Spring Transaction时序图

commit(TransactionStatus)

getTransaction()

ReflectiveMethodInvocation

Commit如果是nested，有savepoint的 releaseHeldSavePoint()如果是新的Transaction，做doCommit（）如果不是新的Transaction，则不做commit，而交由已存在的Transaction提交Rollback如果是nested，做嵌套事务回滚处理如果是新的Transaction，做doRollback()如果没有新建的Transaction，则由线程中前一个Transaction来处理回滚

invokeWithinTransaction()

TransactionAspectSupport

JdkDynamicAopProxy

TransactionSynchronizationManager.unbindResource(obtainDataSource())

isExistingTransaction()

补充：font color=\"#ff9999\

Connection con = txObject.getConnectionHolder().getConnection()connection.commit()

prepareTransactionInfo()

如果存在Transaction：1.PROPAGATION_NEVER -> throw Exception()2.PROPAGATION_NOT_SUPPORTEDsuspend(transaction)挂起当前事务，对当前事务创建SuspendedResourcesHolder，保存当前事务信息，并使用新的数据库连接，且新的数据库连接不在事务里。3.PROPAGATION_REQUIRES_NEWsuspend(transaction)挂起当前事务，对当前事务创建SuspendedResourcesHolder，保存当前事务信息调用doBegin()，设置数据库连接和事务属性，且font color=\"#ff6666\

suspend(transaction)

TransactionAttributeSource.getTransactionAttribute()

doSuspend(transaction)

DataSourceTransactionManager

doCommit(TransactionStatus)

ConnectionHolder = TransactionSynchronizationManager.getResource(obtainDataSource())

methodIdentification

con.setAutoCommit(false)stmt.executeUpdate(\"SET TRANSACTION READ ONLY\")

如果不存在Transaction：1.PROPAGATION_MANDATORY -> throw Exception()2.font color=\"#cc0000\

interceptor.invoke(this)

doBegin1. 首先查看transaction里面是是不是有Connection，没有的话就拿到DataSource创建一个Connection，放到transaction里的ConnectionHolder里面。2. 设置connection一些属性，比如关闭自动提交，以及事务3. TransactionSynchronizationManager.bindResource()关联DataSource和connectionHolder

doGetTransaction

invocation.proceedWithInvocation()

prepareSynchronization()

invocation.proceed()

TransactionInterceptor

DataSourceTransactionManager=determineTransactionManager(txAttribute)

dosuspend会将原来的transaction相关联的Connection释放，并和transaction的信息放在SuspendedResourceHolder里面。重置线程中相关threadLocal变量TransactionSynchronizationManager.setCurrentTransactionName(null)TransactionSynchronizationManager.setCurrentTransactionReadOnly(false);TransactionSynchronizationManager.setCurrentTransactionIsolationLevel(null);TransactionSynchronizationManager.setActualTransactionActive(false);

入口：EnableTransactionManagement -> TransactionManagementConfigurationSelector -> AutoProxyRegistrar -> 注册BeanDefinition internalAutoProxyCreator(InfrastructureAdvisorAutoProxyCreator)-> ProxyTransactionManagementConfiguration -> TransactionInterceptor

txObject.setConnectionHolder(null)

doBegin()

主要拿到transactionManager以及被切的方法

AbstractPlatformTransactionManager

invokeWithinTransaction

processCommit()

doGetTransaction()

invoke()

newTransactionStatus()

this.advised.getInterceptorsAndDynamicInterceptionAdvice

commitTransactionAfterReturning

TransactionInfo = createTransactionIfNecessary

new DataSourceTransactionObject()

invoke（）

这里ConnectionHolder一开始是Null，第一次肯定是新的Transaction

TransactionStatus = tm.getTransaction(txAttr)

handleExistingTransaction