使用spring+mybatis+atomikos+tomcat构建分布式事务

本文通过一个demo，介绍如何使用spring+mybatis+atomikos+tomcat构建在一个事务中涉及两个数据源的web应用。

demo功能：实现一个能成功提交和回滚的涉及两个数据库数据源的XA事务。

demo将实现：

1.一次性在两个数据库的两张表中各插入一条数据并提交。

2.一次性在两个数据库的两张表中各插入一条数据并回滚。

测试方式：restful web api

使用工具：

spring 4.1.1.RELEASE

mybatis 3.2.7

atomikos 3.7.0

tomcat 7

在mysql中建立两个schema,分别为dev和qa。并在里面分别建立一张名字表。

schema:dev

table:namaDev

id | nameDev

scheme:qa

table:nameQa

id  |  nameQa

对应的sql为

CREATE SCHEMA `qa` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci ;
CREATE SCHEMA `dev` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci ;

 CREATE  TABLE `dev`.`nameDev` (
  `id` BIGINT NOT NULL AUTO_INCREMENT ,
  `nameDev` VARCHAR(45) NULL ,
  PRIMARY KEY (`id`) ,
  UNIQUE INDEX `id_UNIQUE` (`id` ASC) );

  CREATE  TABLE `qa`.`nameQa` (
  `id` BIGINT NOT NULL AUTO_INCREMENT ,
  `nameQa` VARCHAR(45) NULL ,
  PRIMARY KEY (`id`) ,
  UNIQUE INDEX `id_UNIQUE` (`id` ASC) );

代码分析：

本项目使用spring框架，因此首先配置相关bean

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context"
       xmlns:tx="http://www.springframework.org/schema/tx" xmlns:jdbc="http://www.springframework.org/schema/jdbc"
       xmlns:rabbit="http://www.springframework.org/schema/rabbit"
       xmlns:cache="http://www.springframework.org/schema/cache" xmlns:task="http://www.springframework.org/schema/task"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc.xsd http://www.springframework.org/schema/rabbit http://www.springframework.org/schema/rabbit/spring-rabbit.xsd
       http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task.xsd">
    <context:component-scan base-package="com.xy">
        <context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
    </context:component-scan>
    <context:property-placeholder location="classpath:context/database.properties"/>
    <tx:annotation-driven/>

    <bean id="abstractXADataSource" class="com.atomikos.jdbc.AtomikosDataSourceBean" init-method="init"
          destroy-method="close" abstract="true">
        <property name="xaDataSourceClassName" value="com.mysql.jdbc.jdbc2.optional.MysqlXADataSource"/>
        <property name="poolSize" value="10" />
        <property name="minPoolSize" value="10"/>
        <property name="maxPoolSize" value="30"/>
        <property name="borrowConnectionTimeout" value="60"/>
        <property name="reapTimeout" value="20"/>
        <!-- 最大空闲时间 -->
        <property name="maxIdleTime" value="60"/>
        <property name="maintenanceInterval" value="60"/>
        <property name="loginTimeout" value="60"/>
        <property name="testQuery">
            <value>select 1</value>
        </property>
    </bean>
    
    <bean id="qadataSource" parent="abstractXADataSource">
        <!-- value只要两个数据源不同就行，随便取名 -->
        <property name="uniqueResourceName" value="mysql/sitestone1" />
        <property name="xaDataSourceClassName"
                  value="com.mysql.jdbc.jdbc2.optional.MysqlXADataSource" />
        <property name="xaProperties">
            <props>
                <prop key="URL">${qa.db.url}</prop>
                <prop key="user">${qa.db.user}</prop>
                <prop key="password">${qa.db.password}</prop>
                <prop key="pinGlobalTxToPhysicalConnection">true</prop>
            </props>
        </property>
    </bean>

    <bean id="devdataSource" parent="abstractXADataSource">
        <!-- value只要两个数据源不同就行，随便取名 -->
        <property name="uniqueResourceName" value="mysql/sitestone" />
        <property name="xaDataSourceClassName"
                  value="com.mysql.jdbc.jdbc2.optional.MysqlXADataSource" />
        <property name="xaProperties">
            <props>
                <prop key="URL">${dev.db.url}</prop>
                <prop key="user">${dev.db.user}</prop>
                <prop key="password">${dev.db.password}</prop>
                <prop key="pinGlobalTxToPhysicalConnection">true</prop>
            </props>
        </property>
    </bean>



    <bean id="qasqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="qadataSource" />
        <property name="mapperLocations" value="classpath*:com/xy/dao/*.xml" />
    </bean>

    <bean id="devsqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="devdataSource" />
        <property name="mapperLocations" value="classpath*:com/xy/daodev/*.xml" />
    </bean>

    <bean id="atomikosTransactionManager" class="com.atomikos.icatch.jta.UserTransactionManager"
          init-method="init" destroy-method="close">
        <property name="forceShutdown">
            <value>true</value>
        </property>
    </bean>
    <bean id="atomikosUserTransaction" class="com.atomikos.icatch.jta.UserTransactionImp">
        <property name="transactionTimeout" value="300" />
    </bean>

    <bean id="transactionManager"
          class="org.springframework.transaction.jta.JtaTransactionManager">
        <property name="transactionManager">
            <ref bean="atomikosTransactionManager"/>
        </property>
        <property name="userTransaction">
            <ref bean="atomikosUserTransaction"/>
        </property>
        <!-- 必须设置，否则程序出现异常 JtaTransactionManager does not support custom isolation levels by default -->
        <property name="allowCustomIsolationLevels" value="true"/>

    </bean>



    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.xy.dao"/>
        <property name="sqlSessionFactoryBeanName" value="qasqlSessionFactory" />
    </bean>

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="basePackage" value="com.xy.daodev"/>
        <property name="sqlSessionFactoryBeanName" value="devsqlSessionFactory" />
    </bean>
</beans>

 其中qadataSource和devdataSource是对应两个数据库的数据源，qasqlSessionFactory和devsqlSessionFactory是mybatis的sessionfactory,两个MapperScannerConfigurer自动将不同数据源的sql语句文件与interface自动装配起来，atomikosTransactionManager会自动管理两个atomikos的数据源的事务，即resource manager，atomikosUserTransaction为最上层的事务管理器为transaction manager。(关于RM和TM，请参见上篇博文)。

Model类如下：package com.xy.model

package com.xy.model;

/**
 * Created by helloworld on 2015/1/30.
 */
public class NameQa {
    private long id;
    private String nameQa;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getNameQa() {
        return nameQa;
    }

    public void setNameQa(String nameQa) {
        this.nameQa = nameQa;
    }
}

package com.xy.model;

/**
 * Created by helloworld on 2015/1/30.
 */
public class NameDev {
    private long id;
    private String nameDev;

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public String getNameDev() {
        return nameDev;
    }

    public void setNameDev(String nameDev) {
        this.nameDev = nameDev;
    }
}

qa数据源的mybatis mapper接口 package com.xy.dao

package com.xy.dao;

import com.xy.model.NameQa;

/**
 * Created by helloworld on 2015/1/30.
 */
public interface NameQaMapper {
    int insert(NameQa nameQa);
}

dev数据源的mybatis mapper接口 package com.xy.devdao

package com.xy.daodev;

import com.xy.model.NameDev;

/**
 * Created by helloworld on 2015/1/30.
 */
public interface NameDevMapper {
    int insert(NameDev nameDev);
}

处理事务的service

package com.xy.service;

import com.xy.dao.NameQaMapper;
import com.xy.daodev.NameDevMapper;
import com.xy.model.NameDev;
import com.xy.model.NameQa;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

/**
 * Created by helloworld on 2015/1/30.
 */
@Service
public class NameService {
    @Autowired
    NameQaMapper nameQaMapper;
    @Autowired
    NameDevMapper nameDevMapper;

    @Transactional(rollbackFor = Exception.class)
    public void addQaAndDev(boolean hasException) throws Exception {
        NameQa nameQa = new NameQa();
        nameQa.setNameQa("qa");
        nameQaMapper.insert(nameQa);

        NameDev nameDev = new NameDev();
        nameDev.setNameDev("dev");
        nameDevMapper.insert(nameDev);

        if(hasException) {
            throw new Exception();
        }
    }


}

controller代码

package com.xy.controller;

import com.xy.service.NameService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

/**
 * Created by helloworld on 2014/11/22.
 */
@Controller
public class mybatisController {

    @Autowired
    NameService nameService;

    @RequestMapping(value = "/addName", method = RequestMethod.POST)
    ModelMap addName(@RequestParam("hasException") boolean hasException) {
        try {
            nameService.addQaAndDev(hasException);
        } catch (Exception e) {
            e.printStackTrace();
            return new ModelMap("false");
        }
        return new ModelMap("true");
    }


}

将项目打成war包，命名为mybatis.war部署在tomcat上。

测试：

1.POST  http://localhost:8080/mybatis/addName.json

request parameters: hasException=false

返回：true 数据添加成功

2.POST  http://localhost:8080/mybatis/addName.json

　request parameters: hasException=true

返回：false 两个数据库数据都未添加

源码下载：https://files.cnblogs.com/files/rain-in-sun/springmvc-mybatis-atomikos.rar