java基于atomikos做分布式事务（简单实例）

做分布式系统时，我们经常会遇到不同资源管理器之间做事务同步的需求。最近手头的项目要求，数据从上游过来时要同步插入到消息中心和Oracle数据库中，这个是很典型的分布式事务场景。JTA是java给出分布式事务的通用解决方案。JTA介绍，这是一篇介绍JTA的很形象的一篇文章。

Atomikos TransactionsEssentials 是一个为Java平台提供增值服务的并且开源的事务管理器。

实例：

jar包依赖

<dependencies><dependency><groupId>com.oracle</groupId><artifactId>ojdbc</artifactId><version>6</version></dependency><dependency><groupId>com.atomikos</groupId><artifactId>transactions-jdbc</artifactId><version>3.7.0</version></dependency><dependency><groupId>com.atomikos</groupId><artifactId>transactions-api</artifactId><version>3.7.0</version></dependency><dependency><groupId>com.atomikos</groupId><artifactId>transactions-jta</artifactId><version>3.7.0</version></dependency><dependency><groupId>com.atomikos</groupId><artifactId>atomikos-util</artifactId><version>3.7.0</version></dependency><dependency><groupId>com.atomikos</groupId><artifactId>transactions</artifactId><version>3.7.0</version></dependency><dependency><groupId>com.atomikos</groupId><artifactId>transactions-jms</artifactId><version>3.7.0</version></dependency></dependencies>

测试类

package com.maple.test;import java.sql.Connection;import java.sql.SQLException;import java.sql.Statement;import javax.transaction.HeuristicMixedException;import javax.transaction.HeuristicRollbackException;import javax.transaction.RollbackException;import javax.transaction.SystemException;import oracle.jdbc.xa.client.OracleXADataSource;import com.atomikos.jdbc.AtomikosDataSourceBean;public class Test {public static void main(String[] args) throws SQLException,IllegalStateException, SecurityException, RollbackException,HeuristicMixedException, HeuristicRollbackException,SystemException {com.atomikos.icatch.jta.UserTransactionImp utx = new com.atomikos.icatch.jta.UserTransactionImp();// 两个数据源,同一实例下建了两个不同的用户// 使用AtomikosDataSourceBean这个类，会自动把数据源资源注册到事务管理器上AtomikosDataSourceBean ds1 = new AtomikosDataSourceBean();OracleXADataSource oxds1 = new OracleXADataSource();oxds1.setURL("jdbc:oracle:thin:@(description=(address=(host=192.168.83.92)(protocol=tcp)(port=1521))(CONNECT_DATA =(SERVER = DEDICATED)(SERVICE_NAME = orcl)))");oxds1.setUser("test1");oxds1.setPassword("test1");ds1.setUniqueResourceName("OracleTest1");ds1.setXaDataSource(oxds1);AtomikosDataSourceBean ds2 = new AtomikosDataSourceBean();OracleXADataSource oxds2 = new OracleXADataSource();oxds2.setURL("jdbc:oracle:thin:@(description=(address=(host=192.168.83.92)(protocol=tcp)(port=1521))(CONNECT_DATA =(SERVER = DEDICATED)(SERVICE_NAME = orcl)))");oxds2.setUser("test2");oxds2.setPassword("test2");ds2.setUniqueResourceName("OracleTest2");ds2.setXaDataSource(oxds2);boolean rollback = false;try {// 开启事务utx.begin();Connection conn2 = ds2.getConnection();Statement stmta2 = conn2.createStatement();stmta2.execute("update INDEXINFO t set index_mode = 4 where t.index_id = 20501");Connection conn1 = ds1.getConnection();Statement stmta1 = conn1.createStatement();stmta1.execute("update INDEXINFO t set index_mode = 4 where t.index_id = 20501");stmta2.close();// AtomikosDataSourceBean维护了连接池，连接关闭为了复用conn2.close();stmta1.close();conn1.close();} catch (Exception e) {e.printStackTrace();rollback = true;} finally {if (!rollback)// 提交事务utx.commit();elseutx.rollback();}}}

例子很简单，不过通过代码的测试可以体会下分布式事务。