Spring 声明式事务源码学习全过程
in short 四步走
- Srping 如何从配置中加载的入口
- Spring 声明式事务的相关的 BeanDefinition加载流程
- Spring 声明式事务的相关对象创建流程
- Spring 声明式事务的拦截调用的过程(包括: 方法嵌套, 事务传播属性的处理过程)
最后再看看第三方的框架是如何支持 Spring 声明式事务, 给Spring 托管事务的
一、Spring 声明式事务的入口点
对于XML入口点
XML配置定义- <?xml version="1.0" encoding="UTF-8"?>
- <beans xmlns="http://www.springframework.org/schema/beans"
- xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
- xmlns:aop="http://www.springframework.org/schema/aop"
- xmlns:tx="http://www.springframework.org/schema/tx"
- xsi:schemaLocation="
- http://www.springframework.org/schema/beans
- https://www.springframework.org/schema/beans/spring-beans.xsd
- http://www.springframework.org/schema/tx
- https://www.springframework.org/schema/tx/spring-tx.xsd
- http://www.springframework.org/schema/aop
- https://www.springframework.org/schema/aop/spring-aop.xsd">
- <tx:annotation-driven></tx:annotation-driven>
-
- <bean id="jdbcTemplate" >
- <property name="dataSource" ref = "dataSource"></property>
- </bean>
-
- <bean id="bookService" >
- <property name="jdbcTemplate" ref="jdbcTemplate"></property>
- </bean>
-
- <bean id="dataSource" >
- <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"></property>
- <property name="url"
-
-
-
-
- </aop:config> value="jdbc:mysql://192.168.40.171:3306/workflow_test?serverTimezone=Asia/Shanghai&characterEncoding=utf8&useSSL=false"/>
- <property name="username" value="user_dev"></property>
- <property name="password" value="dev-sny.com"></property>
- </bean>
-
- <bean id="transactionManager" >
- <constructor-arg ref="dataSource"></constructor-arg>
- </bean>
-
-
-
-
-
- </aop:config>
- <tx:advice id="txAdvice" transaction-manager="transactionManager">
- <tx:attributes>
- <tx:method name="get*" read-only="true"/>
- <tx:method name="insertWithTransaction" propagation="REQUIRED" />
- <tx:method name="insertWithNoTransaction" propagation="NEVER" />
- </tx:attributes>
- </tx:advice>
- </beans>
复制代码 在XML中配置 tx:.. 启用tx标签, 在解析XML自定义标签时, 会拿到 TxNamespaceHandler 命名空间处理器, 其主要工作就是注册事务相关的标签的解析器
- tx:advice 标签解析器:负责XML相关的标签解析 TxAdviceBeanDefinitionParser
- tx:annotation-driven 标签解析器:负责注解相关的解析 AnnotationDrivenBeanDefinitionPar
org.springframework.transaction.config.TxNamespaceHandler- public class TxNamespaceHandler extends NamespaceHandlerSupport {
- static final String TRANSACTION_MANAGER_ATTRIBUTE = "transaction-manager";
- static final String DEFAULT_TRANSACTION_MANAGER_BEAN_NAME = "transactionManager";
- static String getTransactionManagerName(Element element) {
- return (element.hasAttribute(TRANSACTION_MANAGER_ATTRIBUTE) ?
-
-
-
-
- </aop:config>element.getAttribute(TRANSACTION_MANAGER_ATTRIBUTE) : DEFAULT_TRANSACTION_MANAGER_BEAN_NAME);
- }
- @Override
- public void init() {
- // <tx:advice> 标签解析器:负责解析XML <tx:advice> 事务标签配置 TxAdviceBeanDefinitionParser
- registerBeanDefinitionParser("advice", new TxAdviceBeanDefinitionParser());
- // <tx:annotation-driven> 标签解析器:负责解析注解相关的事务配置 AnnotationDrivenBeanDefinitionParser
- registerBeanDefinitionParser("annotation-driven", new AnnotationDrivenBeanDefinitionParser());
- // JTA 规范的分布式事务管理器(管理跨多个资源的事务) TODO
- registerBeanDefinitionParser("jta-transaction-manager", new JtaTransactionManagerBeanDefinitionParser());
- }
- }
复制代码 启用事务注解支持
- class AnnotationDrivenBeanDefinitionParser implements BeanDefinitionParser {
- /**
- * Parses the {@code <tx:annotation-driven/>} tag. Will
- * {@link AopNamespaceUtils#registerAutoProxyCreatorIfNecessary register an AutoProxyCreator}
- * with the container as necessary.
- */
- @Override
- @Nullable
- public BeanDefinition parse(Element element, ParserContext parserContext) {
- registerTransactionalEventListenerFactory(parserContext);
- String mode = element.getAttribute("mode");
- if ("aspectj".equals(mode)) {
- // mode="aspectj"
- registerTransactionAspect(element, parserContext);
- if (ClassUtils.isPresent("jakarta.transaction.Transactional", getClass().getClassLoader())) {
-
-
-
-
- </aop:config>registerJtaTransactionAspect(element, parserContext);
- }
- }
- else {
- // 默认是 proxy 模式
- // mode="proxy"
- AopAutoProxyConfigurer.configureAutoProxyCreator(element, parserContext);
- }
- return null;
- }
-
复制代码 注册三剑客- /**
- * Inner class to just introduce an AOP framework dependency when actually in proxy mode.
- */
- private static class AopAutoProxyConfigurer {
- public static void configureAutoProxyCreator(Element element, ParserContext parserContext) {
- AopNamespaceUtils.registerAutoProxyCreatorIfNecessary(parserContext, element);
- String txAdvisorBeanName = TransactionManagementConfigUtils.TRANSACTION_ADVISOR_BEAN_NAME;
- if (!parserContext.getRegistry().containsBeanDefinition(txAdvisorBeanName)) {
- Object eleSource = parserContext.extractSource(element);
- // Create the TransactionAttributeSource definition.
- RootBeanDefinition sourceDef = new RootBeanDefinition(
-
-
-
-
- </aop:config> "org.springframework.transaction.annotation.AnnotationTransactionAttributeSource");
- sourceDef.setSource(eleSource);
- sourceDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
- String sourceName = parserContext.getReaderContext().registerWithGeneratedName(sourceDef);
- // Create the TransactionInterceptor definition.
- RootBeanDefinition interceptorDef = new RootBeanDefinition(TransactionInterceptor.class);
- interceptorDef.setSource(eleSource);
- interceptorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
- registerTransactionManager(element, interceptorDef);
- interceptorDef.getPropertyValues().add("transactionAttributeSource", new RuntimeBeanReference(sourceName));
- String interceptorName = parserContext.getReaderContext().registerWithGeneratedName(interceptorDef);
- /**
- * 其中构建事务增强器(BeanFactoryTransactionAttributeSourceAdvisor)
- * - **Pointcut(切点)**: 默认匹配所有标注 `@Transactional` 的类 / 方法(由 `TransactionAttributeSourcePointcut` 实现)
- * - **Advice(通知)**: 即 `TransactionInterceptor`(事务拦截器)
- * - **TransactionAttributeSource(注解解析器)**:即 `AnnotationTransactionAttributeSource`, 负责解析 `@Transactional` 注解的属性(传播行为、隔离级别等)。
- */
- // Create the TransactionAttributeSourceAdvisor definition.
- RootBeanDefinition advisorDef = new RootBeanDefinition(BeanFactoryTransactionAttributeSourceAdvisor.class);
- advisorDef.setSource(eleSource);
- advisorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
- advisorDef.getPropertyValues().add("transactionAttributeSource", new RuntimeBeanReference(sourceName));
- advisorDef.getPropertyValues().add("adviceBeanName", interceptorName);
- if (element.hasAttribute("order")) {
-
-
-
-
- </aop:config>advisorDef.getPropertyValues().add("order", element.getAttribute("order"));
- }
- parserContext.getRegistry().registerBeanDefinition(txAdvisorBeanName, advisorDef);
- CompositeComponentDefinition compositeDef = new CompositeComponentDefinition(element.getTagName(), eleSource);
- compositeDef.addNestedComponent(new BeanComponentDefinition(sourceDef, sourceName));
- compositeDef.addNestedComponent(new BeanComponentDefinition(interceptorDef, interceptorName));
- compositeDef.addNestedComponent(new BeanComponentDefinition(advisorDef, txAdvisorBeanName));
- parserContext.registerComponent(compositeDef);
- }
- }
- }
复制代码 事务注解支持的三剑客
- AnnotationTransactionAttributeSource
↓(解析注解)
- TransactionInterceptor
↓(执行事务逻辑)
- BeanFactoryTransactionAttributeSourceAdvisor
↓(组装切点+通知)
总结一下XML入口, 就是无论 xml 支持 还是注解支持都会构造 org.springframework.transaction.interceptor.TransactionInterceptor 这个核心 advice 事务拦截器
对于注解的入口
- @EnableTransactionManagement
- public class TXMain {
- @Transactional
- public static void main(String[] args) throws Exception {
- System.out.println("==========================================================");
- //ApplicationContext context = new ClassPathXmlApplicationContext("application-tx.xml");
- AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(TXMain.class);
- BookService bookService = context.getBean("bookService", BookService.class);
- Book book = new Book();
- book.setName("30秒精通javascript,一分钟精通java");
- book.setCode(""+System.currentTimeMillis());
- // bookService.insertWithTransaction(book );
- bookService.insertWithNoTransaction(book);
- System.out.println("bookService = "+bookService);
- System.out.println("bookService getList = "+bookService.getList());
- System.out.println("==========================================================");
- }
- }
复制代码 @EnableTransactionManagement 注解导入了 TransactionManagementConfigurationSelector 默认选中的是 ProxyTransactionManagementConfiguration- public class TransactionManagementConfigurationSelector extends AdviceModeImportSelector<EnableTransactionManagement> {
- /**
- * Returns {@link ProxyTransactionManagementConfiguration} or
- * {@code AspectJ(Jta)TransactionManagementConfiguration} for {@code PROXY}
- * and {@code ASPECTJ} values of {@link EnableTransactionManagement#mode()},
- * respectively.
- */
- @Override
- protected String[] selectImports(AdviceMode adviceMode) {
- return switch (adviceMode) {
-
- case PROXY -> new String[] {AutoProxyRegistrar.class.getName(),
-
-
-
-
- </aop:config> ProxyTransactionManagementConfiguration.class.getName()};
- case ASPECTJ -> new String[] {determineTransactionAspectClass()};
- };
- }
- private String determineTransactionAspectClass() {
- return (ClassUtils.isPresent("jakarta.transaction.Transactional", getClass().getClassLoader()) ?
-
-
-
-
- </aop:config>TransactionManagementConfigUtils.JTA_TRANSACTION_ASPECT_CONFIGURATION_CLASS_NAME :
-
-
-
-
- </aop:config>TransactionManagementConfigUtils.TRANSACTION_ASPECT_CONFIGURATION_CLASS_NAME);
- }
- }
复制代码 同样注解的三剑客
- AnnotationTransactionAttributeSource
↓(解析注解)
- TransactionInterceptor
↓(执行事务逻辑)
- BeanFactoryTransactionAttributeSourceAdvisor
↓(组装切点+通知)
org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration- /*
- * Copyright 2002-2021 the original author or authors.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- package org.springframework.transaction.annotation;
- import org.springframework.beans.factory.config.BeanDefinition;
- import org.springframework.context.annotation.Bean;
- import org.springframework.context.annotation.Configuration;
- import org.springframework.context.annotation.ImportRuntimeHints;
- import org.springframework.context.annotation.Role;
- import org.springframework.transaction.config.TransactionManagementConfigUtils;
- import org.springframework.transaction.interceptor.BeanFactoryTransactionAttributeSourceAdvisor;
- import org.springframework.transaction.interceptor.TransactionAttributeSource;
- import org.springframework.transaction.interceptor.TransactionInterceptor;
- /**
- * {@code @Configuration} class that registers the Spring infrastructure beans
- * necessary to enable proxy-based annotation-driven transaction management.
- *
- * @author Chris Beams
- * @author Sebastien Deleuze
- * @since 3.1
- * @see EnableTransactionManagement
- * @see TransactionManagementConfigurationSelector
- */
- @Configuration(proxyBeanMethods = false)
- @Role(BeanDefinition.ROLE_INFRASTRUCTURE)
- @ImportRuntimeHints(TransactionRuntimeHints.class)
- public class ProxyTransactionManagementConfiguration extends AbstractTransactionManagementConfiguration {
- @Bean(name = TransactionManagementConfigUtils.TRANSACTION_ADVISOR_BEAN_NAME)
- @Role(BeanDefinition.ROLE_INFRASTRUCTURE)
- public BeanFactoryTransactionAttributeSourceAdvisor transactionAdvisor(
- TransactionAttributeSource transactionAttributeSource, TransactionInterceptor transactionInterceptor) {
- BeanFactoryTransactionAttributeSourceAdvisor advisor = new BeanFactoryTransactionAttributeSourceAdvisor();
- advisor.setTransactionAttributeSource(transactionAttributeSource);
- advisor.setAdvice(transactionInterceptor);
- if (this.enableTx != null) {
- advisor.setOrder(this.enableTx.<Integer>getNumber("order"));
- }
- return advisor;
- }
- @Bean
- @Role(BeanDefinition.ROLE_INFRASTRUCTURE)
- public TransactionAttributeSource transactionAttributeSource() {
- // Accept protected @Transactional methods on CGLIB proxies, as of 6.0.
- return new AnnotationTransactionAttributeSource(false);
- }
- @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;
- }
- }
复制代码 总结流程图
二、事务相关的 BeanDefinition 解析过程 (XML)
bean 标签
对于 jdbcTemplate transactionManager dataSource bookService 走的是默认命名空间的处理器, IOC标准解析流程, 不再啰嗦了
[[Spring IOC 源码学习 XML详细加载流程总结]]
org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader#parseBeanDefinitions- protected void parseBeanDefinitions(Element root, BeanDefinitionParserDelegate delegate) {
- if (delegate.isDefaultNamespace(root)) {
- NodeList nl = root.getChildNodes();
- for (int i = 0; i < nl.getLength(); i++) {
- Node node = nl.item(i);
- if (node instanceof Element ele) {//是否 是元素标签
-
-
-
-
- </aop:config>/**
-
-
-
-
- </aop:config> * 处理默认命名空间的标签, 有如下四个
-
-
-
-
- </aop:config> * <import></import>, </alias>, <bean></bean>, <beans></beans>
-
-
-
-
- </aop:config> *
-
-
-
-
- </aop:config> */
-
-
-
-
- </aop:config>if (delegate.isDefaultNamespace(ele)) {
-
-
-
-
- </aop:config> parseDefaultElement(ele, delegate);
-
-
-
-
- </aop:config>}
-
-
-
-
- </aop:config>else {
-
-
-
-
- </aop:config> /**
-
-
-
-
- </aop:config> * 处理 非默认命名空间的标签;
-
-
-
-
- </aop:config> * 注意这里包括 <context:bean ...> <tx:xx ...> 等等所有指定命名空间的xml配置
-
-
-
-
- </aop:config> * 主要逻辑是: 拿到元素的命名空间URI, 再从 XmlReaderContext 找到对应的 NamespaceHandler 调用解析 `parse`方法解析到 BeanDefinition 返回
-
-
-
-
- </aop:config> */
-
-
-
-
- </aop:config> delegate.parseCustomElement(ele);
-
-
-
-
- </aop:config>}
- }
- }
- }
- else {
- delegate.parseCustomElement(root);
- }
- }
复制代码 aop 标签
对于 aop 部分的标签则的是 AOP 的流程
- : 解析为 org.springframework.aop.aspectj.AspectJExpressionPointcut 其 BeanDefinition
- : 解析为 org.springframework.aop.support.DefaultBeanFactoryPointcutAdvisor 其 BeanDefinition
internalAutoProxyCreator 的注册
[[Spring AOP 源码学习 详细流程总结]]
这里要注意AOP 的 ConfigBeanDefinitionParser 在解析时是会注册的一个internalAutoProxyCreator! (AOP解析流程, 在BPP回调时创建代理对象的)
org.springframework.aop.config.ConfigBeanDefinitionParser#parse- @Override @Nullable public BeanDefinition parse(Element element, ParserContext parserContext) { CompositeComponentDefinition compositeDef =
-
-
-
- </aop:config>new CompositeComponentDefinition(element.getTagName(), parserContext.extractSource(element)); parserContext.pushContainingComponent(compositeDef); /** * 1. 注册一个名称为`org.springframework.aop.config.internalAutoProxyCreator` 对AOP处理的Bean Definition; 它是实现 InstantiationAwareBeanPostProcessor 接口的 * 名称是: org.springframework.aop.config.internalAutoProxyCreator * 对应的类, 根据情况有以下三个可能: org.springframework.aop.config.AopConfigUtils#APC_PRIORITY_LIST * InfrastructureAdvisorAutoProxyCreator.class,AspectJAwareAdvisorAutoProxyCreator.class, AnnotationAwareAspectJAutoProxyCreator.class * 注册一个名称为`org.springframework.aop.config.internalAutoProxyCreator` 对AOP处理的Bean Definition; 它是实现 InstantiationAwareBeanPostProcessor 接口的 * */ configureAutoProxyCreator(parserContext, element);
复制代码 解析 , , 没有切面标签
org.springframework.aop.config.ConfigBeanDefinitionParser#parse- @Override @Nullable public BeanDefinition parse(Element element, ParserContext parserContext) { CompositeComponentDefinition compositeDef =
-
-
-
- </aop:config>new CompositeComponentDefinition(element.getTagName(), parserContext.extractSource(element)); parserContext.pushContainingComponent(compositeDef); /** * 1. 注册一个名称为`org.springframework.aop.config.internalAutoProxyCreator` 对AOP处理的Bean Definition; 它是实现 InstantiationAwareBeanPostProcessor 接口的 * 名称是: org.springframework.aop.config.internalAutoProxyCreator * 对应的类, 根据情况有以下三个可能: org.springframework.aop.config.AopConfigUtils#APC_PRIORITY_LIST * InfrastructureAdvisorAutoProxyCreator.class,AspectJAwareAdvisorAutoProxyCreator.class, AnnotationAwareAspectJAutoProxyCreator.class * 注册一个名称为`org.springframework.aop.config.internalAutoProxyCreator` 对AOP处理的Bean Definition; 它是实现 InstantiationAwareBeanPostProcessor 接口的 * */ configureAutoProxyCreator(parserContext, element); /** * 2. 解析 标签的子元素 (pointcut, advisor, aspect) * 解析 : * 每一个通知(Advice) 都会封装为一个 AspectJPointcutAdvisor 的BeanDefinition 然后将其注册到 BeanFactory * * AspectJPointcutAdvisor 的包含情况 * 每一个通知(Advice) 都会封装为一个 AspectJPointcutAdvisor(通知器) 类型的BeanDefinition 然后将其注册到 BeanFactory * AspectJPointcutAdvisor 内部包含五种通知类类型: AspectJAfterReturningAdvice AspectJAfterAdvice AspectJAroundAdvice AspectJMethodBeforeAdvice AspectJAfterThrowingAdvice * 而每种通知类型的内部又主要有三个关键属性,包括: * 1. java.lang.reflect.Method(通知切面的方法) * 2. org.springframework.aop.aspectj.AspectJExpressionPointcut(切入点表达式) * 3. org.springframework.aop.aspectj.AspectInstanceFactory (切面实例工厂) */ List childElts = DomUtils.getChildElements(element); for (Element elt: childElts) { String localName = parserContext.getDelegate().getLocalName(elt); switch (localName) {
-
-
-
- </aop:config>/**
-
-
-
- </aop:config> * 解析 pointcut/切入点 //筛选连接点, 即: 哪些方法需要被代理
-
-
-
- </aop:config> * 解析为 org.springframework.aop.aspectj.AspectJExpressionPointcut 注册其 BeanDefinition
-
-
-
- </aop:config> */
-
-
-
- </aop:config>case POINTCUT -> parsePointcut(elt, parserContext);
-
-
-
- </aop:config>/**
-
-
-
- </aop:config> * 解析 advisor/通知/建议/增强处理 //即: 增强功能这一部分代码
-
-
-
- </aop:config> * 解析为 org.springframework.aop.support.DefaultBeanFactoryPointcutAdvisor 注册其 BeanDefinition
-
-
-
- </aop:config> */
-
-
-
- </aop:config>case ADVISOR -> parseAdvisor(elt, parserContext);
-
-
-
- </aop:config>/**
-
-
-
- </aop:config>
-
-
-
- </aop:config> */
-
-
-
- </aop:config>case ASPECT -> parseAspect(elt, parserContext); } } parserContext.popAndRegisterContainingComponent(); return null; }
复制代码 tx 标签
前文说了由 org.springframework.transaction.config.TxAdviceBeanDefinitionParser 负责XML解析
先来到父类方法解析 TransactionInterceptor
org.springframework.beans.factory.xml.AbstractSingleBeanDefinitionParser#parseInternal
[code]/** * Creates a {@link BeanDefinitionBuilder} instance for the * {@link #getBeanClass bean Class} and passes it to the * {@link #doParse} strategy method. * @param element the element that is to be parsed into a single BeanDefinition * @param parserContext the object encapsulating the current state of the parsing process * @return the BeanDefinition resulting from the parsing of the supplied {@link Element} * @throws IllegalStateException if the bean {@link Class} returned from * {@link #getBeanClass(org.w3c.dom.Element)} is {@code null} * @see #doParse * */ @Override protected final AbstractBeanDefinition parseInternal(Element element, ParserContext parserContext) { /** * * 1. 解析 |