使用jotm实现跨数据库事务控制

测试环境：mysql-5.5.14，Oracle 10g Express，ow2-jotm-dist-2.1.9，JDK7，Win7

1，背景说明：两个数据库中分别有一张用户表，表结构设计类似，如下：

MySQL中：

CREATE TABLE TUSER
(
  id INT,
  name  VARCHAR(10) NOT NULL,
  PRIMARY KEY (id)
)

 Oracle中:

create table TUSER
(
  id    int primary key,
  name  VARCHAR2(10 CHAR) not null
)

 系统要求同时保存用户信息到这两个数据库中的用户表中。

2,新建Java Project，将两个数据库的驱动以及jotm中lib目录下的相关jar文件加入buildpath中

3，编写实体类

package com.tanlan.jta.entity;
public class User {
	private int id;
	private String name;
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
}

4，编写DAO

package com.tanlan.jta.dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import com.tanlan.jta.entity.User;
public class UserDAO {
	/**
	 * 增加用户信息到MySQL数据库中
	 * 
	 * @param user
	 * @param connection
	 * @throws SQLException
	 */
	public void addUserToMySQL(User user, Connection connection)
			throws SQLException {
		String sql = "insert into TUser values(?,?)";
		PreparedStatement pstmt = connection.prepareStatement(sql);
		pstmt.setInt(1, user.getId());
		pstmt.setString(2, user.getName());
		pstmt.execute();
	}

	/**
	 * 增加用户信息到Oracle数据库中
	 * 
	 * @param user
	 * @param connection
	 * @throws SQLException
	 */
	public void addUserToOracle(User user, Connection connection)
			throws SQLException {
		String sql = "insert into TUser values(?,?)";
		PreparedStatement pstmt = connection.prepareStatement(sql);
		pstmt.setInt(1, user.getId());
		pstmt.setString(2, user.getName());
		pstmt.execute();
	}
}

 

5，编写帮助类，实现启动与停止事务管理服务，以及取得数据库连接：

package com.tanlan.jta.dao;
import java.sql.Connection;
import javax.naming.NamingException;
import javax.sql.XAConnection;
import javax.transaction.UserTransaction;
import org.enhydra.jdbc.standard.StandardXADataSource;
import org.objectweb.jotm.Jotm;
import org.objectweb.transaction.jta.TMService;
public class JotmHelper {
	private TMService jotm;
	private UserTransaction userTransaction;
	/**
	 * 启动事务管理服务
	 */
	public void startTMService() {
		try {
			jotm = new Jotm(true, false);
			userTransaction = jotm.getUserTransaction();
		} catch (NamingException e1) {
			e1.printStackTrace();
		}
	}

	/**
	 * 取得数据库连接
	 * 
	 * @param db
	 * @return
	 * @throws Exception
	 */
	public Connection getConnection(String db) throws Exception {
		StandardXADataSource xads = new StandardXADataSource();
		XAConnection xaconn = null;
		if ("mysql".equals(db)) {
			xads.setDriverName("com.mysql.jdbc.Driver");
			xads.setUrl("jdbc:mysql://localhost/test");
			xads.setTransactionManager(jotm.getTransactionManager());
			xaconn = xads.getXAConnection("root", "root");
		} else if ("oracle".equals(db)) {
			xads.setDriverName("oracle.jdbc.driver.OracleDriver");
			xads.setUrl("jdbc:oracle:thin:@localhost:1521:XE");
			xads.setTransactionManager(jotm.getTransactionManager());
			xaconn = xads.getXAConnection("tanlan", "tanlan");
		} else {

		}
		return xaconn.getConnection();
	}
	public void begin() {
		try {
			userTransaction.begin();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	public void commit() {
		try {
			userTransaction.commit();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	public void rollback() {
		try {
			userTransaction.rollback();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	/**
	 * 停止事务管理服务
	 */
	public void stopTMService() {
		jotm.stop();
		jotm = null;
	}
}

 6，测试代码

package com.tanlan.jta.test;
import java.sql.Connection;
import com.tanlan.jta.dao.JotmHelper;
import com.tanlan.jta.dao.UserDAO;
import com.tanlan.jta.entity.User;
public class TestUSer {
	public static void main(String[] args) {
		User user=new User();
		user.setId(300);
		user.setName("a122456");
		UserDAO dao = new UserDAO();
		JotmHelper helper = new JotmHelper();
		try {
			helper.startTMService();
			Connection mysqlConn = helper.getConnection("mysql");
			Connection oracleConn = helper.getConnection("oracle");
			helper.begin();
			dao.addUserToMySQL(user, mysqlConn);
			dao.addUserToOracle(user, oracleConn);
			helper.commit();
		} catch (Exception e) {
			helper.rollback();
			e.printStackTrace();
		} finally {
			helper.stopTMService();
		}
	}
}

 经过测试，这种方法能够较好的控制对两个数据库操作数据的事务。

评论

1 楼 heipacker 2014-03-31  

确定测试过？