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mysql-XA协议的分布式事务

2021-07-13 11:35  Tony、  阅读(207)  评论(0编辑  收藏  举报
public static void main(String[] args) throws SQLException {
        //true表示打印XA语句,,用于调试
        boolean logXaCommands = true;
        // 获得资源管理器操作接口实例 RM1
        Connection conn1 = DriverManager.getConnection("jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useUnicode=true&characterEncoding=utf8&characterSetResults=utf8", "root", "123456");
        XAConnection xaConn1 = new MysqlXAConnection((com.mysql.cj.jdbc.ConnectionImpl)conn1, logXaCommands);
        XAResource rm1 = xaConn1.getXAResource();

        // 获得资源管理器操作接口实例 RM2
        Connection conn2 = DriverManager.getConnection("jdbc:mysql://localhost:3306/test?serverTimezone=UTC&useUnicode=true&characterEncoding=utf8&characterSetResults=utf8", "root", "123456");
        XAConnection xaConn2 = new MysqlXAConnection((com.mysql.cj.jdbc.ConnectionImpl)conn2, logXaCommands);
        XAResource rm2 = xaConn2.getXAResource();
        // AP请求TM执行一个分布式事务,TM生成全局事务id
        byte[] gtrid = "g12345".getBytes();
        int formatId = 1;
        try {
            // ==============分别执行RM1和RM2上的事务分支====================
            // TM生成rm1上的事务分支id
            byte[] bqual1 = "b00001".getBytes();
            Xid xid1 = new MysqlXid(gtrid, bqual1, formatId);
            // 执行rm1上的事务分支 One of TMNOFLAGS, TMJOIN, or TMRESUME.
            rm1.start(xid1, XAResource.TMNOFLAGS);
            // 业务1:插入user表
            PreparedStatement ps1 = conn1.prepareStatement("INSERT into a VALUES (99, 99)");
            ps1.execute();
            rm1.end(xid1, XAResource.TMSUCCESS);

            // TM生成rm2上的事务分支id
            byte[] bqual2 = "b00002".getBytes();
            Xid xid2 = new MysqlXid(gtrid, bqual2, formatId);
            // 执行rm2上的事务分支
            rm2.start(xid2, XAResource.TMNOFLAGS);
            // 业务2:插入user_msg表
            PreparedStatement ps2 = conn2.prepareStatement("INSERT into b VALUES (88, 99)");
            ps2.execute();
            rm2.end(xid2, XAResource.TMSUCCESS);

            // ===================两阶段提交================================
            // phase1:询问所有的RM 准备提交事务分支
            int rm1Prepare = rm1.prepare(xid1);
            int rm2Prepare = rm2.prepare(xid2);
            // phase2:提交所有事务分支
            boolean onePhase = false;
            //TM判断有2个事务分支,所以不能优化为一阶段提交
            if (rm1Prepare == XAResource.XA_OK
                    && rm2Prepare == XAResource.XA_OK
            ) {
                //所有事务分支都prepare成功,提交所有事务分支
                rm1.commit(xid1, onePhase);
                rm2.commit(xid2, onePhase);
            } else {
                //如果有事务分支没有成功,则回滚
                rm1.rollback(xid1);
                rm1.rollback(xid2);
            }
        } catch (XAException e) {
            // 如果出现异常,也要进行回滚
            e.printStackTrace();
        }
    }

 

参考:

https://www.cnblogs.com/dennyzhangdd/p/10975192.html

http://www.tianshouzhi.com/api/tutorials/distributed_transaction/384