RocketMQ-双十一抗压-下订单与库存的业务乐观锁机制业务实现

在bfxy-store-api模块里新增一个接口

package com.bfxy.store.service.api;

import java.util.Date;

public interface StoreServiceApi {

    int selectVersion(String supplierId, String goodsId);

    int updateStoreCountByVersion(int version, String supplierId, String goodIds, String updateBy, Date updateTime);

    int selectStoreCount(String supplierId, String goodsId);

}

在bfxy-order模块中新增的代码如下

package com.bfxy.order.web;

import com.bfxy.order.service.OrderService;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;
import com.netflix.hystrix.contrib.javanica.annotation.HystrixProperty;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class OrderController {

    @Autowired
    private OrderService orderService;

    @RequestMapping("/createOrder")
    public String createOrder(@RequestParam("cityId") String cityId,
                              @RequestParam("platformId") String platformId,
                              @RequestParam("userId") String userId,
                              @RequestParam("suppliedId") String suppliedId,
                              @RequestParam("goodsId") String goodsId) throws InterruptedException {
        return orderService.createOrder(cityId, platformId, userId, suppliedId, goodsId) ? "下单成功" : "下单失败";
    }

}

package com.bfxy.order.constants;

public enum OrderStatus {

    ORDER_CREATED("1"),
    ORDER_PAYED("2"),
    ORDER_FAIL("3");

    private String status;

    OrderStatus(String status) {
        this.status = status;
    }

    public String getValue() {
        return status;
    }

}

package com.bfxy.order.service;

public interface OrderService {
    boolean createOrder(String cityId, String platformId, String userId, String suppliedId, String goodsId);
}

package com.bfxy.order.service.impl;

import com.alibaba.dubbo.config.annotation.Reference;
import com.bfxy.order.constants.OrderStatus;
import com.bfxy.order.entity.Order;
import com.bfxy.order.mapper.OrderMapper;
import com.bfxy.order.service.OrderService;
import com.bfxy.store.service.api.StoreServiceApi;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.Date;
import java.util.UUID;

@Service
public class OrderServiceImpl implements OrderService {

    @Autowired
    private OrderMapper orderMapper;

    @Reference(
            version = "1.0.0",
            application = "${dubbo.application.id}",
            interfaceName = "com.bfxy.store.service.api.StoreServiceApi",
            check = false,
            timeout = 3000,
            retries = 0 //读请求允许重试3次,写请求不要进行重试
    )
    private StoreServiceApi storeServiceApi;

    @Override
    public boolean createOrder(String cityId, String platformId, String userId, String suppliedId, String goodsId) {
        boolean flag = true;
        try {
            Order order = new Order();
            order.setOrderId(UUID.randomUUID().toString());
            order.setOrderType("1");
            order.setCityId(cityId);
            order.setPlatformId(platformId);
            order.setUserId(userId);
            order.setSupplierId(suppliedId);
            order.setGoodsId(goodsId);
            order.setOrderStatus(OrderStatus.ORDER_CREATED.getValue());
            order.setRemark("");
            order.setCreateBy("admin");
            order.setCreateTime(new Date());
            order.setUpdateBy("admin");
            order.setUpdateTime(new Date());

            int currentVersion = storeServiceApi.selectVersion(suppliedId, goodsId);
            int updateRetCount = storeServiceApi.updateStoreCountByVersion(currentVersion, suppliedId, goodsId, "admin", new Date());

            if (updateRetCount == 1) {
                //TODO 如果出现SQL异常入库失败,那么要对库存的数量和版本号进行回滚操作
                orderMapper.insertSelective(order);
            }
            //没有更新成功:1.高并发时乐观锁生效,2.库存不足
            else if (updateRetCount == 0) {
                flag = false;//下单标识失败
                int currentStoreCount = storeServiceApi.selectStoreCount(suppliedId, goodsId);
                if (currentStoreCount == 0) {
                    System.err.println("-----当前库存不足...");
                } else {
                    System.err.println("-----乐观锁生效...");
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
            // 具体捕获的异常是什么异常
            flag = false;
        }

        return flag;
    }
}

在bfxy-store新增以下代码

package com.bfxy.store.service.provider;

import com.alibaba.dubbo.config.annotation.Service;
import com.bfxy.store.mapper.StoreMapper;
import com.bfxy.store.service.api.StoreServiceApi;
import org.springframework.beans.factory.annotation.Autowired;

import java.util.Date;

@Service(
        version = "1.0.0",
        application = "${dubbo.application.id}",
        protocol = "${dubbo.protocol.id}",
        registry = "${dubbo.registry.id}"
)
public class StoreServiceProvider implements StoreServiceApi {

    @Autowired
    private StoreMapper storeMapper;

    @Override
    public int selectVersion(String supplierId, String goodsId) {
        return storeMapper.selectVersion(supplierId, goodsId);
    }

    @Override
    public int updateStoreCountByVersion(int version, String supplierId, String goodIds, String updateBy, Date updateTime) {
        return storeMapper.updateStoreCountByVersion(version, supplierId, goodIds, updateBy, updateTime);
    }

    @Override
    public int selectStoreCount(String supplierId, String goodsId) {
        return storeMapper.selectStoreCount(supplierId, goodsId);
    }
}

在bfxy-store模块下的StoreMapper.xml新增以下三个查询

    <select id="selectVersion" resultType="int">
    select version from t_store ts
                   where ts.supplier_id = #{supplierId,jdbcType=VARCHAR}
                         and 
                         ts.goods_id = #{goodsId,jdbcType=VARCHAR}
  </select>

    <update id="updateStoreCountByVersion">
    update t_store ts
    set 
      store_count = store_count - 1,
      version = version + 1,
      update_by = #{updateBy,jdbcType=VARCHAR},
      update_time = #{updateTime,jdbcType=TIMESTAMP}
    where  ts.supplier_id = #{supplierId,jdbcType=VARCHAR}
           and
           ts.goods_id = #{goodsId,jdbcType=VARCHAR}
           and
           ts.version = #{version,jdbcType=INTEGER}
           and  
           ts.store_count > 0
  </update>

    <select id="selectStoreCount" resultType="int">
    select store_count from t_store ts
                       where ts.supplier_id = #{supplierId,jdbcType=VARCHAR}
                             and
                             ts.goods_id = #{goodsId,jdbcType=VARCHAR}
  </select>