事务执行过程
注解式声明事务通过ProxyTransactionManagementConfiguration配置了事务拦截器
@Bean
@Role(BeanDefinition.ROLE_INFRASTRUCTURE)
public TransactionInterceptor transactionInterceptor(TransactionAttributeSource transactionAttributeSource) {
TransactionInterceptor interceptor = new TransactionInterceptor();
interceptor.setTransactionAttributeSource(transactionAttributeSource);
if (this.txManager != null) {
interceptor.setTransactionManager(this.txManager);
}
return interceptor;
}
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# 事务拦截方法
TransactionInterceptor.invoke
public Object invoke(MethodInvocation invocation) throws Throwable {
// 当前类可能是代理类，获取当前类的真实类型
Class<?> targetClass = (invocation.getThis() != null ? AopUtils.getTargetClass(invocation.getThis()) : null);
// 执行拦截方法，这里将控制通知方法执行的proceed方法作为函数传入
return invokeWithinTransaction(invocation.getMethod(), targetClass, invocation::proceed);
}
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调用父类方法
TransactionAspectSupport#invokeWithinTransaction
protected Object invokeWithinTransaction(Method method, @Nullable Class<?> targetClass,
final InvocationCallback invocation) throws Throwable {
TransactionAttributeSource tas = getTransactionAttributeSource();
//获取@Transactional注解配置
final TransactionAttribute txAttr = (tas != null ? tas.getTransactionAttribute(method, targetClass) : null);
//获取注解指明的事务管理器，注解未指明则使用默认的
final TransactionManager tm = determineTransactionManager(txAttr);
//响应式编程暂未接触，略过响应式事务。。。
PlatformTransactionManager ptm = asPlatformTransactionManager(tm);
//生成切入点标识字符串
final String joinpointIdentification = methodIdentification(method, targetClass, txAttr);
if (txAttr == null || !(ptm instanceof CallbackPreferringPlatformTransactionManager)) {
//创建事务
TransactionInfo txInfo = createTransactionIfNecessary(ptm, txAttr, joinpointIdentification);
Object retVal;
try {
// 将主导权交给通知方法执行器，继续执行其他通知方法，最后执行目标方法
//由于设置了事务通知方法的优先级最小，一般事务通知排在最后，之后就执行目标方法了
retVal = invocation.proceedWithInvocation();
}
catch (Throwable ex) {
// 抛异常，根据条件决定是否回滚
completeTransactionAfterThrowing(txInfo, ex);
throw ex;
}
finally {
cleanupTransactionInfo(txInfo);
}
if (vavrPresent && VavrDelegate.isVavrTry(retVal)) {
// 如果使用了Vavr框架，提供支持Vavr框架的异常回滚
TransactionStatus status = txInfo.getTransactionStatus();
if (status != null && txAttr != null) {
retVal = VavrDelegate.evaluateTryFailure(retVal, txAttr, status);
}
}
//提交事务
commitTransactionAfterReturning(txInfo);
return retVal;
}
else {
//CallbackPreferringPlatformTransactionManager的作用暂未理解，先忽略
}
}
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# 创建事务
以DataSourceTransactionManager为例
TransactionAspectSupport#createTransactionIfNecessary
protected TransactionInfo createTransactionIfNecessary(@Nullable PlatformTransactionManager tm,
@Nullable TransactionAttribute txAttr, final String joinpointIdentification) {
TransactionStatus status = null;
if (txAttr != null) {
if (tm != null) {
//根据配置的事务传播等级，返回当前事务或创建一个事务
status = tm.getTransaction(txAttr);
}
else {
if (logger.isDebugEnabled()) {
logger.debug("Skipping transactional joinpoint [" + joinpointIdentification +
"] because no transaction manager has been configured");
}
}
}
//转成TransactionInfo对象
return prepareTransactionInfo(tm, txAttr, joinpointIdentification, status);
}
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AbstractPlatformTransactionManager#getTransaction
public final TransactionStatus getTransaction(@Nullable TransactionDefinition definition)
throws TransactionException {
// 事务配置为空则提供默认配置 传播级别REQUIRED，隔离等级：数据库默认等级
TransactionDefinition def = (definition != null ? definition : TransactionDefinition.withDefaults());
//获取事务
Object transaction = doGetTransaction();
boolean debugEnabled = logger.isDebugEnabled();
//判断当前线程是否已存在事务
if (isExistingTransaction(transaction)) {
// 处理已存在事务的情况
return handleExistingTransaction(def, transaction, debugEnabled);
}
// 默认超时时间是-1，如果设置，不应该小于该值
if (def.getTimeout() < TransactionDefinition.TIMEOUT_DEFAULT) {
throw new InvalidTimeoutException("Invalid transaction timeout", def.getTimeout());
}
// 事务传播级别设置的是MANDATORY，强制调用方需要有事务
if (def.getPropagationBehavior() == TransactionDefinition.PROPAGATION_MANDATORY) {
throw new IllegalTransactionStateException(
"No existing transaction found for transaction marked with propagation 'mandatory'");
}
//这三种需要新建事务
else if (def.getPropagationBehavior() == TransactionDefinition.PROPAGATION_REQUIRED ||
def.getPropagationBehavior() == TransactionDefinition.PROPAGATION_REQUIRES_NEW ||
def.getPropagationBehavior() == TransactionDefinition.PROPAGATION_NESTED) {
//暂停当前事务，这里没有当前事务，实际上方法内是没有处理的，返回也是null。这里可能只是为了形式统一。
SuspendedResourcesHolder suspendedResources = suspend(null);
try {
//开启事务
return startTransaction(def, transaction, debugEnabled, suspendedResources);
}
catch (RuntimeException | Error ex) {
//恢复之前被挂起的事务
resume(null, suspendedResources);
throw ex;
}
}
else {
// Create "empty" transaction: no actual transaction, but potentially synchronization.
if (def.getIsolationLevel() != TransactionDefinition.ISOLATION_DEFAULT && logger.isWarnEnabled()) {
logger.warn("Custom isolation level specified but no actual transaction initiated; " +
"isolation level will effectively be ignored: " + def);
}
boolean newSynchronization = (getTransactionSynchronization() == SYNCHRONIZATION_ALWAYS);
//设置当前线程无事务
return prepareTransactionStatus(def, null, true, newSynchronization, debugEnabled, null);
}
}
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DataSourceTransactionManager#doGetTransaction
protected Object doGetTransaction() {
DataSourceTransactionObject txObject = new DataSourceTransactionObject();
//设置是否允许嵌套事务，构造时默认是true
txObject.setSavepointAllowed(isNestedTransactionAllowed());
//获取当前线程建立的数据库连接
ConnectionHolder conHolder =
(ConnectionHolder) TransactionSynchronizationManager.getResource(obtainDataSource());
txObject.setConnectionHolder(conHolder, false);
return txObject;
}
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根据是否建立连接来判断是否已存在事务
DataSourceTransactionManager#isExistingTransaction
protected boolean isExistingTransaction(Object transaction) {
DataSourceTransactionObject txObject = (DataSourceTransactionObject) transaction;
return (txObject.hasConnectionHolder() && txObject.getConnectionHolder().isTransactionActive());
}
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# 当前线程无事务
AbstractPlatformTransactionManager#startTransaction
private TransactionStatus startTransaction(TransactionDefinition definition, Object transaction,
boolean debugEnabled, @Nullable SuspendedResourcesHolder suspendedResources) {
//默认值是SYNCHRONIZATION_ALWAYS 需要事务同步
boolean newSynchronization = (getTransactionSynchronization() != SYNCHRONIZATION_NEVER);
//会保存被挂起的事务，当前事务执行完，恢复被挂起事务时会用到
DefaultTransactionStatus status = newTransactionStatus(
definition, transaction, true, newSynchronization, debugEnabled, suspendedResources);
// 开始创建事务
doBegin(transaction, definition);
//初始化线程同步信息
prepareSynchronization(status, definition);
return status;
}
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AbstractPlatformTransactionManager#newTransactionStatus
protected DefaultTransactionStatus newTransactionStatus(
TransactionDefinition definition, @Nullable Object transaction, boolean newTransaction,
boolean newSynchronization, boolean debug, @Nullable Object suspendedResources) {
//需要事务，且事务同步器为空时才创建，防止重复创建
boolean actualNewSynchronization = newSynchronization &&
!TransactionSynchronizationManager.isSynchronizationActive();
return new DefaultTransactionStatus(
transaction, newTransaction, actualNewSynchronization,
definition.isReadOnly(), debug, suspendedResources);
}
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DataSourceTransactionManager#doBegin
protected void doBegin(Object transaction, TransactionDefinition definition) {
DataSourceTransactionObject txObject = (DataSourceTransactionObject) transaction;
Connection con = null;
try {
//没有连接才创建，即没有事务才创建新事务
if (!txObject.hasConnectionHolder() ||
txObject.getConnectionHolder().isSynchronizedWithTransaction()) {
//获取数据库连接
Connection newCon = obtainDataSource().getConnection();
//标记连接是新创建的
txObject.setConnectionHolder(new ConnectionHolder(newCon), true);
}
txObject.getConnectionHolder().setSynchronizedWithTransaction(true);
con = txObject.getConnectionHolder().getConnection();
//设置设置数据库连接的传播级别和隔离等级，如果不使用数据库默认的隔离级别，返回修改之前的隔离级别
Integer previousIsolationLevel = DataSourceUtils.prepareConnectionForTransaction(con, definition);
txObject.setPreviousIsolationLevel(previousIsolationLevel);
txObject.setReadOnly(definition.isReadOnly());
// Switch to manual commit if necessary. This is very expensive in some JDBC drivers,
// so we don't want to do it unnecessarily (for example if we've explicitly
// configured the connection pool to set it already).
if (con.getAutoCommit()) {
txObject.setMustRestoreAutoCommit(true);
if (logger.isDebugEnabled()) {
logger.debug("Switching JDBC Connection [" + con + "] to manual commit");
}
//Spring的注释说不想设置成手动提交，但是这里又设置手动提交。。。有点晕
//猜测是Spring来处理事务提交
con.setAutoCommit(false);
}
//如果是readOnly，设置连接
prepareTransactionalConnection(con, definition);
txObject.getConnectionHolder().setTransactionActive(true);
int timeout = determineTimeout(definition);
if (timeout != TransactionDefinition.TIMEOUT_DEFAULT) {
txObject.getConnectionHolder().setTimeoutInSeconds(timeout);
}
// 如果是新创建的连接，同步当前线程的连接
if (txObject.isNewConnectionHolder()) {
TransactionSynchronizationManager.bindResource(obtainDataSource(), txObject.getConnectionHolder());
}
}
catch (Throwable ex) {
if (txObject.isNewConnectionHolder()) {
//释放新创建的连接
DataSourceUtils.releaseConnection(con, obtainDataSource());
txObject.setConnectionHolder(null, false);
}
throw new CannotCreateTransactionException("Could not open JDBC Connection for transaction", ex);
}
}
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从源码可以看出doBegion方法主要是针对数据库连接，只有在当前没有连接的时候才会创建连接，否则使用原来的连接。
AbstractPlatformTransactionManager#prepareSynchronization
protected void prepareSynchronization(DefaultTransactionStatus status, TransactionDefinition definition) {
//上面提到的AbstractPlatformTransactionManager#newTransactionStatus保证了只会在第一次创建事务的时候才真正为true
if (status.isNewSynchronization()) {
//同步线程当前的事务状态
TransactionSynchronizationManager.setActualTransactionActive(status.hasTransaction());
TransactionSynchronizationManager.setCurrentTransactionIsolationLevel(
definition.getIsolationLevel() != TransactionDefinition.ISOLATION_DEFAULT ?
definition.getIsolationLevel() : null);
TransactionSynchronizationManager.setCurrentTransactionReadOnly(definition.isReadOnly());
TransactionSynchronizationManager.setCurrentTransactionName(definition.getName());
//同步器初始化
TransactionSynchronizationManager.initSynchronization();
}
}
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# 当前线程存在事务
AbstractPlatformTransactionManager#handleExistingTransaction
private TransactionStatus handleExistingTransaction(
TransactionDefinition definition, Object transaction, boolean debugEnabled)
throws TransactionException {
//NEVER 限制目标方法不能有事务，调用方的方法也不能有事务
if (definition.getPropagationBehavior() == TransactionDefinition.PROPAGATION_NEVER) {
throw new IllegalTransactionStateException(
"Existing transaction found for transaction marked with propagation 'never'");
}
//NOT_SUPPORTED 目标方法不支持事务
if (definition.getPropagationBehavior() == TransactionDefinition.PROPAGATION_NOT_SUPPORTED) {
//挂起当前事务
Object suspendedResources = suspend(transaction);
boolean newSynchronization = (getTransactionSynchronization() == SYNCHRONIZATION_ALWAYS);
//同步当前线程的事务信息为无事务
return prepareTransactionStatus(
definition, null, false, newSynchronization, debugEnabled, suspendedResources);
}
//REQUIRES_NEW 目标方法需要创建新事务
if (definition.getPropagationBehavior() == TransactionDefinition.PROPAGATION_REQUIRES_NEW) {
if (debugEnabled) {
logger.debug("Suspending current transaction, creating new transaction with name [" +
definition.getName() + "]");
}
//挂起当前事务
SuspendedResourcesHolder suspendedResources = suspend(transaction);
try {
//创建新事务
return startTransaction(definition, transaction, debugEnabled, suspendedResources);
}
catch (RuntimeException | Error beginEx) {
resumeAfterBeginException(transaction, suspendedResources, beginEx);
throw beginEx;
}
}
// NESTED 嵌套事务
if (definition.getPropagationBehavior() == TransactionDefinition.PROPAGATION_NESTED) {
if (!isNestedTransactionAllowed()) {
//是否允许嵌套事务，DataSourceTransactionManager默认是true，允许嵌套事务
throw new NestedTransactionNotSupportedException(
"Transaction manager does not allow nested transactions by default - " +
"specify 'nestedTransactionAllowed' property with value 'true'");
}
//使用嵌套事务的保存点，DataSourceTransactionManager没有重写该方法，默认是true
if (useSavepointForNestedTransaction()) {
//嵌套事务不会新建事务，而是通过设置保存点来完成提交和回滚
DefaultTransactionStatus status =
prepareTransactionStatus(definition, transaction, false, false, debugEnabled, null);
//保存点计数+1
status.createAndHoldSavepoint();
return status;
}
else {
// JtaTransactionManager重写了useSavepointForNestedTransaction 返回false
// 调用会调用JtaTransactionManager.doBegin方法
return startTransaction(definition, transaction, debugEnabled, null);
}
}
// Assumably PROPAGATION_SUPPORTS or PROPAGATION_REQUIRED.
//还剩下 SUPPORTS、REQUIRED、MANDATORY三种传播级别，都是沿用已存在的事务
// Spring的注释看起来漏说了一种，可以提个issue??哈哈。。。
if (debugEnabled) {
logger.debug("Participating in existing transaction");
}
if (isValidateExistingTransaction()) {
//检查隔离级别和只读属性的设置，要跟已存在的事务设置一致
//默认是不检查的
if (definition.getIsolationLevel() != TransactionDefinition.ISOLATION_DEFAULT) {
Integer currentIsolationLevel = TransactionSynchronizationManager.getCurrentTransactionIsolationLevel();
if (currentIsolationLevel == null || currentIsolationLevel != definition.getIsolationLevel()) {
Constants isoConstants = DefaultTransactionDefinition.constants;
throw new IllegalTransactionStateException("Participating transaction with definition [" +
definition + "] specifies isolation level which is incompatible with existing transaction: " +
(currentIsolationLevel != null ?
isoConstants.toCode(currentIsolationLevel, DefaultTransactionDefinition.PREFIX_ISOLATION) :
"(unknown)"));
}
}
if (!definition.isReadOnly()) {
if (TransactionSynchronizationManager.isCurrentTransactionReadOnly()) {
throw new IllegalTransactionStateException("Participating transaction with definition [" +
definition + "] is not marked as read-only but existing transaction is");
}
}
}
boolean newSynchronization = (getTransactionSynchronization() != SYNCHRONIZATION_NEVER);
return prepareTransactionStatus(definition, transaction, false, newSynchronization, debugEnabled, null);
}
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AbstractPlatformTransactionManager#suspend
protected final SuspendedResourcesHolder suspend(@Nullable Object transaction) throws TransactionException {
//创建事务后在prepareSynchronization方法会初始化同步信息，isSynchronizationActive为true
if (TransactionSynchronizationManager.isSynchronizationActive()) {
//未找到向该list添加元素的地方，先忽略
List<TransactionSynchronization> suspendedSynchronizations = doSuspendSynchronization();
try {
Object suspendedResources = null;
if (transaction != null) {
//挂起当前事务，即删除threadLocal存储的DataSource与当前连接的映射关系
suspendedResources = doSuspend(transaction);
}
String name = TransactionSynchronizationManager.getCurrentTransactionName();
TransactionSynchronizationManager.setCurrentTransactionName(null);
boolean readOnly = TransactionSynchronizationManager.isCurrentTransactionReadOnly();
TransactionSynchronizationManager.setCurrentTransactionReadOnly(false);
Integer isolationLevel = TransactionSynchronizationManager.getCurrentTransactionIsolationLevel();
TransactionSynchronizationManager.setCurrentTransactionIsolationLevel(null);
boolean wasActive = TransactionSynchronizationManager.isActualTransactionActive();
TransactionSynchronizationManager.setActualTransactionActive(false);
//保存被挂起事务，等待之后恢复
return new SuspendedResourcesHolder(
suspendedResources, suspendedSynchronizations, name, readOnly, isolationLevel, wasActive);
}
catch (RuntimeException | Error ex) {
// doSuspend failed - original transaction is still active...
doResumeSynchronization(suspendedSynchronizations);
throw ex;
}
}
else if (transaction != null) {
// Transaction active but no synchronization active.
Object suspendedResources = doSuspend(transaction);
return new SuspendedResourcesHolder(suspendedResources);
}
else {
// Neither transaction nor synchronization active.
return null;
}
}
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# 事务回滚
TransactionAspectSupport#completeTransactionAfterThrowing
protected void completeTransactionAfterThrowing(@Nullable TransactionInfo txInfo, Throwable ex) {
if (txInfo != null && txInfo.getTransactionStatus() != null) {
//是需要回滚的异常
if (txInfo.transactionAttribute != null && txInfo.transactionAttribute.rollbackOn(ex)) {
try {
txInfo.getTransactionManager().rollback(txInfo.getTransactionStatus());
}
//catch ...
}
else {
// 不是匹配的异常，提交
// 提交的时候，还会检查事务是否被标记为回滚
try {
txInfo.getTransactionManager().commit(txInfo.getTransactionStatus());
}
//catch ...
}
}
}
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AbstractPlatformTransactionManager.processRollback
private void processRollback(DefaultTransactionStatus status, boolean unexpected) {
try {
boolean unexpectedRollback = unexpected;
try {
//预留自定义方法的钩子
triggerBeforeCompletion(status);
if (status.hasSavepoint()) {
if (status.isDebug()) {
logger.debug("Rolling back transaction to savepoint");
}
//回滚到保存点
status.rollbackToHeldSavepoint();
}
else if (status.isNewTransaction()) {
if (status.isDebug()) {
logger.debug("Initiating transaction rollback");
}
//新事务，直接回滚
doRollback(status);
}
else {
// Participating in larger transaction
if (status.hasTransaction()) {
// globalRollbackOnParticipationFailure 默认是true，可以在注册DataSourceTransactionManager时修改
if (status.isLocalRollbackOnly() || isGlobalRollbackOnParticipationFailure()) {
//标记连接需要回滚
doSetRollbackOnly(status);
}
else {
// log ...
}
}
else {
logger.debug("Should roll back transaction but cannot - no transaction available");
}
// 尽早抛出异常，默认是false
if (!isFailEarlyOnGlobalRollbackOnly()) {
unexpectedRollback = false;
}
}
}
catch (RuntimeException | Error ex) {
triggerAfterCompletion(status, TransactionSynchronization.STATUS_UNKNOWN);
throw ex;
}
//预留自定义方法的钩子
triggerAfterCompletion(status, TransactionSynchronization.STATUS_ROLLED_BACK);
// Raise UnexpectedRollbackException if we had a global rollback-only marker
if (unexpectedRollback) {
throw new UnexpectedRollbackException(
"Transaction rolled back because it has been marked as rollback-only");
}
}
finally {
//事务完成后的清理
cleanupAfterCompletion(status);
}
}
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# 提交事务
AbstractPlatformTransactionManager.commit
public final void commit(TransactionStatus status) throws TransactionException {
if (status.isCompleted()) {
throw new IllegalTransactionStateException(
"Transaction is already completed - do not call commit or rollback more than once per transaction");
}
DefaultTransactionStatus defStatus = (DefaultTransactionStatus) status;
//已被标记成回滚
if (defStatus.isLocalRollbackOnly()) {
processRollback(defStatus, false);
return;
}
//defStatus.isGlobalRollbackOnly()会检查ConnectionHolder是否被设置成回滚
if (!shouldCommitOnGlobalRollbackOnly() && defStatus.isGlobalRollbackOnly()) {
if (defStatus.isDebug()) {
logger.debug("Global transaction is marked as rollback-only but transactional code requested commit");
}
//这里传true 回滚后会抛异常 Transaction rolled back because it has been marked as rollback-only
processRollback(defStatus, true);
return;
}
processCommit(defStatus);
}
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AbstractPlatformTransactionManager.processCommit
private void processCommit(DefaultTransactionStatus status) throws TransactionException {
try {
boolean beforeCompletionInvoked = false;
try {
boolean unexpectedRollback = false;
//空实现
prepareForCommit(status);
//预留自定义方法的钩子
triggerBeforeCommit(status);
triggerBeforeCompletion(status);
beforeCompletionInvoked = true;
//还存在保存点，需要释放保存点
if (status.hasSavepoint()) {
unexpectedRollback = status.isGlobalRollbackOnly();
status.releaseHeldSavepoint();
}
//新事务 即最开始创建的 才执行提交
else if (status.isNewTransaction()) {
unexpectedRollback = status.isGlobalRollbackOnly();
doCommit(status);
}
else if (isFailEarlyOnGlobalRollbackOnly()) {
unexpectedRollback = status.isGlobalRollbackOnly();
}
// Throw UnexpectedRollbackException if we have a global rollback-only
// marker but still didn't get a corresponding exception from commit.
if (unexpectedRollback) {
throw new UnexpectedRollbackException(
"Transaction silently rolled back because it has been marked as rollback-only");
}
}
catch (UnexpectedRollbackException ex) {
// can only be caused by doCommit
triggerAfterCompletion(status, TransactionSynchronization.STATUS_ROLLED_BACK);
throw ex;
}
catch (TransactionException ex) {
// can only be caused by doCommit
if (isRollbackOnCommitFailure()) {
doRollbackOnCommitException(status, ex);
}
else {
triggerAfterCompletion(status, TransactionSynchronization.STATUS_UNKNOWN);
}
throw ex;
}
catch (RuntimeException | Error ex) {
if (!beforeCompletionInvoked) {
triggerBeforeCompletion(status);
}
doRollbackOnCommitException(status, ex);
throw ex;
}
// Trigger afterCommit callbacks, with an exception thrown there
// propagated to callers but the transaction still considered as committed.
try {
triggerAfterCommit(status);
}
finally {
triggerAfterCompletion(status, TransactionSynchronization.STATUS_COMMITTED);
}
}
finally {
cleanupAfterCompletion(status);
}
}
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AbstractPlatformTransactionManager.cleanupAfterCompletion
private void cleanupAfterCompletion(DefaultTransactionStatus status) {
//设置事务完成
status.setCompleted();
if (status.isNewSynchronization()) {
//清理同步信息，删除ThreadLocal中保存的信息
TransactionSynchronizationManager.clear();
}
if (status.isNewTransaction()) {
doCleanupAfterCompletion(status.getTransaction());
}
if (status.getSuspendedResources() != null) {
if (status.isDebug()) {
logger.debug("Resuming suspended transaction after completion of inner transaction");
}
Object transaction = (status.hasTransaction() ? status.getTransaction() : null);
resume(transaction, (SuspendedResourcesHolder) status.getSuspendedResources());
}
}
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DataSourceTransactionManager.doCleanupAfterCompletion
protected void doCleanupAfterCompletion(Object transaction) {
DataSourceTransactionObject txObject = (DataSourceTransactionObject) transaction;
// Remove the connection holder from the thread, if exposed.
if (txObject.isNewConnectionHolder()) {
//释放当前线程绑定的数据库连接
TransactionSynchronizationManager.unbindResource(obtainDataSource());
}
// Reset connection.
Connection con = txObject.getConnectionHolder().getConnection();
try {
//恢复成自动提交
if (txObject.isMustRestoreAutoCommit()) {
con.setAutoCommit(true);
}
//恢复成数据库默认配置
DataSourceUtils.resetConnectionAfterTransaction(
con, txObject.getPreviousIsolationLevel(), txObject.isReadOnly());
}
catch (Throwable ex) {
logger.debug("Could not reset JDBC Connection after transaction", ex);
}
if (txObject.isNewConnectionHolder()) {
//释放连接，会调用数据库连接的close方法
//但是不一定真的会关闭连接，使用连接池获取的连接是一个代理连接，会有自己实现的放入连接池操作
DataSourceUtils.releaseConnection(con, this.dataSource);
}
txObject.getConnectionHolder().clear();
}
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编辑 (opens new window)
上次更新: 2023/04/09, 16:34:32