springboot-jta

背景

我们平时在用springboot开发时，要使用事务，只需要在方法上添加@Transaction注解即可，但这种方式只适用单数据源，在多数据源下就不再适用；

比如在多数据源下，我们在一个方法里执行了数据源A的操作，又执行了数据源B的操作，如果报错了，事务只会回滚主数据源或者是指定事务的数据源数据（@Transactional(value=”指定事务”)），另一个数据源是不会回滚的；

这种情况下，单纯的@Transactional事务注解是无法实现的，此时就需要用到多数据源事务管理；

以下项目里实现了普通情况下的事务处理和使用springboot-jta-atomikos事务处理

本文主要介绍使用springboot-jta-atomikos来实现；

源码地址

https://github.com/lvlq73/springboot-jta-atomikos

项目目录结构

 实现

1.添加依赖 pom.xml

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

2.配置数据库连接信息 application.properties

#atomikos测试
spring.datasource.test1.url=jdbc:mysql://127.0.0.1:3306/test1?allowMultiQueries=true&useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=UTC&zeroDateTimeBehavior=CONVERT_TO_NULL&serverTimezone=Asia/Shanghai
spring.datasource.test1.user=root
spring.datasource.test1.password=arsenal

spring.datasource.test2.url=jdbc:mysql://127.0.0.1:3306/test2?allowMultiQueries=true&useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=UTC&zeroDateTimeBehavior=CONVERT_TO_NULL&serverTimezone=Asia/Shanghai
spring.datasource.test2.user=root
spring.datasource.test2.password=arsenal

3.创建多数据源 DBAtomikosConfig.java

package com.llq.atomikos.config;

import com.atomikos.icatch.jta.UserTransactionImp;
import com.atomikos.icatch.jta.UserTransactionManager;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.boot.jta.atomikos.AtomikosDataSourceBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.transaction.jta.JtaTransactionManager;

import javax.sql.DataSource;
import javax.transaction.UserTransaction;
import java.util.Properties;

/**
 * @author lvlianqi
 * @description
 * @date 2022/3/7
 */
@Configuration
public class DBAtomikosConfig {

    //--------------------数据源1--------------------
    @ConfigurationProperties(prefix = "spring.datasource.test1")
    @Bean
    public Properties testOneProperties() {
        return new Properties();
    }

    @Bean(name = "testOneDataSource")
    @Primary
    public DataSource testOneDataSource() {
        AtomikosDataSourceBean ds = new AtomikosDataSourceBean();
        Properties prop = testOneProperties();
        ds.setXaDataSourceClassName("com.mysql.cj.jdbc.MysqlXADataSource");
        ds.setUniqueResourceName("testOne");
        ds.setXaProperties(prop);
        return ds;
    }

    @Bean
    @Primary
    public JdbcTemplate testOneJdbcTemplate(@Qualifier("testOneDataSource") DataSource dataSource) {
        return new JdbcTemplate(dataSource);
    }

    //--------------------数据源2--------------------
    @ConfigurationProperties(prefix = "spring.datasource.test2")
    @Bean
    public Properties testTwoProperties() {
        return new Properties();
    }

    @Bean(name = "testTwoDataSource")
    public DataSource testTwoDataSource() {
        AtomikosDataSourceBean ds = new AtomikosDataSourceBean();
        Properties prop = testTwoProperties();
        ds.setXaDataSourceClassName("com.mysql.cj.jdbc.MysqlXADataSource");
        ds.setUniqueResourceName("testTwo");
        ds.setXaProperties(prop);
        return ds;
    }

    @Bean
    public JdbcTemplate testTwoJdbcTemplate(@Qualifier("testTwoDataSource") DataSource dataSource) {
        return new JdbcTemplate(dataSource);
    }
    //--------------------配置spring的JtaTransactionManager，底层委派给atomikos进行处理--------------------
    @Bean
    public JtaTransactionManager jtaTransactionManager () {
        UserTransactionManager userTransactionManager = new UserTransactionManager();
        UserTransaction userTransaction = new UserTransactionImp();
        return new JtaTransactionManager(userTransaction, userTransactionManager);
    }
}

4.测试事务类 TestAtomikos.java

package com.llq.atomikos.service;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

/**
 * @author lvlianqi
 * @description
 * @date 2022/3/7
 */
@Service
public class TestAtomikos implements ITest{

    @Qualifier("testOneJdbcTemplate")
    @Autowired
    private JdbcTemplate testOneJdbcTemplate;

    @Qualifier("testTwoJdbcTemplate")
    @Autowired
    private JdbcTemplate testTwoJdbcTemplate;

    /**
     * 测试正常情况
     */
    @Transactional(rollbackFor = Exception.class, value = "jtaTransactionManager")
    public void test() {
        testOneJdbcTemplate.execute("insert into user (name, age) values ("张三", 18);");
        testTwoJdbcTemplate.execute("insert into user (name, age) values ("李四", 20);");
    }

    /**
     * 测试异常情况
     */
    @Transactional(rollbackFor = Exception.class, value = "jtaTransactionManager")
    public void testByException() {
        testOneJdbcTemplate.execute("insert into user (name, age) values ("张三", 18);");
        testTwoJdbcTemplate.execute("insert into user (name, age) values ("李四", 20);");
        int i = 1/0;
    }
}

5.测试 SpringbootAtomikosApplicationTests.java

    //使用atomikos
    private static Class CLS = TestAtomikos.class;

    @Autowired
    ApplicationContext applicationContext;

    @Test
    public void testByException() {
        ITest test = (ITest) applicationContext.getBean(CLS);
        test.testByException();
    }

测试结果

执行错误

数据库test1 user表没有记录

数据库test2 user表没有记录