blog迁移至 :http://www.micmiu.com
在2011.7.1号这个特殊的日子,发一blog,名为:分布式事务JTA之实践:Spring+ATOMIKOS 来庆祝党的90岁生日和iteye博客产品成功改版上线。
本文的目录结构如下:
- 一、概述
- 二、应用场景
- 三、实验模拟需求
- 四、实例测试 环境
- 五、 源代码下载 及配置介绍
- 六、测试验证
一、概述:
本文主要讲述如何基于Atomikos 和 spring 在项目中实现分布式事务管理
二、应用场景:
如果项目中的数据源来自多个数据库,同时又需要在多数据源中保证事务,此时就需要用到分布式事务处理了。
三、实验模拟需求 :
比如有两个对象:用户信息、用户存款,用户信息存在数据库A、存款信息存在数据库B,若客户甲向乙转账,需要在数据库B中对甲、乙的存款信息修改,同时在数据库A中把甲、乙的备注信息最新为最近一次的操作时间。
四 、实例测试环境 :
- spring、hibernate3.2
- mysql5.1.51(需要版本5.0+)
- AtomikosTransactionsEssentials-3.7.0 (详细可参加它的官网:http://www.atomikos.com )
说明:
1. 测试的数据库需要支持分布式事务,同时JDBC要支持XA 连接驱动 。本次测试用的mysql5.1是支持事务的,JDBC驱动版本:mysql-connector-java-5.1.7-bin.jar,包含对 XA连接的支持:com.mysql.jdbc.jdbc2.optional.MysqlXAConnection。
2. 附件提供AtomikosTransactionsEssentials 3.7.0 lib包下载 :AtomikosTransactionsEssentials-3.7.0-lib.zip
官方下载地址:http://www.atomikos.com/Main/TransactionsEssentialsDownloadForm ,需要先注册才能下载。同时这里也提供目前3.7.0的下载链接:http://www.atomikos.com/downloads/transactions-essentials/com/atomikos/AtomikosTransactionsEssentials/3.7.0/AtomikosTransactionsEssentials-3.7.0-bin.zip
五、代码及配置介绍:
源代码下载 :分布式事务实例演示源代码
1.代码的目录结构图如下:
转账测试的的代码片段:
/**
* 转账测试
* @param srcId
* @param destId
* @param money
* @return boolean
*/
public boolean doTestTransfer(String srcId, String destId, float money) {
BankAccount srcAccount = bankAccountDao.getByUserName(srcId);
BankAccount destAccount = bankAccountDao.getByUserName(destId);
if (srcAccount.getDeposit() < money) {
System.out.println("warn :" + srcAccount.getUserName()
+ " has not enough money to transfer");
return false;
}
srcAccount.setDeposit(srcAccount.getDeposit() - money);
destAccount.setDeposit(destAccount.getDeposit() + money);
// 把更新存款信息置于异常发生之前
bankAccountDao.update(srcAccount);
bankAccountDao.update(destAccount);
Date curTime = new Date();
UserInfo srcUser = userInfoDao.getById(srcId);
UserInfo destUser = userInfoDao.getById(destId);
destUser.setRemark1(curTime + "");
destUser.setRemark2(curTime + "");
// 把更新基本信息置于异常发生之前
userInfoDao.update(destUser);
srcUser.setRemark1(curTime + "");
if (srcAccount.getDeposit() < 18000) {
throw new RuntimeException("michael test exception for JTA ");
}
srcUser.setRemark2(curTime + "");
userInfoDao.update(srcUser);
System.out.println("success done:" + srcAccount.getUserName()
+ " transfer ¥" + money + " to " + destAccount.getUserName());
return true;
}
2. 配置文件详细介绍:
jta.jdbc.properties
#see http://sjsky.iteye.com
# eg. for mysql
jdbc.SDS.class=com.mysql.jdbc.jdbc2.optional.MysqlXADataSource
jdbc.SDS.properties=URL=jdbc:mysql://192.168.8.253:3306/demota;user=root;password=111111
jdbc.SDS2.class=com.mysql.jdbc.jdbc2.optional.MysqlXADataSource
jdbc.SDS2.properties=URL=jdbc:mysql://192.168.8.150:3306/demota;user=root;password=111111
jta.properties
#see http://sjsky.iteye.com
com.atomikos.icatch.service=com.atomikos.icatch.standalone.UserTransactionServiceFactory
com.atomikos.icatch.console_file_name = tm.out
com.atomikos.icatch.log_base_name = tmlog
com.atomikos.icatch.tm_unique_name = com.atomikos.spring.jdbc.tm
com.atomikos.icatch.console_log_level = INFO
jta1.hibernate.cfg.xml
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <property name="dialect"> org.hibernate.dialect.MySQL5Dialect </property> <property name="hbm2ddl.auto">update</property> <mapping class="michael.jta.atomikos.domain.UserInfo" /> </session-factory> </hibernate-configuration>
jta2.hibernate.cfg.xml
<!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory> <property name="show_sql">true</property> <property name="dialect"> org.hibernate.dialect.MySQL5Dialect </property> <property name="hbm2ddl.auto">update</property> <mapping class="michael.jta.atomikos.domain.BankAccount" /> </session-factory> </hibernate-configuration>
jta.spring.xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN" "http://www.springframework.org/dtd/spring-beans.dtd"> <beans> <!-- Configurer that replaces ${...} placeholders with values from properties files --> <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="locations"> <list> <value>classpath:jta.jdbc.properties</value> </list> </property> </bean> <!-- 数据源配置 http://sjsky.iteye.com--> <bean id="SDS" class="com.atomikos.jdbc.SimpleDataSourceBean" init-method="init" destroy-method="close"> <property name="uniqueResourceName"> <value>SDS</value> </property> <property name="xaDataSourceClassName"> <value>${jdbc.SDS.class}</value> </property> <property name="xaDataSourceProperties"> <value>${jdbc.SDS.properties}</value> </property> <property name="exclusiveConnectionMode"> <value>true</value> </property> <property name="connectionPoolSize"> <value>3</value> </property> <property name="validatingQuery"> <value>SELECT 1</value> </property> </bean> <bean id="SDS2" class="com.atomikos.jdbc.SimpleDataSourceBean" init-method="init" destroy-method="close"> <property name="uniqueResourceName"> <value>SDS2</value> </property> <property name="xaDataSourceClassName"> <value>${jdbc.SDS2.class}</value> </property> <property name="xaDataSourceProperties"> <value>${jdbc.SDS2.properties}</value> </property> <property name="exclusiveConnectionMode"> <value>true</value> </property> <property name="connectionPoolSize"> <value>3</value> </property> <property name="validatingQuery"> <value>SELECT 1</value> </property> </bean> <!-- sessionFactory http://sjsky.iteye.com--> <bean id="sessionFactory1" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"> <property name="dataSource" ref="SDS" /> <property name="configLocation" value="classpath:jta1.hibernate.cfg.xml" /> </bean> <bean id="sessionFactory2" class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean"> <property name="dataSource" ref="SDS2" /> <property name="configLocation" value="classpath:jta2.hibernate.cfg.xml" /> </bean> <!-- TransactionManager http://sjsky.iteye.com--> <!-- Construct Atomikos UserTransactionManager, needed to configure Spring --> <bean id="atomikosTransactionManager" class="com.atomikos.icatch.jta.UserTransactionManager" init-method="init" destroy-method="close"> <!-- when close is called, should we force transactions to terminate or not? --> <property name="forceShutdown"> <value>true</value> </property> </bean> <!-- Also use Atomikos UserTransactionImp, needed to configure Spring --> <bean id="atomikosUserTransaction" class="com.atomikos.icatch.jta.UserTransactionImp"> <property name="transactionTimeout"> <value>300</value> </property> </bean> <!-- Configure the Spring framework to use JTA transactions from Atomikos --> <bean id="springJTATransactionManager" class="org.springframework.transaction.jta.JtaTransactionManager"> <property name="transactionManager"> <ref bean="atomikosTransactionManager" /> </property> <property name="userTransaction"> <ref bean="atomikosUserTransaction" /> </property> </bean> <!-- Configure DAO http://sjsky.iteye.com--> <bean id="userInfoDao" class="michael.jta.atomikos.dao.impl.UserInfoDaoImpl"> <property name="sessionFactory" ref="sessionFactory1" /> </bean> <bean id="bankAccountDao" class="michael.jta.atomikos.dao.BankAccountDao"> <property name="sessionFactory" ref="sessionFactory2" /> </bean> <bean id="bankAccountService" class="michael.jta.atomikos.service.impl.BankAccountServiceImpl"> <property name="userInfoDao" ref="userInfoDao" /> <property name="bankAccountDao" ref="bankAccountDao" /> </bean> <!-- 定义事务规则的拦截器 http://sjsky.iteye.com--> <bean id="transactionInterceptor" class="org.springframework.transaction.interceptor.TransactionInterceptor"> <property name="transactionManager" ref="springJTATransactionManager" /> <property name="transactionAttributes"> <props> <prop key="*">PROPAGATION_REQUIRED</prop> </props> </property> </bean> <!-- 声明式事务边界配置 所有的bean公用一个代理bean http://sjsky.iteye.com--> <bean id="baseTransactionProxy" class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean" abstract="true"> <property name="transactionManager" ref="springJTATransactionManager" /> <property name="transactionAttributes"> <props> <!-- 可以根据实际情况细化配置提高性能 --> <prop key="*">PROPAGATION_REQUIRED</prop> </props> </property> </bean> <bean id="bankAccountServiceProxy" parent="baseTransactionProxy"> <property name="target"> <ref bean="bankAccountService" /> </property> </bean> </beans>
六、测试验证
1. 初始化数据:
因为mysql数据库表的类型有事务和非事务之分,建表时一定要注意确保表的类型是事务控制的:InnoDB
数据库A(192.168.8.253):
DROP DATABASE IF EXISTS demota;
CREATE DATABASE demota;
USE demota;
DROP TABLE IF EXISTS tb_user_info;
CREATE TABLE tb_user_info (
user_name varchar(20),
real_name varchar(10),
remark1 varchar(50),
remark2 varchar(50)
) ENGINE = InnoDB;
INSERT INTO tb_user_info (user_name,real_name,remark1,remark2) VALUES ('husband','husband','','');
INSERT INTO tb_user_info (user_name,real_name,remark1,remark2) VALUES ('wife','wife','','');
数据库B(192.168.8.150):
DROP DATABASE IF EXISTS demota;
CREATE DATABASE demota;
USE demota;
DROP TABLE IF EXISTS tb_account;
CREATE TABLE tb_account (
id int AUTO_INCREMENT,
user_name varchar(20),
deposit float(10,2),
PRIMARY KEY(id)
) ENGINE = InnoDB;
INSERT INTO tb_account (user_name,deposit) VALUES ('husband',20000.00);
INSERT INTO tb_account (user_name,deposit) VALUES ('wife',10000.00);
2. 测试过程:
ps: 代码中模拟了异常出现的条件:如果账户金额<18000会抛出异常
JtaRunMainTest.java
package michael.jta.atomikos;
import michael.jta.atomikos.service.BankAccountService;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
/**
* @author michael
*
*/
public class JtaRunMainTest {
/**
* @param args
*/
public static void main(String[] args) {
System.out.println("------------start");
ApplicationContext appCt = new ClassPathXmlApplicationContext(
"jta.spring.xml");
System.out.println("------------finished init xml");
Object bean = appCt.getBean("bankAccountServiceProxy");
System.out.println(bean.getClass());
BankAccountService service = (BankAccountService) bean;
service.doTestTransfer("husband", "wife", 2000);
}
}
运行第一次结果:
------------finished init xml
class $Proxy11
Hibernate: select bankaccoun0_.id as id2_, bankaccoun0_.deposit as deposit2_, bankaccoun0_.user_name as user3_2_ from tb_account bankaccoun0_ where bankaccoun0_.user_name=?
Hibernate: select bankaccoun0_.id as id2_, bankaccoun0_.deposit as deposit2_, bankaccoun0_.user_name as user3_2_ from tb_account bankaccoun0_ where bankaccoun0_.user_name=?
success done:husband transfer ¥2000.0 to wife
Hibernate: update tb_account set deposit=?, user_name=? where id=?
Hibernate: update tb_account set deposit=?, user_name=? where id=?
运行第二次结果:
------------finished init xml
class $Proxy11
Hibernate: select bankaccoun0_.id as id2_, bankaccoun0_.deposit as deposit2_, bankaccoun0_.user_name as user3_2_ from tb_account bankaccoun0_ where bankaccoun0_.user_name=?
Hibernate: select bankaccoun0_.id as id2_, bankaccoun0_.deposit as deposit2_, bankaccoun0_.user_name as user3_2_ from tb_account bankaccoun0_ where bankaccoun0_.user_name=?
Exception in thread "main" java.lang.RuntimeException: michael test exception for JTA
at michael.jta.atomikos.service.impl.BankAccountServiceImpl.doTestTransfer(BankAccountServiceImpl.java:51)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:299)
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:172)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:139)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:107)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:161)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:202)
at $Proxy11.doTestTransfer(Unknown Source)
at michael.jta.atomikos.JtaRunMainTest.main(JtaRunMainTest.java:26)
测试过程中数据库查询的结果截图:
从上面的数据库截图可见,第一正常运行时两个数据库同步更新了,第二次运行发生异常后,两个数据库的数据为发生变化,实现了事务回滚。
转载请注明来自:Michael's blog @ http://sjsky.iteye.com
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