javaweb分布式事务
分布式事务是指操作多个数据库之间的事务,spring的 org.springframework.transaction.jta.JtaTransactionManager,提供了分布式事务支持。如果使 用WAS的JTA支持,把它的属性改为WebSphere对应的TransactionManager。
在tomcat下,是没有分布式事务的,不过可以借助于第三方软件jotm(Java Open Transaction
Manager
)和AtomikosTransactionsEssentials实现,在spring中分布式事务是通过jta(jotm,atomikos)来进行
实现。
1、http://jotm.objectweb.org/
2、http://www.atomikos.com/Main/TransactionsEssentials
一、使用JOTM例子
(1)、Dao及实现
- public interface GenericDao {
- public int save(String ds, String sql, Object[] obj) throws Exception;
- public int findRowCount(String ds, String sql);
- }
- public class GenericDaoImpl implements GenericDao{
- private JdbcTemplate jdbcTemplateA;
- private JdbcTemplate jdbcTemplateB;
- public void setJdbcTemplateA(JdbcTemplate jdbcTemplate) {
- this.jdbcTemplateA = jdbcTemplate;
- }
- public void setJdbcTemplateB(JdbcTemplate jdbcTemplate) {
- this.jdbcTemplateB = jdbcTemplate;
- }
- public int save(String ds, String sql, Object[] obj) throws Exception{
- if(null == ds || "".equals(ds)) return -1;
- try{
- if(ds.equals("A")){
- return this.jdbcTemplateA.update(sql, obj);
- }else{
- return this.jdbcTemplateB.update(sql, obj);
- }
- }catch(Exception e){
- e.printStackTrace();
- throw new Exception("执行" + ds + "数据库时失败!");
- }
- }
- public int findRowCount(String ds, String sql) {
- if(null == ds || "".equals(ds)) return -1;
- if(ds.equals("A")){
- return this.jdbcTemplateA.queryForInt(sql);
- }else{
- return this.jdbcTemplateB.queryForInt(sql);
- }
- }
- }
(2)、Service及实现
- public interface UserService {
- public void saveUser() throws Exception;
- }
- public class UserServiceImpl implements UserService{
- private GenericDao genericDao;
- public void setGenericDao(GenericDao genericDao) {
- this.genericDao = genericDao;
- }
- public void saveUser() throws Exception {
- String userName = "user_" + Math.round(Math.random()*10000);
- System.out.println(userName);
- StringBuilder sql = new StringBuilder();
- sql.append(" insert into t_user(username, gender) values(?,?); ");
- Object[] objs = new Object[]{userName,"1"};
- genericDao.save("A", sql.toString(), objs);
- sql.delete(0, sql.length());
- sql.append(" insert into t_user(name, sex) values(?,?); ");
- objs = new Object[]{userName,"男的"};//值超出范围
- genericDao.save("B", sql.toString(), objs);
- }
- }
(3)、applicationContext-jotm.xml
- <?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:context="http://www.springframework.org/schema/context"
- xmlns:aop="http://www.springframework.org/schema/aop"
- xmlns:tx="http://www.springframework.org/schema/tx"
- xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
- http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd
- http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
- http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd">
- <description>springJTA</description>
- <!--指定Spring配置中用到的属性文件-->
- <bean id="propertyConfig"
- class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
- <property name="locations">
- <list>
- <value>classpath:jdbc.properties</value>
- </list>
- </property>
- </bean>
- <!-- JOTM实例 -->
- <bean id="jotm" class="org.springframework.transaction.jta.JotmFactoryBean">
- <property name="defaultTimeout" value="500000"/>
- </bean>
- <!-- JTA事务管理器 -->
- <bean id="jtaTransactionManager" class="org.springframework.transaction.jta.JtaTransactionManager">
- <property name="userTransaction" ref="jotm" />
- </bean>
- <!-- 数据源A -->
- <bean id="dataSourceA" class="org.enhydra.jdbc.pool.StandardXAPoolDataSource" destroy-method="shutdown">
- <property name="dataSource">
- <bean class="org.enhydra.jdbc.standard.StandardXADataSource" destroy-method="shutdown">
- <property name="transactionManager" ref="jotm"/>
- <property name="driverName" value="${jdbc.driver}"/>
- <property name="url" value="${jdbc.url}"/>
- </bean>
- </property>
- <property name="user" value="${jdbc.username}"/>
- <property name="password" value="${jdbc.password}"/>
- </bean>
- <!-- 数据源B -->
- <bean id="dataSourceB" class="org.enhydra.jdbc.pool.StandardXAPoolDataSource" destroy-method="shutdown">
- <property name="dataSource">
- <bean class="org.enhydra.jdbc.standard.StandardXADataSource" destroy-method="shutdown">
- <property name="transactionManager" ref="jotm"/>
- <property name="driverName" value="${jdbc2.driver}"/>
- <property name="url" value="${jdbc2.url}"/>
- </bean>
- </property>
- <property name="user" value="${jdbc2.username}"/>
- <property name="password" value="${jdbc2.password}"/>
- </bean>
- <bean id = "jdbcTemplateA"
- class = "org.springframework.jdbc.core.JdbcTemplate">
- <property name = "dataSource" ref="dataSourceA"/>
- </bean>
- <bean id = "jdbcTemplateB"
- class = "org.springframework.jdbc.core.JdbcTemplate">
- <property name = "dataSource" ref="dataSourceB"/>
- </bean>
- <!-- 事务切面配置 -->
- <aop:config>
- <aop:pointcut id="pointCut"
- expression="execution(* com.logcd.service..*.*(..))"/><!-- 包及其子包下的所有方法 -->
- <aop:advisor pointcut-ref="pointCut" advice-ref="txAdvice"/>
- <aop:advisor pointcut="execution(* *..common.service..*.*(..))" advice-ref="txAdvice"/>
- </aop:config>
- <!-- 通知配置 -->
- <tx:advice id="txAdvice" transaction-manager="jtaTransactionManager">
- <tx:attributes>
- <tx:method name="delete*" rollback-for="Exception"/>
- <tx:method name="save*" rollback-for="Exception"/>
- <tx:method name="update*" rollback-for="Exception"/>
- <tx:method name="find*" read-only="true" rollback-for="Exception"/>
- </tx:attributes>
- </tx:advice>
- <bean id="genericDao"
- class="com.logcd.dao.impl.GenericDaoImpl" autowire="byName">
- </bean>
- <bean id="userService"
- class="com.logcd.service.impl.UserServiceImpl" autowire="byName">
- </bean>
- </beans>
(4)、测试
- public class TestUserService{
- private static UserService userService;
- @BeforeClass
- public static void init(){
- ApplicationContext app = new ClassPathXmlApplicationContext("applicationContext-jotm.xml");
- userService = (UserService)app.getBean("userService");
- }
- @Test
- public void save(){
- System.out.println("begin...");
- try{
- userService.saveUser();
- }catch(Exception e){
- System.out.println(e.getMessage());
- }
- System.out.println("finish...");
- }
- }
二、关于使用atomikos实现
(1)、数据源配置
- <bean id="dataSourceA" class="com.atomikos.jdbc.SimpleDataSourceBean" init-method="init" destroy-method="close">
- <property name="uniqueResourceName">
- <value>${datasource.uniqueResourceName}</value>
- </property>
- <property name="xaDataSourceClassName">
- <value>${database.driver_class}</value>
- </property>
- <property name="xaDataSourceProperties">
- <value>URL=${database.url};user=${database.username};password=${database.password}</value>
- </property>
- <property name="exclusiveConnectionMode">
- <value>${connection.exclusive.mode}</value>
- </property>
- <property name="connectionPoolSize">
- <value>${connection.pool.size}</value>
- </property>
- <property name="connectionTimeout">
- <value>${connection.timeout}</value>
- </property>
- <property name="validatingQuery">
- <value>SELECT 1</value>
- </property>
- </bean>
(2)、事务配置
- <bean id="atomikosTransactionManager" class="com.atomikos.icatch.jta.UserTransactionManager"
- init-method="init" destroy-method="close">
- <property name="forceShutdown" value="true"/>
- </bean>
- <bean id="atomikosUserTransaction" class="com.atomikos.icatch.jta.UserTransactionImp">
- <property name="transactionTimeout" value="${transaction.timeout}"/>
- </bean>
- <!-- JTA事务管理器 -->
- <bean id="springTransactionManager" class="org.springframework.transaction.jta.JtaTransactionManager">
- <property name="transactionManager" ref="atomikosTransactionManager"/>
- <property name="userTransaction" ref="atomikosUserTransaction"/>
- </bean>
- <!-- 事务切面配置 -->
- <aop:config>
- <aop:pointcut id="serviceOperation" expression="execution(* *..service*..*(..))"/>
- <aop:advisor pointcut-ref="serviceOperation" advice-ref="txAdvice"/>
- </aop:config>
- <!-- 通知配置 -->
- <tx:advice id="txAdvice" transaction-manager="springTransactionManager">
- <tx:attributes>
- <tx:method name="*" rollback-for="Exception"/>
- </tx:attributes>
- </tx:advice>
- lib.rar (5.2 MB)
- 描述: JOTM使用包
- 转自:http://log-cd.iteye.com/blog/807607