购物车模块

1.购物车中存放每条记录（不同类商品）及其购买数量的类

public class BuyItem {
     private Sku sku;
     private Integer amount = 1;
    public Sku getSku() {
        return sku;
    }
    public void setSku(Sku sku) {
        this.sku = sku;
    }
    public Integer getAmount() {
        return amount;
    }
    public void setAmount(Integer amount) {
        this.amount = amount;
    }
    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((amount == null) ? 0 : amount.hashCode());
        result = prime * result + ((sku == null) ? 0 : sku.hashCode());
        return result;
    }
    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        BuyItem other = (BuyItem) obj;
        if (sku == null) {
            if (other.sku != null)
                return false;
        } else if (!sku.getId().equals(other.sku.getId()))
            return false;
        return true;
    }
}

2.存放BuyItem的类

public class BuyCart {
     List<BuyItem> items = new ArrayList<BuyItem>();
     private Integer productId;
   //添加方法
    public void addItem(BuyItem item){
         if(items.contains(item)){
             for (BuyItem buyItem : items) {
                if(buyItem.equals(item)){
                    int result = 0;
                    if(item.getAmount()!=null && buyItem.getAmount()!=null){
                        result = item.getAmount()+buyItem.getAmount();    
                    }
                    if(buyItem.getSku().getSkuUpperLimit()>=result ){
                        buyItem.setAmount(result);
                    }else{
                        buyItem.setAmount(buyItem.getSku().getSkuUpperLimit());
                    }    
                }    
            }
         }else{
                items.add(item);
         }
     
     }
    
    /**
     * 小计 直接写在购物车中
     * @return
     */
 //获得物品个数
    @JsonIgnore //因为有返回参数在将其转为json格式时会出现异常
    public int getProductAmount(){
        int result = 0;
        for (BuyItem buyItem : items) {
            result += buyItem.getAmount();
        }
        return result;
    }
//商品金额
    @JsonIgnore
    public double getProductPrice(){
        double result = 0.0;
        for (BuyItem buyItem:items) {
            result+=buyItem.getSku().getSkuPrice()*buyItem.getAmount();
        }
        return result;
    }
    //运费
    @JsonIgnore
    public Double getFee(){
        double result = 0.0;
        if(getProductPrice()<=39){
            result = 10;
        }
        return result;
    }
    //应付金额
    @JsonIgnore
    public Double getTotalPrice(){
        return getFee()+getProductPrice();    
    }
    //清空购物车
    public void clearCart(){
        items.clear();
    }
    
    public void deleteItem(BuyItem buyItem){
        items.remove(buyItem);
    }
    
    public Integer getProductId() {
        return productId;
    }
    public void setProductId(Integer productId) {
        this.productId = productId;
    }
    public List<BuyItem> getItems() {
        return items;
    }
     
     
}

3.controller层 商品添加购物车，购买，清除购物车等

@Controller
public class CardController {
    //1.获得所有cookie，检测cookie中是否存有购物车
    //2.如果没有则new一个，有则获取到cookie中的购物车（ObjectMapper）
    //3.给buyItem中的sku和amout赋值，将buyItem加入到购物车buyCart中
    //4.将购物车存放到cookie中
    //5.装载购物车
    @Resource
    private SkuService SkuService;
    @RequestMapping(value="/shopping/buyCart.shtml") //将商品加入购物车
    public String buyCart(Integer skuId,Integer amount,Integer buyLimit,Integer productId,HttpServletRequest request,HttpServletResponse response,ModelMap model){
       ObjectMapper om = new ObjectMapper();
       om.setSerializationInclusion(Inclusion.NON_NULL);//去掉空值
       BuyCart buyCart = null;
       //获取cookie中的购物车
       Cookie []cookies = request.getCookies();
       if(cookies!=null&&cookies.length>0){
           for (Cookie cookie : cookies) {
                if(Constants.BUYCART_COOKIE.equals(cookie.getName())){//判断是否为购物车
                     String value = cookie.getValue();
                     //把json转化成对象
                     try {
                       buyCart = om.readValue(value,BuyCart.class);
                    } catch (Exception e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } 
                     break;
                }
            }
       }
      if(null==buyCart){
          buyCart = new BuyCart();
      }
       
      if(null!=skuId){
          Sku sku = new Sku();
          sku.setId(skuId);
          if(buyLimit!=null){
              sku.setSkuUpperLimit(buyLimit); 
          }
          BuyItem buyItem = new BuyItem();
          buyItem.setSku(sku);
          buyItem.setAmount(amount);
          buyCart.addItem(buyItem);
          if(null!=productId){
              buyCart.setProductId(productId);
          }
          
          StringWriter stringWriter = new StringWriter();
          try {
             om.writeValue(stringWriter, buyCart); //将对象转化为json
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
          Cookie cookie = new Cookie(Constants.BUYCART_COOKIE, stringWriter.toString());//购物车加入到cookie中
          //所有只能存一个购物车
          cookie.setPath("/");
          cookie.setMaxAge(60*60*24);
          response.addCookie(cookie);
      }
         //装载购物车 装满
       List<BuyItem> items = buyCart.getItems();
       for (BuyItem buyItem : items) {
          Sku sku = SkuService.getSkuByKey(buyItem.getSku().getId());
          buyItem.setSku(sku); //获取其他属性
    }
        model.addAttribute("buyCart",buyCart);
        return "/product/cart";
    }
    
    @RequestMapping(value="/shopping/clearCart.shtml")
    public String clearCart(HttpServletResponse response){
        Cookie cookie = new Cookie(Constants.BUYCART_COOKIE,null);
        cookie.setMaxAge(0);
        cookie.setPath("/");
        response.addCookie(cookie);
        return "redirect:/shopping/buyCart.shtml";
    }
  /**
   * 删除一个商品
   */
    @RequestMapping(value="/shopping/deleteItem.shtml")
    public String deleteItem(HttpServletRequest request,HttpServletResponse response,Integer skuId){
         ObjectMapper om = new ObjectMapper();
           om.setSerializationInclusion(Inclusion.NON_NULL);//去掉空值
           BuyCart buyCart = null;
           //获取cookie中的购物车
           Cookie []cookies = request.getCookies();
           if(cookies!=null&&cookies.length>0){
               for (Cookie cookie : cookies) {
                    if(Constants.BUYCART_COOKIE.equals(cookie.getName())){
                         String value = cookie.getValue();
                         //把json转化成对象
                         try {
                           buyCart = om.readValue(value,BuyCart.class);
                        } catch (Exception e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        } 
                         break;
                    }
                }
           }
        if(null!=buyCart){
              Sku sku = new Sku();
              sku.setId(skuId);
              BuyItem buyItem = new BuyItem();
              buyItem.setSku(sku);
              buyCart.deleteItem(buyItem);
              StringWriter stringWriter = new StringWriter();
              try {
                 om.writeValue(stringWriter, buyCart); //将对象转化为json
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
              Cookie cookie = new Cookie(Constants.BUYCART_COOKIE, stringWriter.toString());//购物车加入到cookie中
              //所有只能存一个购物车
              cookie.setPath("/");
              cookie.setMaxAge(60*60*24);
              response.addCookie(cookie);
        }
        
        return "redirect:/shopping/buyCart.shtml";
        
    }
    
    @RequestMapping(value="/buyer/trueBuy.shtml")
    public String trueBuy(HttpServletRequest request,HttpServletResponse response,ModelMap model){
        //获取cookie中的购物车
        ObjectMapper om = new ObjectMapper();
           om.setSerializationInclusion(Inclusion.NON_NULL);//去掉空值
           BuyCart buyCart = null;
           //获取cookie中的购物车
           Cookie []cookies = request.getCookies();
           if(cookies!=null&&cookies.length>0){
               for (Cookie cookie : cookies) {
                    if(Constants.BUYCART_COOKIE.equals(cookie.getName())){
                         String value = cookie.getValue();
                         //把json转化成对象
                         try {
                           buyCart = om.readValue(value,BuyCart.class);
                        } catch (Exception e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        } 
                         break;
                    }
                }
           }
           //判断购物车是否为空
           if(buyCart != null){
               //判断库存
               List<BuyItem> items =  buyCart.getItems();
               if(items.size()>0&&items!=null){
                   Integer i = items.size();
                   //判断库存
                   for(BuyItem item:items){
                        Sku sku = skuService.getSkuByKey(item.getSku().getId());
                //判断
                        if (sku.getStockInventory()<item.getAmount()) {
                            //删除该商品
                            buyCart.deleteItem(item);
                        }
                     Integer l = items.size();
                     if(i>l){ //判断是否删除过商品  
                         //删除过  购物车写回cookie
                         
                          StringWriter stringWriter = new StringWriter();
                          try {
                             om.writeValue(stringWriter, buyCart); //将对象转化为json
                        } catch (Exception e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                          Cookie cookie = new Cookie(Constants.BUYCART_COOKIE, stringWriter.toString());//购物车加入到cookie中
                          //所有只能存一个购物车
                          cookie.setPath("/");
                          cookie.setMaxAge(60*60*24);
                          response.addCookie(cookie);
                         
                         return "redirect:/shopping/buyCart.shtml";
                     }else{
                         //条件都满足
                         //收货地址加载
                         Buyer buyer = (Buyer) sessionProvider.getAttribute(request,Constants.BUYER_SESSION);
                         AddrQuery addrQuery = new AddrQuery();
                         addrQuery.setBuyerId(buyer.getUsername());
                         addrQuery.setIsDef(1);
                         List<Addr>addrs= addrService.getAddrList(addrQuery);
                        /* if(addrs!=null){
                             model.addAttribute("addr",addrs.get(0));
                         }*/
                         model.addAttribute("addr",addrs.get(0));
                         //装载购物车
                         List<BuyItem> it = buyCart.getItems();
                         for (BuyItem buyItem : it) {
                            Sku sku1 = skuService.getSkuByKey(buyItem.getSku().getId());
                            buyItem.setSku(sku1);
                        }
                         model.addAttribute("buyCart",buyCart);
                         return "product/productOrder";
                     }
                        
                   }
                   
                   
                   
               }else{
                   return "redirect:/shopping/buyCart.shtml";
               }
               
           }else{
               return "redirect:/shopping/buyCart.shtml";
           }
        return null;
    }
    @Resource
    private SkuService skuService;
    @Autowired
    private  AddrService addrService;
    @Autowired
    private SessionProvider sessionProvider;
}

 4.购买将购物车清空并将购物车信息保存到Order中

public class FrontOrderController {
    @Autowired
    private SkuService skuService;
    @Autowired
    private SessionProvider sessionprovider;
    @Autowired
    private OrderService orderService;
     @RequestMapping(value="/buyer/confirmOrder.shtml")
     public String confirmOrder(Order order,HttpServletRequest request,HttpServletResponse response){
        ObjectMapper om = new ObjectMapper();
        om.setSerializationInclusion(Inclusion.NON_NULL);
        BuyCart buyCart = null;
        Cookie []cookies = request.getCookies();
        if(cookies.length>0 && cookies!=null){
            for (Cookie cookie : cookies) {
              if(Constants.BUYCART_COOKIE.equals(cookie.getName())){
                  String value = cookie.getValue();
                  try {
                    buyCart = om.readValue(value,BuyCart.class);
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                  break;
              }
            }
        }
        //装满购物车
        List<BuyItem> items = buyCart.getItems();
        for (BuyItem buyItem : items) {
            Sku sku = skuService.getSkuByKey(buyItem.getSku().getId());
            buyItem.setSku(sku);
        }
        Buyer buyer = (Buyer) sessionprovider.getAttribute(request, Constants.BUYER_SESSION);
        order.setBuyerId(buyer.getUsername());
        orderService.addOrder(order, buyCart);
        //清除购物车
        Cookie cookie = new Cookie(Constants.BUYCART_COOKIE,null);
        cookie.setMaxAge(0);
        cookie.setPath("/");
        response.addCookie(cookie);
        
         return "/product/confirmOrder"; 
     }
}