Spring 中集成 JOTM 配置 JTA 事务:
假如业务中要用到多个数据库,我们希望在业务方法中,当对某一个数据库的数据表进行操作的事务失败并回退(rollback),另外某一个数据库的数据表的操作事务也要回退,但应用一般的事务管理达不到这样的事务管理效果,这就需要实现 JTA 事务管理了。
这里我们在SPring中集成 Object web 的一个开源JTA实现JOTM (可以在http://jotm.objectweb.org下载完整版) 来实现JTA事务管理。
1、将必须的类包放入类路径中:
jotm.jar, xapool.jar, jotm_jrmp_stubs.jar, jta-spect1_0_1.jar, connector-1_5.jar等等。
2、编写JOTM配置文件carol.properties,将其放到类路径下:
- #JNDI调用协议
- carol.protocols=jrmp
- #不使用CAROL JNDI封装器
- carol.start.jndi=false
- #不启动命名服务器
- carol.start.ns=false
3、在MYSQL中创建两个数据库 "jtatesta","jtatestb":
- CREATE DATABASE IF NOT EXISTS jtatesta;
- USE jtatesta;
- DROP TABLE IF EXISTS `user`;
- CREATE TABLE `user` (
- `user_id` int(10) unsigned NOT NULL auto_increment,
- `user_name` varchar(45) NOT NULL,
- `user_password` varchar(45) NOT NULL,
- PRIMARY KEY (`user_id`)
- ) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=latin1;
- INSERT INTO `user` (`user_id`,`user_name`,`user_password`) VALUES
- (1,'tufu','tufu');
- CREATE DATABASE IF NOT EXISTS jtatestb;
- USE jtatestb;
- DROP TABLE IF EXISTS `grade`;
- CREATE TABLE `grade` (
- `grade_id` int(10) unsigned NOT NULL auto_increment,
- `user_id` int(10) unsigned NOT NULL,
- `grade` double NOT NULL,
- PRIMARY KEY (`grade_id`)
- ) ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=latin1;
- INSERT INTO `grade` (`grade_id`,`user_id`,`grade`) VALUES
- (1,0,100);
4、域对象、数据访问类和其他事务管理的一样,如:
- //Domain对象User.java:
- package com.domain;
- import java.io.Serializable;
- public class User implements Serializable {
- private int user_id;
- private String user_name;
- private String user_password;
- ......//省略set、get方法
- }
- //Domain对象Grade.java:
- package com.domain;
- import java.io.Serializable;
- public class Grade implements Serializable{
- private int grade_id;
- private User user;
- private double grade;
- .....//省略set、get方法
- }
- 应用Spring JDBC的DAO:(省略DAO接口)
- //UserJdbcDao.java:
- package com.dao.jdbc;
- import org.springframework.jdbc.core.support.JdbcDaoSupport;
- import com.dao.UserDao;
- import com.domain.User;
- public class UserJdbcDao extends JdbcDaoSupport implements UserDao{
- public void addUser(User user){
- String SQL = "INSERT INTO user(user_id,user_name,user_password) VALUES(?,?,?)";
- Object[] params = new Object[]{
- user.getUser_id(),user.getUser_name(),user.getUser_password()
- };
- this.getJdbcTemplate().update(SQL, params);
- }
- }
- //GradeJdbcDao.java:
- package com.dao.jdbc;
- import com.dao.GradeDao;
- import com.domain.Grade;
- import org.springframework.jdbc.core.support.JdbcDaoSupport;
- public class GradeJdbcDao extends JdbcDaoSupport implements GradeDao{
- public void addGrade(Grade grade){
- final String SQL = "INSERT INTO grade(user_id,grade) VALUES(?,?)";
- Object[] params = new Object[]{
- grade.getUser().getUser_id(),grade.getGrade()
- };
- this.getJdbcTemplate().update(SQL, params);
- }
- }
5、应用了JTA事务管理的业务类(省略了接口),用@Transactional注解标注,以在配置文件中可以用<tx:annotation-driven>注解驱动自动进行事务增强:
- package com.service.impl;
- import com.dao.GradeDao;
- import com.dao.UserDao;
- import com.domain.*;
- import org.springframework.transaction.annotation.Transactional;
- import com.service.MyService;
- @Transactional
- public class MyServiceImpl implements MyService {
- private UserDao userDao;
- private GradeDao gradeDao;
- public void setUserDao(UserDao userDao){
- this.userDao = userDao;
- }
- public void setGradeDao(GradeDao gradeDao){
- this.gradeDao = gradeDao;
- }
- @Transactional(readOnly=false)
- public void addGrade(User user,Grade grade){
- //假如希望两个添加数据的事务,其中有一个添加失败时,均回滚,
- //由于两个操作是在两个不同的数据库上进行的,故要JTA事务来进行管理
- //否则,将会出现添加一个,回滚一个的情形
- gradeDao.addGrade(grade);
- userDao.addUser(user);
- }
- }
6、spring为JOTM提供了一个org.springframework.transaction.jta.JotmFactoryBean 支持类,可以用其方便地创建本地JOTM实例。
具体的配置文件app_jta.xml如下:
- <?xml version="1.0" encoding="UTF-8"?>
- <beans xmlns="http://www.springframework.org/schema/beans"
- xmlns:xsp="http://www.w3.org/2001/XMLSchema-instance"
- xmlns:aop="http://www.springframework.org/schema/aop"
- xmlns:tx="http://www.springframework.org/schema/tx"
- xsp:schemaLocation="http://www.springframework.org/schema/beans
- http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
- http://www.springframework.org/schema/aop
- http://www.springframework.org/schema/aop/spring-aop-2.0.xsd
- http://www.springframework.org/schema/tx
- http://www.springframework.org/schema/tx/spring-tx-2.0.xsd">
- <!--JOTM本地实例-->
- <bean id="jotm" class="org.springframework.transaction.jta.JotmFactoryBean"/>
- <!--JTA事务管理器-->
- <bean id="txManager" class="org.springframework.transaction.jta.JtaTransactionManager">
- <property name="userTransaction" ref="jotm"/><!--指定userTransaction属性引用JOTM本地实例-->
- </bean>
- <!--XAPool配置,内部包含了一XA数据源,对应了数据库jtatesta
- 支持JTA事务的数据源,必须封装成XAPool-->
- <bean id="jtaTestADS" class="org.enhydra.jdbc.pool.StandardXAPoolDataSource"
- destroy-method="shutdown">
- <property name="dataSource"><!--内部XA数据源-->
- <bean class="org.enhydra.jdbc.standard.StandardXADataSource"
- destroy-method="shutdown">
- <property name="transactionManager" ref="jotm"/>
- <property name="driverName" value="com.mysql.jdbc.Driver"/>
- <property name="url" value="jdbc:mysql://localhost/jtatesta"/>
- </bean>
- </property>
- <property name="user" value="root"/>
- <property name="password" value="885123"/>
- </bean>
- <!--类似地,对应了数据库jtatestb的XAPool配置,内部包含了一XA数据源-->
- <bean id="jtaTestBDS" class="org.enhydra.jdbc.pool.StandardXAPoolDataSource"
- destroy-method="shutdown">
- <property name="dataSource"><!--内部XA数据源-->
- <bean class="org.enhydra.jdbc.standard.StandardXADataSource"
- destroy-method="shutdown">
- <property name="transactionManager" ref="jotm"/>
- <property name="driverName" value="com.mysql.jdbc.Driver"/>
- <property name="url" value="jdbc:mysql://localhost/jtatestb"/>
- </bean>
- </property>
- <property name="user" value="root"/>
- <property name="password" value="885123"/>
- </bean>
- <!--分别配置访问jtaTestADS、jtaTestBDS数据源的Spring JDBC模板-->
- <bean id="jtaTestATemplate" class="org.springframework.jdbc.core.JdbcTemplate">
- <property name="dataSource" ref="jtaTestADS"/>
- </bean>
- <bean id="jtaTestBTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
- <property name="dataSource" ref="jtaTestBDS"/>
- </bean>
- <!--分别配置基于模板jtaTestADS,jtaTestBDS的DAO-->
- <bean id="userDao" class="com.dao.jdbc.UserJdbcDao">
- <property name="jdbcTemplate" ref="jtaTestATemplate"/>
- </bean>
- <bean id="gradeDao" class="com.dao.jdbc.GradeJdbcDao">
- <property name="jdbcTemplate" ref="jtaTestBTemplate"/>
- </bean>
- <!--跨数据库的JTA事务的业务类-->
- <bean id="myService" class="com.service.impl.MyServiceImpl">
- <property name="userDao" ref="userDao"/>
- <property name="gradeDao" ref="gradeDao"/>
- </bean>
- <!--注解事务驱动-->
- <tx:annotation-driven transaction-manager="txManager" proxy-target-class="true"/>
- </beans>
7、测试main方法:
- import com.service.MyService;
- import com.service.impl.MyServiceImpl;
- import com.domain.*;
- import org.springframework.context.support.ClassPathXmlApplicationContext;
- public class TestMain {
- public static void main(String args[]){
- ClassPathXmlApplicationContext ctx =
- new ClassPathXmlApplicationContext("beans_jta.xml");
- MyService ms = (MyServiceImpl)ctx.getBean("myService");
- User user = new User();
- //特意添加一个重复的主键,以使添加user的事务失败并回退
- //如果此时应用JTA事务失败,将仍会执行添加grade的事务并提交(前提是先于添加user操作)
- //如果应用JTA事务成功,就会两个添加事务同时执行或同时回退。
- user.setUser_id(1);
- user.setUser_name("tufu");
- user.setUser_password("tufu");
- Grade grade = new Grade();
- grade.setGrade(100);
- grade.setUser(user);
- ms.addGrade(user,grade);
- }
- }
注:将log4j.properties中的log4j日志设置为DEBUG级别,可以看到详细的JTA事务执行情况:
.......
log4j.rootLogger=DEBUG,R,A1
.......
来源:oschina
链接:https://my.oschina.net/u/57229/blog/5525