电商秒杀基础构建项目笔记2(优化效验准则和商品模型创建)

第16步

优化效验规则，

先增加依赖，hibernate-validator，封装了一些效验规则，创建一个validator包，在里面创建一个ValitationResult，编写效验信息返回的类，创建ValidatorImpl，添加@Component，注入Bean实例化，定义效验，判断结果是否有错，在UserModel定义用户数据的约束，在service层调用新增的validator效验方法，注掉之前的校验方法。

引入validator的效验规则依赖

<!--效验规则-->
<dependency>
  <groupId>org.hibernate.validator</groupId>
  <artifactId>hibernate-validator</artifactId>
  <version>6.0.14.Final</version>
</dependency>

编写ValidationResult，

public class ValidationResult {
    //检查结果是否有错
    private boolean hasError = false;

    //存放错误信息的map
    private Map<String,String> errorMsgMap=new HashMap<>();

    public boolean isHasError() {
        return hasError;
    }

    public void setHasError(boolean hasError) {
        this.hasError = hasError;
    }

    public Map<String, String> getErrorMsgMap() {
        return errorMsgMap;
    }

    public void setErrorMsgMap(Map<String, String> errorMsgMap) {
        this.errorMsgMap = errorMsgMap;
    }
    //实现通用的通过格式化字符串信息获取错误结果的msg方法
    public String getErrorMsg(){
        return StringUtils.join(errorMsgMap.values().toArray(),",");
    }

编写ValidatorImpl

@Component
public class ValidatorImpl implements InitializingBean {

    //效验结果是否有错
    private Validator validator;

    //实现效验方法并返回结果
    public ValidationResult validate(Object bean){
        ValidationResult result = new ValidationResult();
        Set<ConstraintViolation<Object>> constraintViolationSet = validator.validate(bean);
        if (constraintViolationSet.size() >0){
            //有错误
            result.setHasError(true);
            constraintViolationSet.forEach(constraintViolation->{
                String errMsg = constraintViolation.getMessage();
                String propertyName = constraintViolation.getPropertyPath().toString();
                result.getErrorMsgMap().put(propertyName,errMsg);
            });
        }
        return result;
    }

    @Override
    public void afterPropertiesSet() throws Exception {
        //将hibernate validator通过工厂化的方式实例化
        this.validator= Validation.buildDefaultValidatorFactory().getValidator();
}

第17步

商品模型创建

首先创建编写ItemModel，描述商品的信息，之后再创建数据库，如果pom文件里面之前的逆向生成文件设置为打开时，要注意关闭，在Mybatis逆向生成里面增加数据库配置，将自增的id插入到mapper.xml文件中。

编写ItemModel

public class ItemModel {
    private Integer id;

    //商品的名称
    private String title;

    //商品的价格
    private BigDecimal price;


    //商品的库存
    private Integer stock;

    //商品的描述
    private String description;
    //商品的价格
    private String sales;

  // 商品描述图片的url
    private String imgUrl;
}

第18步

编写商品service层，逻辑实现，编写controller层，业务实现返回给前端。

先编写商品模型的接口ItemService，接着实现类实现逻辑业务，在dao层增加效验约束条件，在实现类里面编写创建商品逻辑，之后在商品库存xml文明增加一个通过用户id查询的sql语句，顺便补上接口，接着编写把商品的数据返回给前端，下一步就可以编写controller层了，创建商品项目controller和ItemVO(返回给前端看的商品数据)

商品模型接口

public interface ItemService {
    //创建商品
    ItemModel createItem(ItemModel itemModel) throws BusinessException;
    //商品列表浏览
    List<ItemModel> listItem();

    //商品详细浏览
    ItemModel getItemById(Integer id);
}

实现类

@Service
public class ItemServiceImpl implements ItemService {

    @Autowired
    private ValidatorImpl validator;
    @Autowired
    private ItemDOMapper itemDOMapper;
    @Autowired
    private ItemStockDOMapper itemStockDOMapper;

    private ItemDO convertItemDOFromItemModel(ItemModel itemModel){
        if (itemModel == null){
            return null;
        }
        ItemDO itemDO = new ItemDO();
        BeanUtils.copyProperties(itemModel,itemDO);
        itemDO.setPrice(itemModel.getPrice().doubleValue());

        return itemDO;
    }

    private ItemStockDO convertItemStockDOFromItemModel(ItemModel itemModel){
        if(itemModel == null) {
            return null;
        }
        ItemStockDO itemStockDO = new ItemStockDO();
        itemStockDO.setItemId(itemModel.getId());
        itemStockDO.setStock(itemModel.getStock());
        return itemStockDO;
    }

    @Override
    @Transactional
    public ItemModel createItem(ItemModel itemModel) throws BusinessException {
        //效验入参
        ValidationResult  result = validator.validate(itemModel);
        if (result.isHasError()){
            throw new BusinessException(EmBusinessError.PARAMETER_VALIDATION_ERROR,result.getErrorMsg());
        }

        //转化itemmodel->dataobject
        ItemDO itemDO = this.convertItemDOFromItemModel(itemModel);
        //写入数据库
        itemDOMapper.insertSelective(itemDO);
        itemModel.setId(itemDO.getId());

        ItemStockDO itemStockDO = this.convertItemStockDOFromItemModel(itemModel);
        itemStockDOMapper.insertSelective(itemStockDO);

        return this.getItemById(itemModel.getId());
    }

    @Override
    public List<ItemModel> listItem() {
        return null;
    }

    @Override
    public ItemModel getItemById(Integer id) {
        ItemDO itemDO = itemDOMapper.selectByPrimaryKey(id);
        if (itemDO == null){
            return null;
        }
        //获取操作库存数量
        ItemStockDO itemStockDO = itemStockDOMapper.selectByItemId(itemDO.getId());

        //将dataobject转化为model
        ItemModel itemModel = convertModelFromDataObject(itemDO, itemStockDO);
        return itemModel;
    }

    private ItemModel convertModelFromDataObject(ItemDO itemDO,ItemStockDO itemStockDO){
        ItemModel itemModel = new ItemModel();
        BeanUtils.copyProperties(itemDO,itemModel);
        itemModel.setPrice(new BigDecimal(itemDO.getPrice()));
        itemModel.setStock(itemStockDO.getStock());

        return itemModel;
    }

    @Override
    public boolean decreaseStock(Integer itemId, Integer amount) {
        return false;
    }

    @Override
    public void increaseSales(Integer itemId, Integer amount) throws BusinessException {

    }
}

在商品库存mapper.xml文件中增加一个查询sql

<select id="selectByItemId" parameterType="java.lang.Integer" resultMap="BaseResultMap">
  <!--
    WARNING - @mbg.generated
    This element is automatically generated by MyBatis Generator, do not modify.
    This element was generated on Thu Dec 03 20:49:59 CST 2020.
  -->
  select
  <include refid="Base_Column_List" />
  from item_stock
  where item_id = #{itemId,jdbcType=INTEGER}
</select>

编写ItemVO

public class ItemVO {
    private Integer id;
    //商品的名称
    private String title;
    //商品的价格
    private BigDecimal price;

    //商品的库存
    private Integer stock;

    //商品的描述
    private String description;
    //商品的价格
    private String sales;

    // 商品描述图片的url
    private String imgUrl;
}

编写ItemController

 @Controller("/item")
    @RequestMapping("/item")
    @CrossOrigin(origins = {"*"}, allowCredentials = "true")
    public class ItemController extends BaseController {

        @Autowired
        ItemService itemService;

        //创建商品
        @RequestMapping(value = "/create", method = {RequestMethod.POST}, consumes = {CONTENT_TYPE_FORMED})
        @ResponseBody
        public CommonReturnType createItem(@RequestParam(name = "title") String title,
                                           @RequestParam(name = "price") BigDecimal price,
                                           @RequestParam(name = "stock") Integer stock,
                                           @RequestParam(name = "imgUrl") String imgUrl,
                                           @RequestParam(name = "description") String description) throws BusinessException {
            // 封装service请求用来创建商品
            ItemModel itemModel = new ItemModel();
            itemModel.setTitle(title);
            itemModel.setPrice(price);
            itemModel.setStock(stock);
            itemModel.setImgUrl(imgUrl);
            itemModel.setDescription(description);

            ItemModel itemModelForReturn = itemService.createItem(itemModel);
            ItemVO itemVO = this.convertVOFromModel(itemModelForReturn);

            return CommonReturnType.create(itemVO);
        }

        private ItemVO convertVOFromModel(ItemModel itemModel) {
            if(itemModel == null) {
                return null;
            }
            ItemVO itemVO = new ItemVO();
            BeanUtils.copyProperties(itemModel,itemVO);

            return itemVO;
        }
}

第19步

编写商品模型的前端界面

在controller层实现商品详情浏览

编写createItem.html

<!DOCTYPE html>
<html>

    <head>
        <meta charset="utf-8">
        <link href="static/assets/global/plugins/bootstrap/css/bootstrap.min.css" rel="stylesheet" type="text/css"/>
        <link href="static/assets/global/css/components.css" rel="stylesheet" type="text/css"/>
        <link href="static/assets/admin/pages/css/login.css" rel="stylesheet" type="text/css"/>
        <script src="static/assets/global/plugins/jquery-1.11.0.min.js" type="text/javascript"></script>
    </head>

<body class="login">
   <div class="content">
      <h3 class="form-title">创建商品</h3>
      <div class="form-group">
         <label class="control-label">商品名</label>
         <div>
            <input class="form-control" type="text" name="title" id="title">
         </div>
      </div>
      <div class="form-group">
         <label class="control-label">商品价格</label>
         <div>
            <input class="form-control" type="text" name="price" id="price">
         </div>
      </div>
      <div class="form-group">
         <label class="control-label">商品库存</label>
         <div>
            <input class="form-control" type="text" name="stock" id="stock">
         </div>
      </div>
      <div class="form-group">
         <label class="control-label">商品描述</label>
         <div>
            <input class="form-control" type="text" name="description" id="description">
         </div>
      </div>
      <div class="form-group">
         <label class="control-label">商品图片</label>
         <div>
            <input class="form-control" type="text" name="imgUrl" id="imgUrl">
         </div>
      </div>
      <div class="form-actions">
         <button class="btn blue" id="create" type="submit">
            提交创建
         </button>
      </div>
   </div>
</body>

<script>
   $(document).ready(function() {
      $("#create").on("click", function() {
         var title = $("#title").val();
         var price = $("#price").val();
         var stock = $("#stock").val();
         var description = $("#description").val();
         var imgUrl = $("#imgUrl").val();
         if (title == null || title == "") {
            alert("商品名不能为空");
            return false;
         }
         if (price == null || price == "") {
            alert("商品价格不能为空");
            return false;
         }
         if (stock == null || stock == "") {
            alert("商品库存不能为空");
            return false;
         }
         if (description == null || description == "") {
            alert("商品描述不能为空");
            return false;
         }
         if (imgUrl == null || imgUrl == "") {
            alert("商品图片不能为空");
            return false;
         }
         $.ajax({
            type: "POST",
            contentType: "application/x-www-form-urlencoded",
            url: "http://localhost:8090/item/create",
            data: {
               "title": title,
               "price": price,
               "stock": stock,
               "description": description,
               "imgUrl": imgUrl
            },
            xhrFields:{
               withCredentials:true
            },
            success: function(data) {
               if (data.status == "success") {
                  alert("创建成功");
               } else {
                  alert("创建失败，原因为" + data.data.errMsg);
               }
            },
            error: function(data) {
               alert("创建失败，原因为" + data.responseText);
            }
         });
         return false;
      });
   });
</script>

</html>

在controller添加实现商品详情浏览
​

//商品详情页浏览
@RequestMapping(value = "/get", method = {RequestMethod.GET})
@ResponseBody
public CommonReturnType getItem(@RequestParam(name = "id")Integer id){
    ItemModel itemModel = itemService.getItemById(id);
    ItemVO itemVO = this.convertVOFromModel(itemModel);

    return CommonReturnType.create(itemVO);
}

private ItemVO convertVOFromModel(ItemModel itemModel) {
    if(itemModel == null) {
        return null;
    }
    ItemVO itemVO = new ItemVO();
    BeanUtils.copyProperties(itemModel,itemVO);

    return itemVO;
}

​