spring事务管理PlatformTransactionManager及transactionTemplate

事务三大接口

  org.springframework.transaction.PlatformTransactionManager 事务管理器
  org.springframework.transaction.TransactionDefinition 事务的一些基础信息，如超时时间、隔离级别、传播属性等
  org.springframework.transaction.TransactionStatus 事务的一些状态信息，如是否一个新的事务、是否已被标记为回滚

PlatformTransactionManager

public interface PlatformTransactionManager {
    //根据事务定义TransactionDefinition，获取事务
    TransactionStatus getTransaction(TransactionDefinition definition);
    //提交事务
    void commit(TransactionStatus status);
    //回滚事务
    void rollback(TransactionStatus status);
}

事务定义接口TransactionDefinition

// 事务的定义包括: 事务的隔离级别，事务的传播属性，超时时间设置
// ，是否只读事务的隔离级别是数据库本身的事务功能，事务的播属性则是spring为我们提供的功能
 该接口的实现DefaultTransactionDefinition,默认的事务定义

public class DefaultTransactionDefinition implements TransactionDefinition, Serializable {
	//事务的传播属性默认为PROPAGATION_REQUIRED，即当前没有事务的时候，创建一个，如果有则使用当前事务
   private int propagationBehavior = PROPAGATION_REQUIRED;
   //事务的隔离级别采用底层数据库默认的隔离级别
   private int isolationLevel = ISOLATION_DEFAULT;
   //超时时间采用底层数据库默认的超时时间
   private int timeout = TIMEOUT_DEFAULT;
   //是否只读为false
   private boolean readOnly = false;
   ...
} 

事务接口定义 TransactionStatus

TransactionStatus它继承了SavepointManager接口，SavepointManager是对事务中上述保存点功能的封装

public interface SavepointManager {
    Object createSavepoint() throws TransactionException;
    void rollbackToSavepoint(Object savepoint) throws TransactionException;
    void releaseSavepoint(Object savepoint) throws TransactionException;
}

TransactionStatus本身更多存储的是事务的一些状态信息 是否是一个新的事物 是否有保存点 是否已被标记为回滚

PlatformTransactionManager+transactionStatus使用demo

执行demo

@Autowired
private PlatformTransactionManager transactionManager;

TransactionStatus status = null;
// 手动开启事务
status = transactionManager.getTransaction(new DefaultTransactionDefinition());

// 事务提交
transactionManager.commit(status);

// 事务回滚
if (StringMoreUtils.checkValNotNull(status)) {
    transactionManager.rollback(status);
}

demo2

@Autowired
private PlatformTransactionManager platformTransactionManager;
@Autowired
private TransactionDefinition transactionDefinition;

//开始事务
TransactionStatus transactionStatus = platformTransactionManager.getTransaction(transactionDefinition);
try {
    orderInfoList.forEach(el -> {
        orderInfoDao.updateShopSimpleName(el.getShopSimpleName(), el.getId().toString());
    });
    //commit
    platformTransactionManager.commit(transactionStatus);
} catch (TransactionException e) {
    e.printStackTrace();
    //rollback
    platformTransactionManager.rollback(transactionStatus);
}

transactionTemplate使用demo

private PayOrderDAO payOrderDAO;  

protected TransactionTemplate transactionTemplate;  

/** 

- 保存支付订单 
  */  
  protected PayOrder savePayReq(final PayOrder payOrder) {  

  @Autowired
  private TransactionTemplate transactionTemplate;

   @Autowired
  private PayOrderDAO payOrderDAO;

  PayOrder order = (PayOrder) this.transactionTemplate  
          .execute(new TransactionCallback() {  
              @Override  
              public Object doInTransaction(TransactionStatus status) {  
                  // 查看是否已经存在支付订单，如果已经存在则返回订单主键  
                  PayOrder payOrderTemp = payOrderDAO.findOrder(String  
                          .valueOf(payOrder.getPayOrderId()));  
              // 由支付渠道类型(PayChannelType)转换得到交易类型(PayType)  
              if (payOrder.getPayChannelId().equalsIgnoreCase(PAY_CHNL_ACT_BAL)) {// 账户余额支付  
                  payOrder.setPayType("3");  
              } else if (payOrder.getPayChannelId().equalsIgnoreCase(PAY_CHNL_FAST_PAY)) {// 联通快捷支付  
                  payOrder.setPayType("4");  
              } else {// 网银网关支付  
                  payOrder.setPayType("2");  
              }  
  
              // 比对新的支付金额与原订单金额是否一致，如不一致则提示错误  
              if (payOrderTemp == null) {  
                  String orderId = payOrderDAO.save(payOrder);  
                  payOrder.setPayOrderId(orderId);  
                  return payOrder;  
              } else {  
                  return payOrderTemp;  
              }  
          }  
      });
  if ("2".equals(order.getOrderState())) {// 2：表示支付成功  
      throw new EpaymentBizException(StatusCode.DQSystem.PAY_FAIL,  
              "同一订单不能重复支付");  
  } else if (payOrder.getPayAmt().longValue() != order.getPayAmt()  
          .longValue()) {  
      throw new EpaymentBizException(StatusCode.DQSystem.PAY_FAIL,  
              "交易金额与原订单不一致");  
  } else {  
      return payOrder;  
  }  

}

参考了大佬的博文
https://juejin.cn/post/6844904086341419021