
System.out.println("购物车明细:");
for(Product k:keys){
System.out.println("\t" + k + "" + productsMap.get(k) +"个");
}
System.out.println("购物车总价是:" + this.getTotalPrice());
}
}

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import java.util.HashMap;
import java.util.Map;
public class SuperMarket{
private Map<Product,Integer> productsMap;
public SuperMarket(Map<Product,Integer> productsMap) {
super();
this.productsMap = productsMap;
}
public Map<Product, Integer> getProductsMap() {
return productsMap;
}
public void setProductsMap(Map<Product, Integer> productsMap) {
this.productsMap = productsMap;
}
}

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import java.util.*;
public class Test{
public static void main(String[] args){
//0.准备货物
Product p1 = new Product("001","西瓜",5.1);
Product p2 = new Product("002","冬瓜",6.2);
Product p3 = new Product("003","南瓜",7.3);
Product p4 = new Product("004","北瓜",8.4);
Product p5 = new Product("005","香瓜",5.5);
Product p6 = new Product("006","哈密瓜",5.2);
Product p7 = new Product("007","黄瓜",10.3);
Product p8 = new Product("008","丝瓜",8.56);
Map<Product,Integer> productsMap = new HashMap<Product,Integer>();
productsMap.put(p1,3);
productsMap.put(p2,10);
productsMap.put(p3,4);
productsMap.put(p4,11);
productsMap.put(p5,5);
productsMap.put(p6,12);
productsMap.put(p7,6);
productsMap.put(p8,13);
//1.创建超市
SuperMarket sm = new SuperMarket(productsMap);
//2.创建一个顾客
Customer c = new Customer("张三");
ShoppingCart cart = c.getCart();
//3.添加1商品
cart.add(p1);
cart.add(p2);
cart.add(p3);
cart.add(p4);
cart.add(p5);
cart.add(p6);
cart.add(p7);
cart.printProductList();
//4.添加多个商品
cart.add(p1,2);
cart.add(p8,10);
cart.printProductList();
//5.删除1个商品
cart.remove(p8);
cart.printProductList();
//6.删除多个商品
cart.remove(p8,8);
cart.printProductList();
//7.清空购物车
cart.clear();
cart.printProductList();
}
}

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