6步带你用Spring_Boot开发出商城高并发秒杀系统

摘要：本博客将介绍如何使用 Spring Boot 实现一个简单的商城秒杀系统,并通过使用 Redis 和 MySQL 来增强其性能和可靠性.

随着经济的发展和人们消费观念的转变,电子商务逐渐成为人们购物的主要方式之一.高并发是电子商务网站面临的一个重要挑战.本博客将介绍如何使用 Spring Boot 实现一个简单的商城秒杀系统,并通过使用 Redis 和 MySQL 来增强其性能和可靠性.

准备工作

在开始之前,您需要准备以下工具和环境：

Redis

MySQL

MyBatis

实现步骤

步骤一：创建数据库

首先,我们需要创建一个数据库来存储商品信息、订单信息和秒杀活动信息.今天这一节,我们使用 MySQL 数据库,创建一个名为 shop 的数据库,并建立三个表 goods、order 和 seckill.

表 goods 存储了所有的商品信息,包括商品编号、名称、描述、价格和库存数量等等.

CREATE TABLE +goods+ (
 +id+ int(11) NOT NULL AUTO_INCREMENT COMMENT '商品ID',
 +name+ varchar(50) NOT NULL COMMENT '商品名称',
 +description+ varchar(100) NOT NULL COMMENT '商品描述',
 +price+ decimal(10,2) NOT NULL COMMENT '商品价格',
 +stock_count+ int(11) NOT NULL COMMENT '商品库存',
 PRIMARY KEY (+id+)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='商品表';

表 order 存储了所有的订单信息,包括订单编号、用户ID、商品ID、秒杀活动ID 和订单状态等等.

CREATE TABLE +order+ (
 +id+ BIGINT(20) NOT NULL AUTO_INCREMENT COMMENT '订单ID',
 +user_id+ BIGINT(20) NOT NULL COMMENT '用户ID',
 +goods_id+ BIGINT(20) NOT NULL COMMENT '商品ID',
 +seckill_id+ BIGINT(20) DEFAULT NULL COMMENT '秒杀活动ID',
 +status+ TINYINT(4) NOT NULL COMMENT '订单状态,0-未支付,1-已支付,2-已发货,3-已收货,4-已退款,5-已完成',
 +create_time+ TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
 +update_time+ TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
 PRIMARY KEY (+id+),
 UNIQUE KEY +unique_order+ (+user_id+,+goods_id+)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='订单表';

表 seckill 存储了所有的秒杀活动信息,包括秒杀活动编号、商品ID、开始时间和结束时间等等.

CREATE TABLE +seckill+ (
 +id+ BIGINT(20) NOT NULL AUTO_INCREMENT COMMENT '秒杀活动ID',
 +goods_id+ BIGINT(20) NOT NULL COMMENT '商品ID',
 +start_time+ TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '开始时间',
 +end_time+ TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP COMMENT '结束时间',
 PRIMARY KEY (+id+)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COMMENT='秒杀活动表';

步骤二：创建 Spring Boot 项目

此时此刻呢,我们需要创建一个 Spring Boot 项目,用于实现商城高并发秒杀案例.可以使用 Spring Initializr 来快速创建一个基本的 Spring Boot 项目.

步骤三：配置 Redis 和 MySQL

在 Spring Boot 项目中,我们需要配置 Redis 和 MySQL 的连接信息.可以在 application.properties 文件中设置以下属性：

spring.redis.host=12⑦0.0.1
spring.redis.port=6379
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/shop?serverTimezone=Asia/ShanghaiuseSSL=falseallowPublicKeyRetrieval=true
spring.datasource.username=root
spring.datasource.password=123456

步骤四：编写实体类和 DAO 接口

在这一步中,我们需要定义三个实体类分别对应数据库中的 goods、order 和 seckill 表.同时,我们需要编写相应的 DAO 接口,用于操作这些实体类.

// 商品实体类
@Data
public class Goods {
 private Long id;
 private String name;
 private String description;
 private BigDecimal price;
 private Integer stockCount;
}
// 商品 DAO 接口
@Mapper
public interface GoodsDao {
@Select("SELECT * FROM goods WHERE id = #{id}")
@Update("UPDATE goods SET stock_count = stock_count - 1 WHERE id = #{id} AND stock_count > 0")
int reduceStockCount(Long id);
}
// 订单实体类
@Data
public class Order {
 private Long id;
 private Long userId;
 private Long goodsId;
 private Long seckillId;
 private Byte status;
 private Date createTime;
 private Date updateTime;
}
// 订单 DAO 接口
@Mapper
public interface OrderDao {
@Select("SELECT * FROM +order+ WHERE user_id = #{userId} AND goods_id = #{goodsId}")
Order getOrderByUserIdAndGoodsId(@Param("userId") Long userId, @Param("goodsId") Long goodsId);
@Insert("INSERT INTO +order+ (user_id, goods_id, seckill_id, status, create_time, update_time) VALUES (#{userId}, #{goodsId}, #{seckillId}, #{status},#{createTime},#{updateTime})")
int insertOrder(Order order);
@Select("SELECT o.*, g.name, g.price FROM +order+ o LEFT JOIN goods g ON o.goods_id = g.id WHERE o.user_id = #{userId}")
List getOrderListByUserId(Long userId);
}
// 秒杀活动实体类
@Data
public class Seckill {
 private Long id;
 private Long goodsId;
 private Date startTime;
 private Date endTime;
}
// 秒杀活动 DAO 接口
@Mapper
public interface SeckillDao {
@Select("SELECT * FROM seckill WHERE id = #{id}")
@Update("UPDATE seckill SET end_time = #{endTime} WHERE id = #{id}")
int updateSeckillEndTime(@Param("id") Long id, @Param("endTime") Date endTime);
}

步骤五：编写 Service 层和 Controller

在这一步中,我们需要编写 Service 层和 Controller 类,用于实现商城高并发秒杀案例的核心功能.

商品 Service 层：用于获取商品信息和减少商品库存数量.

@Service
public class GoodsService {
 private final GoodsDao goodsDao;
@Autowired
 public GoodsService(GoodsDao goodsDao) {
 this.goodsDao = goodsDao;
 }
 public Goods getGoodsById(Long id) {
 return goodsDao.getGoodsById(id);
 }
 public boolean reduceStockCount(Long id) {
 return goodsDao.reduceStockCount(id) > 0;
 }
}

@Service
public class OrderService {
 private final OrderDao orderDao;
@Autowired
 public OrderService(OrderDao orderDao) {
 this.orderDao = orderDao;
 }
 public Order createOrder(Long userId, Long goodsId, Long seckillId) {
    Order order = new Order();
    order.setStatus((byte) 0);
    order.setCreateTime(new Date());
    order.setUpdateTime(new Date());
    orderDao.insertOrder(order);
 return order;
 }
 public List getOrderListByUserId(Long userId) {
 return orderDao.getOrderListByUserId(userId);
 }
}

@Service
public class SeckillService {
 private final SeckillDao seckillDao;
@Autowired
 public SeckillService(SeckillDao seckillDao) {
 this.seckillDao = seckillDao;
 }
 public Seckill getSeckillById(Long id) {
 return seckillDao.getSeckillById(id);
 }
 public boolean updateSeckillEndTime(Long id, Date endTime) {
 return seckillDao.updateSeckillEndTime(id, endTime) > 0;
 }
}

@RestController
@RequestMapping("/order")
public class OrderController {
 private final OrderService orderService;
@Autowired
 public OrderController(OrderService orderService) {
 this.orderService = orderService;
 }
@PostMapping("/create")
 public CommonResult createOrder(@RequestParam("userId") Long userId,
                                       @RequestParam("goodsId") Long goodsId,
                                       @RequestParam("seckillId") Long seckillId) {
    Order order = orderService.createOrder(userId, goodsId, seckillId);
 if (order == null) {
 return CommonResult.failed(ResultCode.FAILURE);
 }
 return CommonResult.success(order);
 }
@GetMapping("/list")
 public CommonResult> getOrderListByUserId(@RequestParam("userId") Long userId) {
    List orderList = orderService.getOrderListByUserId(userId);
 return CommonResult.success(orderList);
 }
}

秒杀活动 Controller：用于处理秒杀活动相关的请求.

@RestController
@RequestMapping("/seckill")
public class SeckillController {
 private final SeckillService seckillService;
 private final GoodsService goodsService;
 private final OrderService orderService;
@Autowired
 public SeckillController(SeckillService seckillService, GoodsService goodsService, OrderService orderService) {
 this.seckillService = seckillService;
 this.goodsService = goodsService;
 this.orderService = orderService;
 }
@PostMapping("/start")
 public CommonResult