1. Description of the environment
JeecgBoot 3.0
seata version: 1.3.0
2. Database construction
First create 3 databases, plus jeecg-boot's own database, a total of 4 databases
First introduce the undo_log table in the four databases
CREATE TABLE `undo_log` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`branch_id` bigint(20) NOT NULL,
`xid` varchar(100) NOT NULL,
`context` varchar(128) NOT NULL,
`rollback_info` longblob NOT NULL,
`log_status` int(11) NOT NULL,
`log_created` datetime NOT NULL,
`log_modified` datetime NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `ux_undo_log` (`xid`,`branch_id`)
) ENGINE=InnoDB AUTO_INCREMENT=137 DEFAULT CHARSET=utf8;In jeecg-account, create table and insert data
CREATE TABLE `account` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`user_id` int(11) DEFAULT NULL,
`balance` int(11) DEFAULT NULL,
`update_time` datetime DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8mb4;
INSERT INTO `account` (`id`, `user_id`, `balance`, `update_time`) VALUES ('1', '1', '200', '2021-01-15 00:02:17');In the jeecg-order library, create a table
CREATE TABLE `orders` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`user_id` int(11) DEFAULT NULL,
`product_id` int(11) DEFAULT NULL,
`pay_amount` int(11) DEFAULT NULL,
`add_time` datetime DEFAULT NULL,
`update_time` datetime DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=50 DEFAULT CHARSET=utf8mb4;In jeecg-product, create table and insert data
CREATE TABLE `product` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(255) DEFAULT NULL,
`price` int(11) DEFAULT NULL,
`stock` int(11) DEFAULT NULL,
`add_time` datetime DEFAULT NULL,
`update_time` datetime DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8mb4;
INSERT INTO `product` (`id`, `name`, `price`, `stock`, `add_time`, `update_time`) VALUES ('1', '电池', '10', '67', '2021-01-15 00:00:32', '2021-01-15 00:00:35');3. Coordinate introduction
<!-- seata-spring-boot-starter -->
<dependency>
<groupId>io.seata</groupId>
<artifactId>seata-spring-boot-starter</artifactId>
<version>1.3.0</version>
</dependency>4. yml configuration file
seata:
config:
type: file
application-id: springboot-seata
# enable-auto-data-source-proxy: false
registry:
type: file
service:
grouplist:
default: 127.0.0.1:8091
vgroup-mapping:
springboot-seata-group: default
# seata 事务组编号 用于TC集群名
tx-service-group: springboot-seata-group
spring:
datasource:
dynamic:
datasource:
master:
url: jdbc:mysql://127.0.0.1:3306/jeecg-boot?characterEncoding=UTF-8&useUnicode=true&useSSL=false&tinyInt1isBit=false&allowPublicKeyRetrieval=true&serverTimezone=Asia/Shanghai
username: root
password: root
driver-class-name: com.mysql.cj.jdbc.Driver
# 设置 账号数据源配置
account-ds:
driver-class-name: com.mysql.cj.jdbc.Driver
password: root
url: jdbc:mysql://127.0.0.1:3306/jeecg-account?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&rewriteBatchedStatements=true&useSSL=false
username: root
# 设置 订单数据源配置
order-ds:
driver-class-name: com.mysql.cj.jdbc.Driver
password: root
url: jdbc:mysql://127.0.0.1:3306/jeecg-order?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&rewriteBatchedStatements=true&useSSL=false
username: root
# 设置商品 数据源配置
product-ds:
driver-class-name: com.mysql.cj.jdbc.Driver
password: root
url: jdbc:mysql://127.0.0.1:3306/jeecg-product?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&rewriteBatchedStatements=true&useSSL=false
username: root
# 设置默认数据源或者数据源组 默认值即为master
primary: master # 默认指定一个数据源
# 开启对 seata的支持
seata: true5. Seata start
Use jeecg-boot single-mode test, use the default file for seata configuration, no additional configuration is required, just start seata-server.bat directly.
6. Code writing
Project structure
The three entity classes correspond to the following
package org.jeecg.modules.seata.entity;
import lombok.Data;
import java.math.BigDecimal;
import java.util.Date;
@Data
public class Orders {
private Integer id;
private Integer userId;
private Integer productId;
private BigDecimal payAmount;
private Date addTime;
private Date updateTime;
} package org.jeecg.modules.seata.entity;
import lombok.Data;
import java.math.BigDecimal;
import java.util.Date;
@Data
public class Product {
private Integer id;
private String name;
private BigDecimal price;
private Integer stock;
private Date addTime;
private Date updateTime;
} package org.jeecg.modules.seata.entity;
import lombok.Data;
import java.math.BigDecimal;
import java.util.Date;
@Data
public class Account {
private Integer id;
private Integer userId;
private BigDecimal balance;
private Date updateTime;
}The corresponding code of Mapper is as follows
package org.jeecg.modules.seata.mapper;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.jeecg.modules.seata.entity.Product;
@Mapper
public interface ProductMapper {
int deleteByPrimaryKey(Integer id);
int insert(Product record);
int insertSelective(Product record);
Product selectByPrimaryKey(Integer id);
int updateByPrimaryKeySelective(Product record);
int updateByPrimaryKey(Product record);
int reduceStock(@Param("productId") Integer productId, @Param("amount") Integer amount);
} package org.jeecg.modules.seata.mapper;
import org.apache.ibatis.annotations.Mapper;
import org.jeecg.modules.seata.entity.Orders;
@Mapper
public interface OrdersMapper {
int deleteByPrimaryKey(Integer id);
int insert(Orders record);
int insertSelective(Orders record);
Orders selectByPrimaryKey(Integer id);
int updateByPrimaryKeySelective(Orders record);
int updateByPrimaryKey(Orders record);
} package org.jeecg.modules.seata.mapper;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Param;
import org.jeecg.modules.seata.entity.Account;
import java.math.BigDecimal;
@Mapper
public interface AccountMapper {
int deleteByPrimaryKey(Integer id);
int insert(Account record);
int insertSelective(Account record);
Account selectByPrimaryKey(Integer id);
Account selectAccountByUserId(Integer userId);
int updateByPrimaryKeySelective(Account record);
int updateByPrimaryKey(Account record);
int reduceBalance(@Param("userId") Integer userId, @Param("money") BigDecimal money);
} <?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="org.jeecg.modules.seata.mapper.ProductMapper">
<resultMap id="BaseResultMap" type="org.jeecg.modules.seata.entity.Product">
<id column="id" jdbcType="INTEGER" property="id"/>
<result column="name" jdbcType="VARCHAR" property="name"/>
<result column="price" jdbcType="DECIMAL" property="price"/>
<result column="stock" jdbcType="INTEGER" property="stock"/>
<result column="add_time" jdbcType="TIMESTAMP" property="addTime"/>
<result column="update_time" jdbcType="TIMESTAMP" property="updateTime"/>
</resultMap>
<sql id="Base_Column_List">
id, name, price, stock, add_time, update_time
</sql>
<select id="selectByPrimaryKey" parameterType="java.lang.Integer" resultMap="BaseResultMap">
select
<include refid="Base_Column_List"/>
from product
where id = #{id,jdbcType=INTEGER}
</select>
<delete id="deleteByPrimaryKey" parameterType="java.lang.Integer">
delete from product
where id = #{id,jdbcType=INTEGER}
</delete>
<insert id="insert" parameterType="org.jeecg.modules.seata.entity.Product">
insert into product (id, name, price,
stock, add_time, update_time
)
values (#{id,jdbcType=INTEGER}, #{name,jdbcType=VARCHAR}, #{price,jdbcType=DECIMAL},
#{stock,jdbcType=INTEGER}, #{addTime,jdbcType=TIMESTAMP}, #{updateTime,jdbcType=TIMESTAMP}
)
</insert>
<insert id="insertSelective" parameterType="org.jeecg.modules.seata.entity.Product">
insert into product
<trim prefix="(" suffix=")" suffixOverrides=",">
<if test="id != null">
id,
</if>
<if test="name != null">
name,
</if>
<if test="price != null">
price,
</if>
<if test="stock != null">
stock,
</if>
<if test="addTime != null">
add_time,
</if>
<if test="updateTime != null">
update_time,
</if>
</trim>
<trim prefix="values (" suffix=")" suffixOverrides=",">
<if test="id != null">
#{id,jdbcType=INTEGER},
</if>
<if test="name != null">
#{name,jdbcType=VARCHAR},
</if>
<if test="price != null">
#{price,jdbcType=DECIMAL},
</if>
<if test="stock != null">
#{stock,jdbcType=INTEGER},
</if>
<if test="addTime != null">
#{addTime,jdbcType=TIMESTAMP},
</if>
<if test="updateTime != null">
#{updateTime,jdbcType=TIMESTAMP},
</if>
</trim>
</insert>
<update id="updateByPrimaryKeySelective" parameterType="org.jeecg.modules.seata.entity.Product">
update product
<set>
<if test="name != null">
name = #{name,jdbcType=VARCHAR},
</if>
<if test="price != null">
price = #{price,jdbcType=DECIMAL},
</if>
<if test="stock != null">
stock = #{stock,jdbcType=INTEGER},
</if>
<if test="addTime != null">
add_time = #{addTime,jdbcType=TIMESTAMP},
</if>
<if test="updateTime != null">
update_time = #{updateTime,jdbcType=TIMESTAMP},
</if>
</set>
where id = #{id,jdbcType=INTEGER}
</update>
<update id="updateByPrimaryKey" parameterType="org.jeecg.modules.seata.entity.Product">
update product
set name = #{name,jdbcType=VARCHAR},
price = #{price,jdbcType=DECIMAL},
stock = #{stock,jdbcType=INTEGER},
add_time = #{addTime,jdbcType=TIMESTAMP},
update_time = #{updateTime,jdbcType=TIMESTAMP}
where id = #{id,jdbcType=INTEGER}
</update>
<!--减库存-->
<update id="reduceStock">
update product SET stock = stock - #{amount, jdbcType=INTEGER}
WHERE id = #{productId, jdbcType=INTEGER} AND stock >= #{amount, jdbcType=INTEGER}
</update>
</mapper> <?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="org.jeecg.modules.seata.mapper.OrdersMapper">
<resultMap id="BaseResultMap" type="org.jeecg.modules.seata.entity.Orders">
<id column="id" jdbcType="INTEGER" property="id" />
<result column="user_id" jdbcType="INTEGER" property="userId" />
<result column="product_id" jdbcType="INTEGER" property="productId" />
<result column="pay_amount" jdbcType="DECIMAL" property="payAmount" />
<result column="add_time" jdbcType="TIMESTAMP" property="addTime" />
<result column="update_time" jdbcType="TIMESTAMP" property="updateTime" />
</resultMap>
<sql id="Base_Column_List">
id, user_id, product_id, pay_amount, add_time, update_time
</sql>
<select id="selectByPrimaryKey" parameterType="java.lang.Integer" resultMap="BaseResultMap">
select
<include refid="Base_Column_List" />
from orders
where id = #{id,jdbcType=INTEGER}
</select>
<delete id="deleteByPrimaryKey" parameterType="java.lang.Integer">
delete from orders
where id = #{id,jdbcType=INTEGER}
</delete>
<insert id="insert" parameterType="org.jeecg.modules.seata.entity.Orders">
insert into orders (id, user_id, product_id,
pay_amount, add_time, update_time
)
values (#{id,jdbcType=INTEGER}, #{userId,jdbcType=INTEGER}, #{productId,jdbcType=INTEGER},
#{payAmount,jdbcType=DECIMAL}, #{addTime,jdbcType=TIMESTAMP}, #{updateTime,jdbcType=TIMESTAMP}
)
</insert>
<insert id="insertSelective" parameterType="org.jeecg.modules.seata.entity.Orders">
insert into orders
<trim prefix="(" suffix=")" suffixOverrides=",">
<if test="id != null">
id,
</if>
<if test="userId != null">
user_id,
</if>
<if test="productId != null">
product_id,
</if>
<if test="payAmount != null">
pay_amount,
</if>
<if test="addTime != null">
add_time,
</if>
<if test="updateTime != null">
update_time,
</if>
</trim>
<trim prefix="values (" suffix=")" suffixOverrides=",">
<if test="id != null">
#{id,jdbcType=INTEGER},
</if>
<if test="userId != null">
#{userId,jdbcType=INTEGER},
</if>
<if test="productId != null">
#{productId,jdbcType=INTEGER},
</if>
<if test="payAmount != null">
#{payAmount,jdbcType=DECIMAL},
</if>
<if test="addTime != null">
#{addTime,jdbcType=TIMESTAMP},
</if>
<if test="updateTime != null">
#{updateTime,jdbcType=TIMESTAMP},
</if>
</trim>
</insert>
<update id="updateByPrimaryKeySelective" parameterType="org.jeecg.modules.seata.entity.Orders">
update orders
<set>
<if test="userId != null">
user_id = #{userId,jdbcType=INTEGER},
</if>
<if test="productId != null">
product_id = #{productId,jdbcType=INTEGER},
</if>
<if test="payAmount != null">
pay_amount = #{payAmount,jdbcType=DECIMAL},
</if>
<if test="addTime != null">
add_time = #{addTime,jdbcType=TIMESTAMP},
</if>
<if test="updateTime != null">
update_time = #{updateTime,jdbcType=TIMESTAMP},
</if>
</set>
where id = #{id,jdbcType=INTEGER}
</update>
<update id="updateByPrimaryKey" parameterType="org.jeecg.modules.seata.entity.Orders">
update orders
set user_id = #{userId,jdbcType=INTEGER},
product_id = #{productId,jdbcType=INTEGER},
pay_amount = #{payAmount,jdbcType=DECIMAL},
add_time = #{addTime,jdbcType=TIMESTAMP},
update_time = #{updateTime,jdbcType=TIMESTAMP}
where id = #{id,jdbcType=INTEGER}
</update>
</mapper> <?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="org.jeecg.modules.seata.mapper.AccountMapper">
<resultMap id="BaseResultMap" type="org.jeecg.modules.seata.entity.Account">
<id column="id" jdbcType="INTEGER" property="id"/>
<result column="user_id" jdbcType="INTEGER" property="userId"/>
<result column="balance" jdbcType="DECIMAL" property="balance"/>
<result column="update_time" jdbcType="TIMESTAMP" property="updateTime"/>
</resultMap>
<sql id="Base_Column_List">
id, user_id, balance, update_time
</sql>
<!--根据userId-->
<select id="selectAccountByUserId" parameterType="java.lang.Integer" resultMap="BaseResultMap">
select
<include refid="Base_Column_List"/>
from account
where user_id = #{userId, jdbcType=INTEGER}
</select>
<select id="selectByPrimaryKey" parameterType="java.lang.Integer" resultMap="BaseResultMap">
select
<include refid="Base_Column_List"/>
from account
where id = #{id,jdbcType=INTEGER}
</select>
<delete id="deleteByPrimaryKey" parameterType="java.lang.Integer">
delete from account
where id = #{id,jdbcType=INTEGER}
</delete>
<insert id="insert" parameterType="org.jeecg.modules.seata.entity.Account">
insert into account (id, user_id, balance,
update_time)
values (#{id,jdbcType=INTEGER}, #{userId,jdbcType=INTEGER}, #{balance,jdbcType=DOUBLE},
#{updateTime,jdbcType=TIMESTAMP})
</insert>
<insert id="insertSelective" parameterType="org.jeecg.modules.seata.entity.Account">
insert into account
<trim prefix="(" suffix=")" suffixOverrides=",">
<if test="id != null">
id,
</if>
<if test="userId != null">
user_id,
</if>
<if test="balance != null">
balance,
</if>
<if test="updateTime != null">
update_time,
</if>
</trim>
<trim prefix="values (" suffix=")" suffixOverrides=",">
<if test="id != null">
#{id,jdbcType=INTEGER},
</if>
<if test="userId != null">
#{userId,jdbcType=INTEGER},
</if>
<if test="balance != null">
#{balance,jdbcType=DOUBLE},
</if>
<if test="updateTime != null">
#{updateTime,jdbcType=TIMESTAMP},
</if>
</trim>
</insert>
<update id="updateByPrimaryKeySelective" parameterType="org.jeecg.modules.seata.entity.Account">
update account
<set>
<if test="userId != null">
user_id = #{userId,jdbcType=INTEGER},
</if>
<if test="balance != null">
balance = #{balance,jdbcType=DOUBLE},
</if>
<if test="updateTime != null">
update_time = #{updateTime,jdbcType=TIMESTAMP},
</if>
</set>
where id = #{id,jdbcType=INTEGER}
</update>
<update id="updateByPrimaryKey" parameterType="org.jeecg.modules.seata.entity.Account">
update account
set user_id = #{userId,jdbcType=INTEGER},
balance = #{balance,jdbcType=DOUBLE},
update_time = #{updateTime,jdbcType=TIMESTAMP}
where id = #{id,jdbcType=INTEGER}
</update>
<!--减余额-->
<update id="reduceBalance">
update account
SET balance = balance - #{money}
WHERE user_id = #{userId, jdbcType=INTEGER}
AND balance >= ${money}
</update>
</mapper>The code corresponding to the Service is as follows
package org.jeecg.modules.seata.service;
import org.jeecg.modules.seata.entity.Product;
public interface ProductService {
/**
* 减库存
*
* @param productId 商品 ID
* @param amount 扣减数量
* @throws Exception 扣减失败时抛出异常
*/
Product reduceStock(Integer productId, Integer amount) throws Exception;
} package org.jeecg.modules.seata.service;
public interface OrderService {
/**
* 下订单
*
* @param userId 用户id
* @param productId 产品id
* @return 订单id
* @throws Exception 创建订单失败，抛出异常
*/
Integer createOrder(Integer userId, Integer productId) throws Exception;
} package org.jeecg.modules.seata.service;
import java.math.BigDecimal;
public interface AccountService {
/**
* 减余额
*
* @param userId 用户id
* @param money 扣减金额
* @throws Exception 失败时抛出异常
*/
void reduceBalance(Integer userId, BigDecimal money) throws Exception;
} package org.jeecg.modules.seata.service.impl;
import com.baomidou.dynamic.datasource.annotation.DS;
import io.seata.core.context.RootContext;
import lombok.extern.slf4j.Slf4j;
import org.jeecg.modules.seata.entity.Product;
import org.jeecg.modules.seata.mapper.ProductMapper;
import org.jeecg.modules.seata.service.ProductService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Slf4j
@Service
public class ProductServiceImpl implements ProductService {
@Autowired
private ProductMapper productMapper;
@Override
@DS(value = "product-ds")
public Product reduceStock(Integer productId, Integer amount) throws Exception {
log.info("当前 XID: {}", RootContext.getXID());
// 检查库存
Product product = productMapper.selectByPrimaryKey(productId);
if (product.getStock() < amount) {
throw new Exception("库存不足");
}
// 扣减库存
int updateCount = productMapper.reduceStock(productId, amount);
// 扣除成功
if (updateCount == 0) {
throw new Exception("库存不足");
}
// 扣除成功
log.info("扣除 {} 库存成功", productId);
return product;
}
} package org.jeecg.modules.seata.service.impl;
import com.baomidou.dynamic.datasource.annotation.DS;
import io.seata.core.context.RootContext;
import io.seata.spring.annotation.GlobalTransactional;
import lombok.extern.slf4j.Slf4j;
import org.jeecg.modules.seata.entity.Orders;
import org.jeecg.modules.seata.entity.Product;
import org.jeecg.modules.seata.mapper.OrdersMapper;
import org.jeecg.modules.seata.service.AccountService;
import org.jeecg.modules.seata.service.OrderService;
import org.jeecg.modules.seata.service.ProductService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.math.BigDecimal;
@Slf4j
@Service
public class OrderServiceImpl implements OrderService {
@Autowired
private OrdersMapper ordersMapper;
@Autowired
private AccountService accountService;
@Autowired
private ProductService productService;
@Override
@DS(value = "order-ds")
@GlobalTransactional //seata全局事务注解
public Integer createOrder(Integer userId, Integer productId) throws Exception {
Integer amount = 1; // 购买数量暂时设置为 1
log.info("当前 XID: {}", RootContext.getXID());
// 减库存 - 远程服务
Product product = productService.reduceStock(productId, amount);
// 减余额 - 远程服务
accountService.reduceBalance(userId, product.getPrice());
// 下订单 - 本地下订单
Orders order = new Orders();
order.setUserId(userId);
order.setProductId(productId);
order.setPayAmount(product.getPrice().multiply(new BigDecimal(amount)));
ordersMapper.insertSelective(order);
log.info("下订单: {}", order.getId());
//int a = 1/0;
// 返回订单编号
return order.getId();
}
} package org.jeecg.modules.seata.service.impl;
import com.baomidou.dynamic.datasource.annotation.DS;
import io.seata.core.context.RootContext;
import lombok.extern.slf4j.Slf4j;
import org.jeecg.modules.seata.entity.Account;
import org.jeecg.modules.seata.mapper.AccountMapper;
import org.jeecg.modules.seata.service.AccountService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.math.BigDecimal;
@Slf4j
@Service
public class AccountServiceImpl implements AccountService {
@Autowired
private AccountMapper accountMapper;
@Override
@DS(value = "account-ds")
public void reduceBalance(Integer userId, BigDecimal money) throws Exception {
log.info("当前 XID: {}", RootContext.getXID());
// 检查余额
Account account = accountMapper.selectAccountByUserId(userId);
if (account.getBalance().doubleValue() < money.doubleValue()) {
throw new Exception("余额不足");
}
// 扣除余额
int updateCount = accountMapper.reduceBalance(userId, money);
// 扣除成功
if (updateCount == 0) {
throw new Exception("余额不足");
}
log.info("扣除用户 {} 余额成功", userId);
}
}The code corresponding to the controller is as follows
package org.jeecg.modules.seata.controller;
import lombok.extern.slf4j.Slf4j;
import org.jeecg.modules.seata.service.OrderService;
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;
@Slf4j //lombok
@RestController
public class OrderController {
@Autowired
private OrderService orderService;
@RequestMapping("/order")
public Integer createOrder(@RequestParam("userId") Integer userId,
@RequestParam("productId") Integer productId) throws Exception {
log.info("请求下单, 用户:{}, 商品:{}", userId, productId);
return orderService.createOrder(userId, productId);
}
}7. Test Results
request in browser
http://localhost:8080/jeecg-boot/order?userId=1&productId=1 
Submitted normally, the database data is normal.
http://localhost:8080/jeecg-boot/order?userId=2&productId=1 
The update is abnormal and the data is rolled back.
java
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