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    mysql的引擎常用的有两个，一个MyISAM，另一个是InnoDB，mysql默认的为MyISAM,而InnoDB才是支持事务的。所以一般需要修改下，如何修改就不说了。

   事务需要依赖数据库，好久没使用声明式事务，今天试了下。关键配置如下。

<tx:advice id="transactionAdvice" transaction-manager="transactionManager">
		<tx:attributes>
			<tx:method name="add*" propagation="REQUIRED" />
			<tx:method name="append*" propagation="REQUIRED" />
			<tx:method name="insert*" propagation="REQUIRED" />
			<tx:method name="save*" propagation="REQUIRED" />
			<tx:method name="update*" propagation="REQUIRED" />
			<tx:method name="modify*" propagation="REQUIRED" />
			<tx:method name="edit*" propagation="REQUIRED" />
			<tx:method name="delete*" propagation="REQUIRED" />
			<tx:method name="remove*" propagation="REQUIRED" />
			<tx:method name="tx*" propagation="REQUIRED" />
			<tx:method name="repair" propagation="REQUIRED" />
			<tx:method name="delAndRepair" propagation="REQUIRED"   />

			<tx:method name="get*" propagation="SUPPORTS" />
			<tx:method name="find*" propagation="SUPPORTS" />
			<tx:method name="load*" propagation="SUPPORTS" />
			<tx:method name="search*" propagation="SUPPORTS" />
			<tx:method name="datagrid*" propagation="SUPPORTS" />

			<tx:method name="*" propagation="SUPPORTS" />
		</tx:attributes>
	</tx:advice>
	<aop:config>
		<aop:pointcut id="transactionPointcut" expression="execution(* com.wondersgroup.employeeBenefits.*.*.service..*Impl.*(..))" />
		
		<!-- com.wondersgroup.benefit.*.core.service..*Impl.*(..) -->
		<aop:advisor pointcut-ref="transactionPointcut" advice-ref="transactionAdvice" />
	</aop:config>

　　事务配置好之后再service中手动抛了个exception，结果没有回滚，service方法如下

 @Override
    public int saveBudgetApplyInfo(BudgetApplyInfo budgetApplyInfo) throws Exception {
         budgetApplyInfoMapper.insert(budgetApplyInfo);
        if(1==1){

            throw new Exception();
        }
        return 1;
    }

　　跟着断点一步步进去查看原因

在

TransactionAspectSupport中发现这样一个方法

/**
	 * Handle a throwable, completing the transaction.
	 * We may commit or roll back, depending on the configuration.
	 * @param txInfo information about the current transaction
	 * @param ex throwable encountered
	 */
	protected void completeTransactionAfterThrowing(TransactionInfo txInfo, Throwable ex) {
		if (txInfo != null && txInfo.hasTransaction()) {
			if (logger.isTraceEnabled()) {
				logger.trace("Completing transaction for [" + txInfo.getJoinpointIdentification() +
						"] after exception: " + ex);
			}
			if (txInfo.transactionAttribute.rollbackOn(ex)) {
				try {
					txInfo.getTransactionManager().rollback(txInfo.getTransactionStatus());
				}
				catch (TransactionSystemException ex2) {
					logger.error("Application exception overridden by rollback exception", ex);
					ex2.initApplicationException(ex);
					throw ex2;
				}
				catch (RuntimeException ex2) {
					logger.error("Application exception overridden by rollback exception", ex);
					throw ex2;
				}
				catch (Error err) {
					logger.error("Application exception overridden by rollback error", ex);
					throw err;
				}
			}
			else {
				// We don't roll back on this exception.
				// Will still roll back if TransactionStatus.isRollbackOnly() is true.
				try {
					txInfo.getTransactionManager().commit(txInfo.getTransactionStatus());
				}
				catch (TransactionSystemException ex2) {
					logger.error("Application exception overridden by commit exception", ex);
					ex2.initApplicationException(ex);
					throw ex2;
				}
				catch (RuntimeException ex2) {
					logger.error("Application exception overridden by commit exception", ex);
					throw ex2;
				}
				catch (Error err) {
					logger.error("Application exception overridden by commit error", ex);
					throw err;
				}
			}
		}
	}

　　上面的方法中有这么一段

txInfo.transactionAttribute.rollbackOn(ex)，这里是判断是否需要执行回滚操作的，跟踪rollbackOn方法最后会执行到

DefaultTransactionAttribute中的rollbackOn方法

/**
	 * The default behavior is as with EJB: rollback on unchecked exception.
	 * Additionally attempt to rollback on Error.
	 * <p>This is consistent with TransactionTemplate's default behavior.
	 */
	public boolean rollbackOn(Throwable ex) {
		return (ex instanceof RuntimeException || ex instanceof Error);
	}

　　看到这里，应该都清楚了。。。自己主动抛异常Exception是不对的。这里只捕获运行时异常

RuntimeException 及Error，所以我们测试时不可以直接抛Exception，而应该换成

RuntimeException 。当然。也可在xml中指定rollback-for

<tx:method name="add*" propagation="REQUIRED" rollback-for="Exception" />

　　最后：个人还是比较喜欢基于注解的事务处理