这是我参与8月更文挑战的第2天，活动详情查看：8月更文挑战

前言

文本已收录至我的GitHub仓库，欢迎Star：github.com/bin39232820…
种一棵树最好的时间是十年前，其次是现在
我知道很多人不玩qq了,但是怀旧一下,欢迎加入六脉神剑Java菜鸟学习群，群聊号码：549684836 鼓励大家在技术的路上写博客

絮叨

上一章已经完成大部分的基础学习，这个我们就来学习学习真正的基础案例吧，嘻嘻。

案例介绍

业务分析

模拟电商网站购物场景中的【下单】和【支付】

下单

用户请求订单系统下单
订单系统通过RPC调用订单服务下单
订单服务调用优惠券服务，扣减优惠券
订单服务调用调用库存服务，校验并扣减库存
订单服务调用用户服务，扣减用户余额
订单服务完成确认订单

支付

用户请求支付系统
支付系统调用第三方支付平台API进行发起支付流程
用户通过第三方支付平台支付成功后，第三方支付平台回调通知支付系统
支付系统调用订单服务修改订单状态
支付系统调用积分服务添加积分
支付系统调用日志服务记录日志

问题分析

用户提交订单后，扣减库存成功、扣减优惠券成功、使用余额成功，但是在确认订单操作失败，需要对库存、库存、余额进行回退。

问题1 如何保证数据的完整性?

使用MQ保证在下单失败后系统数据的完整性

问题2

用户通过第三方支付平台（支付宝、微信）支付成功后，第三方支付平台要通过回调API异步通知商家支付系统用户支付结果，支付系统根据支付结果修改订单状态、记录支付日志和给用户增加积分。

商家支付系统如何保证在收到第三方支付平台的异步通知时，如何快速给第三方支付凭条做出回应？

通过MQ进行数据分发，提高系统处理性能

技术分析

技术选型

SpringBoot
Dubbo
Zookeeper
RocketMQ
Mysql

SpringBoot整合RocketMQ

消息生产者

添加依赖

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.0.1.RELEASE</version>
</parent>

<properties>
    <rocketmq-spring-boot-starter-version>2.0.3</rocketmq-spring-boot-starter-version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.apache.rocketmq</groupId>
        <artifactId>rocketmq-spring-boot-starter</artifactId>
        <version>${rocketmq-spring-boot-starter-version}</version>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.6</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>

</dependencies>

配置文件

# application.properties
rocketmq.name-server=192.168.25.135:9876;192.168.25.138:9876
rocketmq.producer.group=my-group

启动类

@SpringBootApplication
public class MQProducerApplication {
    public static void main(String[] args) {
        SpringApplication.run(MQSpringBootApplication.class);
    }
}

测试类

@RunWith(SpringRunner.class)
@SpringBootTest(classes = {MQSpringBootApplication.class})
public class ProducerTest {

    @Autowired
    private RocketMQTemplate rocketMQTemplate;

    @Test
    public void test1(){
        rocketMQTemplate.convertAndSend("springboot-mq","hello springboot rocketmq");
    }
}

消息消费者

添加依赖

同消息生产者

配置文件

同消息生产者

启动类

@SpringBootApplication
public class MQConsumerApplication {
    public static void main(String[] args) {
        SpringApplication.run(MQSpringBootApplication.class);
    }

消息监听器

@Slf4j
@Component
@RocketMQMessageListener(topic = "springboot-mq",consumerGroup = "springboot-mq-consumer-1")
public class Consumer implements RocketMQListener<String> {

    @Override
    public void onMessage(String message) {
        log.info("Receive message："+message);
    }
}

SpringBoot整合Dubbo

下载dubbo-spring-boot-starter依赖包

将dubbo-spring-boot-starter安装到本地仓库

mvn install -Dmaven.skip.test=true

搭建Zookeeper集群

准备工作

安装JDK
将Zookeeper上传到服务器
解压Zookeeper，并创建data目录，将conf下的zoo_sample.cfg文件改名为zoo.cfg
建立/user/local/zookeeper-cluster,将解压后的Zookeeper复制到以下三个目录

/usr/local/zookeeper-cluster/zookeeper-1
/usr/local/zookeeper-cluster/zookeeper-2
/usr/local/zookeeper-cluster/zookeeper-3

修改/usr/local/zookeeper-cluster/zookeeper-1/conf/zoo.cfg

clientPort=2181
dataDir=/usr/local/zookeeper-cluster/zookeeper-1/data

修改/usr/local/zookeeper-cluster/zookeeper-2/conf/zoo.cfg

clientPort=2182
dataDir=/usr/local/zookeeper-cluster/zookeeper-2/data

修改/usr/local/zookeeper-cluster/zookeeper-3/conf/zoo.cfg

clientPort=2183
dataDir=/usr/local/zookeeper-cluster/zookeeper-3/data

配置集群

在每个 zookeeper 的 data 目录下创建一个 myid 文件，内容分别是 1、2、3 。这个文件就是记录每个服务器的 ID
在每一个 zookeeper 的 zoo.cfg 配置客户端访问端口（clientPort）和集群服务器 IP 列表。

集群服务器 IP 列表如下

server.1=192.168.25.140:2881:3881
server.2=192.168.25.140:2882:3882
server.3=192.168.25.140:2883:3883

解释：server.服务器 ID=服务器 IP 地址：服务器之间通信端口：服务器之间投票选举端口

启动集群

启动集群就是分别启动每个实例。

RPC服务接口

public interface IUserService {
    public String sayHello(String name);
}

服务提供者

添加依赖

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.0.1.RELEASE</version>
</parent>

<dependencies>
    <!--dubbo-->
    <dependency>
        <groupId>com.alibaba.spring.boot</groupId>
        <artifactId>dubbo-spring-boot-starter</artifactId>
        <version>2.0.0</version>
    </dependency>
	<!--spring-boot-stater-->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
        <exclusions>
            <exclusion>
                <artifactId>log4j-to-slf4j</artifactId>
                <groupId>org.apache.logging.log4j</groupId>
            </exclusion>
        </exclusions>
    </dependency>
	<!--zookeeper-->
    <dependency>
        <groupId>org.apache.zookeeper</groupId>
        <artifactId>zookeeper</artifactId>
        <version>3.4.10</version>
        <exclusions>
            <exclusion>
                <groupId>org.slf4j</groupId>
                <artifactId>slf4j-log4j12</artifactId>
            </exclusion>
            <exclusion>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
            </exclusion>
        </exclusions>
    </dependency>

    <dependency>
        <groupId>com.101tec</groupId>
        <artifactId>zkclient</artifactId>
        <version>0.9</version>
        <exclusions>
            <exclusion>
                <artifactId>slf4j-log4j12</artifactId>
                <groupId>org.slf4j</groupId>
            </exclusion>
        </exclusions>
    </dependency>
	<!--API-->
    <dependency>
        <groupId>com.itheima.demo</groupId>
        <artifactId>dubbo-api</artifactId>
        <version>1.0-SNAPSHOT</version>
    </dependency>

</dependencies>

配置文件

# application.properties
spring.application.name=dubbo-demo-provider
spring.dubbo.application.id=dubbo-demo-provider
spring.dubbo.application.name=dubbo-demo-provider
spring.dubbo.registry.address=zookeeper://192.168.25.140:2181;zookeeper://192.168.25.140:2182;zookeeper://192.168.25.140:2183
spring.dubbo.server=true
spring.dubbo.protocol.name=dubbo
spring.dubbo.protocol.port=20880

启动类

@EnableDubboConfiguration
@SpringBootApplication
public class ProviderBootstrap {

    public static void main(String[] args) throws IOException {
        SpringApplication.run(ProviderBootstrap.class,args);
    }

}

服务实现

@Component
@Service(interfaceClass = IUserService.class)
public class UserServiceImpl implements IUserService{
    @Override
    public String sayHello(String name) {
        return "hello:"+name;
    }
}

服务消费者

添加依赖

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.1.RELEASE</version>
    </parent>

<dependencies>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
    </dependency>

    <!--dubbo-->
    <dependency>
        <groupId>com.alibaba.spring.boot</groupId>
        <artifactId>dubbo-spring-boot-starter</artifactId>
        <version>2.0.0</version>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
        <exclusions>
            <exclusion>
                <artifactId>log4j-to-slf4j</artifactId>
                <groupId>org.apache.logging.log4j</groupId>
            </exclusion>
        </exclusions>
    </dependency>

    <!--zookeeper-->
    <dependency>
        <groupId>org.apache.zookeeper</groupId>
        <artifactId>zookeeper</artifactId>
        <version>3.4.10</version>
        <exclusions>
            <exclusion>
                <groupId>org.slf4j</groupId>
                <artifactId>slf4j-log4j12</artifactId>
            </exclusion>
            <exclusion>
                <groupId>log4j</groupId>
                <artifactId>log4j</artifactId>
            </exclusion>
        </exclusions>
    </dependency>

    <dependency>
        <groupId>com.101tec</groupId>
        <artifactId>zkclient</artifactId>
        <version>0.9</version>
        <exclusions>
            <exclusion>
                <artifactId>slf4j-log4j12</artifactId>
                <groupId>org.slf4j</groupId>
            </exclusion>
        </exclusions>
    </dependency>

    <!--API-->
    <dependency>
        <groupId>com.itheima.demo</groupId>
        <artifactId>dubbo-api</artifactId>
        <version>1.0-SNAPSHOT</version>
    </dependency>

</dependencies>

配置文件

# application.properties
spring.application.name=dubbo-demo-consumer
spring.dubbo.application.name=dubbo-demo-consumer
spring.dubbo.application.id=dubbo-demo-consumer
    spring.dubbo.registry.address=zookeeper://192.168.25.140:2181;zookeeper://192.168.25.140:2182;zookeeper://192.168.25.140:2183

启动类

@EnableDubboConfiguration
@SpringBootApplication
public class ConsumerBootstrap {
    public static void main(String[] args) {
        SpringApplication.run(ConsumerBootstrap.class);
    }
}

Controller

@RestController
@RequestMapping("/user")
public class UserController {

    @Reference
    private IUserService userService;

    @RequestMapping("/sayHello")
    public String sayHello(String name){
        return userService.sayHello(name);
    }

}

环境搭建

数据库

惠券表

商品表

订单表

订单商品日志表

用户表

用户余额日志表

订单支付表

MQ消息生产表

MQ消息消费表

项目初始化

shop系统基于Maven进行项目管理

3.1.1 工程浏览

父工程：shop-parent
订单系统：shop-order-web
支付系统：shop-pay-web
优惠券服务：shop-coupon-service
订单服务：shop-order-service
支付服务：shop-pay-service
商品服务：shop-goods-service
用户服务：shop-user-service
实体类：shop-pojo
持久层：shop-dao
接口层：shop-api
工具工程：shop-common

共12个系统

工程关系

Mybatis逆向工程使用

代码生成

使用Mybatis逆向工程针对数据表生成CURD持久层代码

代码导入

将实体类导入到shop-pojo工程
在服务层工程中导入对应的Mapper类和对应配置文件

公共类介绍

ID生成器

IDWorker：Twitter雪花算法
异常处理类

CustomerException：自定义异常类

CastException：异常抛出类
常量类

ShopCode：系统状态类
响应实体类

Result：封装响应状态和响应信息

下单业务

下单基本流程

接口定义

IOrderService

public interface IOrderService {
    /**
     * 确认订单
     * @param order
     * @return Result
     */
    Result confirmOrder(TradeOrder order);
}

业务类实现

@Slf4j
@Component
@Service(interfaceClass = IOrderService.class)
public class OrderServiceImpl implements IOrderService {

    @Override
    public Result confirmOrder(TradeOrder order) {
        //1.校验订单
       
        //2.生成预订单
       
        try {
            //3.扣减库存
            
            //4.扣减优惠券
           
            //5.使用余额
           
            //6.确认订单
            
            //7.返回成功状态
           
        } catch (Exception e) {
            //1.确认订单失败,发送消息
            
            //2.返回失败状态
        }

    }
}

校验订单

private void checkOrder(TradeOrder order) {
        //1.校验订单是否存在
        if(order==null){
            CastException.cast(ShopCode.SHOP_ORDER_INVALID);
        }
        //2.校验订单中的商品是否存在
        TradeGoods goods = goodsService.findOne(order.getGoodsId());
        if(goods==null){
            CastException.cast(ShopCode.SHOP_GOODS_NO_EXIST);
        }
        //3.校验下单用户是否存在
        TradeUser user = userService.findOne(order.getUserId());
        if(user==null){
            CastException.cast(ShopCode.SHOP_USER_NO_EXIST);
        }
        //4.校验商品单价是否合法
        if(order.getGoodsPrice().compareTo(goods.getGoodsPrice())!=0){
            CastException.cast(ShopCode.SHOP_GOODS_PRICE_INVALID);
        }
        //5.校验订单商品数量是否合法
        if(order.getGoodsNumber()>=goods.getGoodsNumber()){
            CastException.cast(ShopCode.SHOP_GOODS_NUM_NOT_ENOUGH);
        }

        log.info("校验订单通过");
}

生成预订单

private Long savePreOrder(TradeOrder order) {
        //1.设置订单状态为不可见
        order.setOrderStatus(ShopCode.SHOP_ORDER_NO_CONFIRM.getCode());
        //2.订单ID
        order.setOrderId(idWorker.nextId());
        //核算运费是否正确
        BigDecimal shippingFee = calculateShippingFee(order.getOrderAmount());
        if (order.getShippingFee().compareTo(shippingFee) != 0) {
            CastException.cast(ShopCode.SHOP_ORDER_SHIPPINGFEE_INVALID);
        }
        //3.计算订单总价格是否正确
        BigDecimal orderAmount = order.getGoodsPrice().multiply(new BigDecimal(order.getGoodsNumber()));
        orderAmount.add(shippingFee);
        if (orderAmount.compareTo(order.getOrderAmount()) != 0) {
            CastException.cast(ShopCode.SHOP_ORDERAMOUNT_INVALID);
        }

        //4.判断优惠券信息是否合法
        Long couponId = order.getCouponId();
        if (couponId != null) {
            TradeCoupon coupon = couponService.findOne(couponId);
            //优惠券不存在
            if (coupon == null) {
                CastException.cast(ShopCode.SHOP_COUPON_NO_EXIST);
            }
            //优惠券已经使用
            if ((ShopCode.SHOP_COUPON_ISUSED.getCode().toString())
                .equals(coupon.getIsUsed().toString())) {
                CastException.cast(ShopCode.SHOP_COUPON_INVALIED);
            }
            order.setCouponPaid(coupon.getCouponPrice());
        } else {
            order.setCouponPaid(BigDecimal.ZERO);
        }

        //5.判断余额是否正确
        BigDecimal moneyPaid = order.getMoneyPaid();
        if (moneyPaid != null) {
            //比较余额是否大于0
            int r = order.getMoneyPaid().compareTo(BigDecimal.ZERO);
            //余额小于0
            if (r == -1) {
                CastException.cast(ShopCode.SHOP_MONEY_PAID_LESS_ZERO);
            }
            //余额大于0
            if (r == 1) {
                //查询用户信息
                TradeUser user = userService.findOne(order.getUserId());
                if (user == null) {
                    CastException.cast(ShopCode.SHOP_USER_NO_EXIST);
                }
            //比较余额是否大于用户账户余额
            if (user.getUserMoney().compareTo(order.getMoneyPaid().longValue()) == -1) {
                CastException.cast(ShopCode.SHOP_MONEY_PAID_INVALID);
            }
            order.setMoneyPaid(order.getMoneyPaid());
        }
    } else {
        order.setMoneyPaid(BigDecimal.ZERO);
    }
    //计算订单支付总价
    order.setPayAmount(orderAmount.subtract(order.getCouponPaid())
                       .subtract(order.getMoneyPaid()));
    //设置订单添加时间
    order.setAddTime(new Date());

    //保存预订单
    int r = orderMapper.insert(order);
    if (ShopCode.SHOP_SUCCESS.getCode() != r) {
        CastException.cast(ShopCode.SHOP_ORDER_SAVE_ERROR);
    }
    log.info("订单:["+order.getOrderId()+"]预订单生成成功");
    return order.getOrderId();
}

扣减库存

通过dubbo调用商品服务完成扣减库存

private void reduceGoodsNum(TradeOrder order) {
        TradeGoodsNumberLog goodsNumberLog = new TradeGoodsNumberLog();
        goodsNumberLog.setGoodsId(order.getGoodsId());
        goodsNumberLog.setOrderId(order.getOrderId());
        goodsNumberLog.setGoodsNumber(order.getGoodsNumber());
        Result result = goodsService.reduceGoodsNum(goodsNumberLog);
        if (result.getSuccess().equals(ShopCode.SHOP_FAIL.getSuccess())) {
            CastException.cast(ShopCode.SHOP_REDUCE_GOODS_NUM_FAIL);
        }
        log.info("订单:["+order.getOrderId()+"]扣减库存["+order.getGoodsNumber()+"个]成功");
    }

商品服务GoodsService扣减库存

@Override
public Result reduceGoodsNum(TradeGoodsNumberLog goodsNumberLog) {
    if (goodsNumberLog == null ||
            goodsNumberLog.getGoodsNumber() == null ||
            goodsNumberLog.getOrderId() == null ||
            goodsNumberLog.getGoodsNumber() == null ||
            goodsNumberLog.getGoodsNumber().intValue() <= 0) {
        CastException.cast(ShopCode.SHOP_REQUEST_PARAMETER_VALID);
    }
    TradeGoods goods = goodsMapper.selectByPrimaryKey(goodsNumberLog.getGoodsId());
    if(goods.getGoodsNumber()<goodsNumberLog.getGoodsNumber()){
        //库存不足
        CastException.cast(ShopCode.SHOP_GOODS_NUM_NOT_ENOUGH);
    }
    //减库存
    goods.setGoodsNumber(goods.getGoodsNumber()-goodsNumberLog.getGoodsNumber());
    goodsMapper.updateByPrimaryKey(goods);


    //记录库存操作日志
    goodsNumberLog.setGoodsNumber(-(goodsNumberLog.getGoodsNumber()));
    goodsNumberLog.setLogTime(new Date());
    goodsNumberLogMapper.insert(goodsNumberLog);

    return new Result(ShopCode.SHOP_SUCCESS.getSuccess(),ShopCode.SHOP_SUCCESS.getMessage());
}

扣减优惠券

private void changeCoponStatus(TradeOrder order) {
    //判断用户是否使用优惠券
    if (!StringUtils.isEmpty(order.getCouponId())) {
        //封装优惠券对象
        TradeCoupon coupon = couponService.findOne(order.getCouponId());
        coupon.setIsUsed(ShopCode.SHOP_COUPON_ISUSED.getCode());
        coupon.setUsedTime(new Date());
        coupon.setOrderId(order.getOrderId());
        Result result = couponService.changeCouponStatus(coupon);
        //判断执行结果
        if (result.getSuccess().equals(ShopCode.SHOP_FAIL.getSuccess())) {
            //优惠券使用失败
            CastException.cast(ShopCode.SHOP_COUPON_USE_FAIL);
        }
        log.info("订单:["+order.getOrderId()+"]使用扣减优惠券["+coupon.getCouponPrice()+"元]成功");
    }

}

优惠券服务CouponService更改优惠券状态

@Override
public Result changeCouponStatus(TradeCoupon coupon) {
    try {
        //判断请求参数是否合法
        if (coupon == null || StringUtils.isEmpty(coupon.getCouponId())) {
            CastException.cast(ShopCode.SHOP_REQUEST_PARAMETER_VALID);
        }
		//更新优惠券状态为已使用
        couponMapper.updateByPrimaryKey(coupon);
        return new Result(ShopCode.SHOP_SUCCESS.getSuccess(), ShopCode.SHOP_SUCCESS.getMessage());
    } catch (Exception e) {
        return new Result(ShopCode.SHOP_FAIL.getSuccess(), ShopCode.SHOP_FAIL.getMessage());
    }
}

扣减用户余额

通过用户服务完成扣减余额通过用户服务完成扣减余额

private void reduceMoneyPaid(TradeOrder order) {
    //判断订单中使用的余额是否合法
    if (order.getMoneyPaid() != null && order.getMoneyPaid().compareTo(BigDecimal.ZERO) == 1) {
        TradeUserMoneyLog userMoneyLog = new TradeUserMoneyLog();
        userMoneyLog.setOrderId(order.getOrderId());
        userMoneyLog.setUserId(order.getUserId());
        userMoneyLog.setUseMoney(order.getMoneyPaid());
        userMoneyLog.setMoneyLogType(ShopCode.SHOP_USER_MONEY_PAID.getCode());
        //扣减余额
        Result result = userService.changeUserMoney(userMoneyLog);
        if (result.getSuccess().equals(ShopCode.SHOP_FAIL.getSuccess())) {
            CastException.cast(ShopCode.SHOP_USER_MONEY_REDUCE_FAIL);
        }
        log.info("订单:["+order.getOrderId()+"扣减余额["+order.getMoneyPaid()+"元]成功]");
    }
}

用户服务UserService,

@Override
public Result changeUserMoney(TradeUserMoneyLog userMoneyLog) {
    //判断请求参数是否合法
    if (userMoneyLog == null
            || userMoneyLog.getUserId() == null
            || userMoneyLog.getUseMoney() == null
            || userMoneyLog.getOrderId() == null
            || userMoneyLog.getUseMoney().compareTo(BigDecimal.ZERO) <= 0) {
        CastException.cast(ShopCode.SHOP_REQUEST_PARAMETER_VALID);
    }

    //查询该订单是否存在付款记录
    TradeUserMoneyLogExample userMoneyLogExample = new TradeUserMoneyLogExample();
    userMoneyLogExample.createCriteria()
            .andUserIdEqualTo(userMoneyLog.getUserId())
            .andOrderIdEqualTo(userMoneyLog.getOrderId());
   int count = userMoneyLogMapper.countByExample(userMoneyLogExample);
   TradeUser tradeUser = new TradeUser();
   tradeUser.setUserId(userMoneyLog.getUserId());
   tradeUser.setUserMoney(userMoneyLog.getUseMoney().longValue());
   //判断余额操作行为
   //【付款操作】
   if (userMoneyLog.getMoneyLogType().equals(ShopCode.SHOP_USER_MONEY_PAID.getCode())) {
           //订单已经付款，则抛异常
           if (count > 0) {
                CastException.cast(ShopCode.SHOP_ORDER_PAY_STATUS_IS_PAY);
            }
       	   //用户账户扣减余额
           userMapper.reduceUserMoney(tradeUser);
       }
    //【退款操作】
    if (userMoneyLog.getMoneyLogType().equals(ShopCode.SHOP_USER_MONEY_REFUND.getCode())) {
         //如果订单未付款,则不能退款,抛异常
         if (count == 0) {
         CastException.cast(ShopCode.SHOP_ORDER_PAY_STATUS_NO_PAY);
     }
     //防止多次退款
     userMoneyLogExample = new TradeUserMoneyLogExample();
     userMoneyLogExample.createCriteria()
             .andUserIdEqualTo(userMoneyLog.getUserId())
                .andOrderIdEqualTo(userMoneyLog.getOrderId())
                .andMoneyLogTypeEqualTo(ShopCode.SHOP_USER_MONEY_REFUND.getCode());
     count = userMoneyLogMapper.countByExample(userMoneyLogExample);
     if (count > 0) {
         CastException.cast(ShopCode.SHOP_USER_MONEY_REFUND_ALREADY);
     }
     	//用户账户添加余额
        userMapper.addUserMoney(tradeUser);
    }


    //记录用户使用余额日志
    userMoneyLog.setCreateTime(new Date());
    userMoneyLogMapper.insert(userMoneyLog);
    return new Result(ShopCode.SHOP_SUCCESS.getSuccess(),ShopCode.SHOP_SUCCESS.getMessage());
}

确认订单

private void updateOrderStatus(TradeOrder order) {
    order.setOrderStatus(ShopCode.SHOP_ORDER_CONFIRM.getCode());
    order.setPayStatus(ShopCode.SHOP_ORDER_PAY_STATUS_NO_PAY.getCode());
    order.setConfirmTime(new Date());
    int r = orderMapper.updateByPrimaryKey(order);
    if (r <= 0) {
        CastException.cast(ShopCode.SHOP_ORDER_CONFIRM_FAIL);
    }
    log.info("订单:["+order.getOrderId()+"]状态修改成功");
}

失败补偿机制

消息发送方

配置RocketMQ属性值

ocketmq.name-server=192.168.25.135:9876;192.168.25.138:9876
rocketmq.producer.group=orderProducerGroup

mq.order.consumer.group.name=order_orderTopic_cancel_group
mq.order.topic=orderTopic
mq.order.tag.confirm=order_confirm
mq.order.tag.cancel=order_cancel

注入模板类和属性值信息

 @Autowired
 private RocketMQTemplate rocketMQTemplate;

 @Value("${mq.order.topic}")
 private String topic;

 @Value("${mq.order.tag.cancel}")
 private String cancelTag;

发送下单失败消息

@Override
public Result confirmOrder(TradeOrder order) {
    //1.校验订单
    //2.生成预订
    try {
        //3.扣减库存
        //4.扣减优惠券
        //5.使用余额
        //6.确认订单
    } catch (Exception e) {
        //确认订单失败,发送消息
        CancelOrderMQ cancelOrderMQ = new CancelOrderMQ();
        cancelOrderMQ.setOrderId(order.getOrderId());
        cancelOrderMQ.setCouponId(order.getCouponId());
        cancelOrderMQ.setGoodsId(order.getGoodsId());
        cancelOrderMQ.setGoodsNumber(order.getGoodsNumber());
        cancelOrderMQ.setUserId(order.getUserId());
        cancelOrderMQ.setUserMoney(order.getMoneyPaid());
        try {
            sendMessage(topic, 
                        cancelTag, 
                        cancelOrderMQ.getOrderId().toString(), 
                    JSON.toJSONString(cancelOrderMQ));
    } catch (Exception e1) {
        e1.printStackTrace();
            CastException.cast(ShopCode.SHOP_MQ_SEND_MESSAGE_FAIL);
        }
        return new Result(ShopCode.SHOP_FAIL.getSuccess(), ShopCode.SHOP_FAIL.getMessage());
    }
}

private void sendMessage(String topic, String tags, String keys, String body) throws Exception {
    //判断Topic是否为空
    if (StringUtils.isEmpty(topic)) {
        CastException.cast(ShopCode.SHOP_MQ_TOPIC_IS_EMPTY);
    }
    //判断消息内容是否为空
    if (StringUtils.isEmpty(body)) {
        CastException.cast(ShopCode.SHOP_MQ_MESSAGE_BODY_IS_EMPTY);
    }
    //消息体
    Message message = new Message(topic, tags, keys, body.getBytes());
    //发送消息
    rocketMQTemplate.getProducer().send(message);
}

消费接收方

配置RocketMQ属性值

rocketmq.name-server=192.168.25.135:9876;192.168.25.138:9876
mq.order.consumer.group.name=order_orderTopic_cancel_group
mq.order.topic=orderTopic

创建监听类，消费消息

@Slf4j
@Component
@RocketMQMessageListener(topic = "${mq.order.topic}", 
                         consumerGroup = "${mq.order.consumer.group.name}",
                         messageModel = MessageModel.BROADCASTING)
public class CancelOrderConsumer implements RocketMQListener<MessageExt>{

    @Override
    public void onMessage(MessageExt messageExt) {
        ...
    }
}

回退库存

消息消费者

@Slf4j
@Component
@RocketMQMessageListener(topic = "${mq.order.topic}",consumerGroup = "${mq.order.consumer.group.name}",messageModel = MessageModel.BROADCASTING )
public class CancelMQListener implements RocketMQListener<MessageExt>{


    @Value("${mq.order.consumer.group.name}")
    private String groupName;

    @Autowired
    private TradeGoodsMapper goodsMapper;

    @Autowired
    private TradeMqConsumerLogMapper mqConsumerLogMapper;

    @Autowired
    private TradeGoodsNumberLogMapper goodsNumberLogMapper;

    @Override
    public void onMessage(MessageExt messageExt) {
        String msgId=null;
        String tags=null;
        String keys=null;
        String body=null;
        try {
            //1. 解析消息内容
            msgId = messageExt.getMsgId();
            tags= messageExt.getTags();
            keys= messageExt.getKeys();
            body= new String(messageExt.getBody(),"UTF-8");

            log.info("接受消息成功");

            //2. 查询消息消费记录
            TradeMqConsumerLogKey primaryKey = new TradeMqConsumerLogKey();
            primaryKey.setMsgTag(tags);
            primaryKey.setMsgKey(keys);
            primaryKey.setGroupName(groupName);
            TradeMqConsumerLog mqConsumerLog = mqConsumerLogMapper.selectByPrimaryKey(primaryKey);

            if(mqConsumerLog!=null){
                //3. 判断如果消费过...
                //3.1 获得消息处理状态
                Integer status = mqConsumerLog.getConsumerStatus();
                //处理过...返回
                if(ShopCode.SHOP_MQ_MESSAGE_STATUS_SUCCESS.getCode().intValue()==status.intValue()){
                    log.info("消息:"+msgId+",已经处理过");
                    return;
                }

                //正在处理...返回
                if(ShopCode.SHOP_MQ_MESSAGE_STATUS_PROCESSING.getCode().intValue()==status.intValue()){
                    log.info("消息:"+msgId+",正在处理");
                    return;
                }

                //处理失败
                if(ShopCode.SHOP_MQ_MESSAGE_STATUS_FAIL.getCode().intValue()==status.intValue()){
                    //获得消息处理次数
                    Integer times = mqConsumerLog.getConsumerTimes();
                    if(times>3){
                        log.info("消息:"+msgId+",消息处理超过3次,不能再进行处理了");
                        return;
                    }
                    mqConsumerLog.setConsumerStatus(ShopCode.SHOP_MQ_MESSAGE_STATUS_PROCESSING.getCode());

                    //使用数据库乐观锁更新
                    TradeMqConsumerLogExample example = new TradeMqConsumerLogExample();
                    TradeMqConsumerLogExample.Criteria criteria = example.createCriteria();
                    criteria.andMsgTagEqualTo(mqConsumerLog.getMsgTag());
                    criteria.andMsgKeyEqualTo(mqConsumerLog.getMsgKey());
                    criteria.andGroupNameEqualTo(groupName);
                    criteria.andConsumerTimesEqualTo(mqConsumerLog.getConsumerTimes());
                    int r = mqConsumerLogMapper.updateByExampleSelective(mqConsumerLog, example);
                    if(r<=0){
                        //未修改成功,其他线程并发修改
                        log.info("并发修改,稍后处理");
                    }
                }

            }else{
                //4. 判断如果没有消费过...
                mqConsumerLog = new TradeMqConsumerLog();
                mqConsumerLog.setMsgTag(tags);
                mqConsumerLog.setMsgKey(keys);
                mqConsumerLog.setConsumerStatus(ShopCode.SHOP_MQ_MESSAGE_STATUS_PROCESSING.getCode());
                mqConsumerLog.setMsgBody(body);
                mqConsumerLog.setMsgId(msgId);
                mqConsumerLog.setConsumerTimes(0);

                //将消息处理信息添加到数据库
                mqConsumerLogMapper.insert(mqConsumerLog);
            }
            //5. 回退库存
            MQEntity mqEntity = JSON.parseObject(body, MQEntity.class);
            Long goodsId = mqEntity.getGoodsId();
            TradeGoods goods = goodsMapper.selectByPrimaryKey(goodsId);
            goods.setGoodsNumber(goods.getGoodsNumber()+mqEntity.getGoodsNum());
            goodsMapper.updateByPrimaryKey(goods);

            //记录库存操作日志
            TradeGoodsNumberLog goodsNumberLog = new TradeGoodsNumberLog();
            goodsNumberLog.setOrderId(mqEntity.getOrderId());
            goodsNumberLog.setGoodsId(goodsId);
            goodsNumberLog.setGoodsNumber(mqEntity.getGoodsNum());
            goodsNumberLog.setLogTime(new Date());
            goodsNumberLogMapper.insert(goodsNumberLog);

            //6. 将消息的处理状态改为成功
            mqConsumerLog.setConsumerStatus(ShopCode.SHOP_MQ_MESSAGE_STATUS_SUCCESS.getCode());
            mqConsumerLog.setConsumerTimestamp(new Date());
            mqConsumerLogMapper.updateByPrimaryKey(mqConsumerLog);
            log.info("回退库存成功");
        } catch (Exception e) {
            e.printStackTrace();
            TradeMqConsumerLogKey primaryKey = new TradeMqConsumerLogKey();
            primaryKey.setMsgTag(tags);
            primaryKey.setMsgKey(keys);
            primaryKey.setGroupName(groupName);
            TradeMqConsumerLog mqConsumerLog = mqConsumerLogMapper.selectByPrimaryKey(primaryKey);
            if(mqConsumerLog==null){
                //数据库未有记录
                mqConsumerLog = new TradeMqConsumerLog();
                mqConsumerLog.setMsgTag(tags);
                mqConsumerLog.setMsgKey(keys);
                mqConsumerLog.setConsumerStatus(ShopCode.SHOP_MQ_MESSAGE_STATUS_FAIL.getCode());
                mqConsumerLog.setMsgBody(body);
                mqConsumerLog.setMsgId(msgId);
                mqConsumerLog.setConsumerTimes(1);
                mqConsumerLogMapper.insert(mqConsumerLog);
            }else{
                mqConsumerLog.setConsumerTimes(mqConsumerLog.getConsumerTimes()+1);
                mqConsumerLogMapper.updateByPrimaryKeySelective(mqConsumerLog);
            }
        }

    }
}

然后其他退回的东西这边就不写了，差不多流程

结尾

这种就是我们项目中真实的案例了。

日常求赞

好了各位，以上就是这篇文章的全部内容了，能看到这里的人呀，都是真粉。

创作不易，各位的支持和认可，就是我创作的最大动力，我们下篇文章见

六脉神剑 | 文【原创】如果本篇博客有任何错误，请批评指教，不胜感激！

小六六带大家来撸撸rocketmq(四)

前言

絮叨

案例介绍

业务分析

下单

支付

问题分析

技术分析

技术选型

SpringBoot整合RocketMQ

消息生产者

添加依赖

配置文件

启动类

测试类

消息消费者

添加依赖

配置文件

启动类

消息监听器

SpringBoot整合Dubbo

搭建Zookeeper集群

准备工作

配置集群

启动集群

RPC服务接口

服务提供者

环境搭建

数据库

项目初始化

代码生成

代码导入

公共类介绍

下单业务

下单基本流程

接口定义

业务类实现

校验订单

生成预订单

扣减库存

商品服务GoodsService扣减库存

扣减优惠券

优惠券服务CouponService更改优惠券状态

扣减用户余额

用户服务UserService,

确认订单

失败补偿机制

消息发送方

消费接收方

回退库存

消息消费者

结尾

日常求赞