springmvc源碼深度解析之攔截器過濾器視圖層分析

Spring5.0源碼深度解析課程安Spring5.0事務源碼分Spring5.0AopSpring5.0、SpringMVCSpringBoot2.0余老 Spring框架快速入什么Spring框SpringJavaIoC(InversionofControlAOP(AspectOrientedProgramming，面NewUserService();Spring體系結1、SpringCore：BeanFactoryJavaBean（IOC）模式將應用程序的配置和依賴性規(guī)范與實際的應用程序代碼分開。2、SpringAOP：集成了面向切面的編程功能（AOP可以將性事物管理集成到應用程序中。3、SpringCntext：一個配置文件，為Spring框架提供上下文信息4、SpringDo：Spring5、SpringORM：Spring集成了各種orm（objectrelationshipmap對象關系映射6、SpringWebweb（Struts、7、SpringwebMVC：Springweb思考一個問題為什么啟動SpringBoot項目的時候需要加上Configuration快速構建Spring環(huán)Maven依賴信<artifactId>spring-Xml方式環(huán)境搭<beanid="userEntity"<beanid="userEntity"<propertyname="userId"<propertyname="userName"<beans" " " bean對publicclasspublicclassUserEntity{privateIntegeruserId;privateStringuserName;publicUserEntity(IntegeruserId,StringuserName)this.userId=this.userName=}publicvoidsetUserId(IntegeruserId)this.userId=}publicvoidsetUserName(StringuserName)this.userName=}publicStringtoString()return"UserEntity{""userId="+userId",userName='"+userName+'\''}}Spring啟動 spring配置文件,IOC容ClassPathXmlApplicationContextclassPath=new//UserEntityuserEntity=(UserEntity)classPath.getBean("userEntity");注解方式環(huán)境搭Configuration配置容publicpublicclassMySpringConfig//@Configuration等同于配置的spring配置文publicUserEntityuserEntity()returnnewUserEntity(10,}}publicclassUserEntity{privateIntegeruserId;privateStringuserName;publicUserEntity(IntegeruserId,StringuserName)this.userId=this.userName=}publicIntegergetUserId()return}publicStringgetUserName()return}publicvoidsetUserId(IntegeruserId)this.userId=}publicpublicvoidsetUserName(StringuserName)this.userName=}}使用注解形式形式加載privateprivatestaticAnnotationConfigApplicationContextpublicstaticvoidmain(String[]args)applicationContext=newAnnotationConfigApplicationContext(MySpringConfig.class);UserEntityuserEntity=applicationContext.getBean("userEntity",UserEntity.class);}@ComponentScan用掃包下注入springIOC容器publicclassMySpringConfig{//@Configuration等同于配spring配置文publicUserEntityuserEntity()returnnewUserEntity(10,}}privateprivatestaticAnnotationConfigApplicationContextpublicstaticvoidmain(String[]args)annotationConfigApplicationContextannotationConfigApplicationContext=newAnnotationConfigApplicationContext(MySpringConfig.class);UserServiceuserService=annotationConfigApplicationContext.getBean("userService",UserService.class);System.out.println("userService:"+userService);System.out.println("以下為IOC容器注入成功的對象String[]beanDefinitionNames=for(inti=0;i<beanDefinitionNames.length;i++){}}FilterType有四種類型ASPECTJAspectj@ComponentScan(value@ComponentScan(value="com.mayikt.v2",includeFilters={@ComponentScan.Filter(type=FilterType.ANNOTATION,=Controller.class)},useDefaultFilters=false)publicclassMySpringConfig{//@Configuration等同于配spring配置文publicUserEntityuserEntity()returnnewUserEntity(10,}}@ComponentScan(value@ComponentScan(value="com.mayikt.v2",excludeFilters={@ComponentScan.Filter(type=FilterType.ANNOTATION,=Controller.class)},useDefaultFilters=true)publicclassMySpringConfig{//@Configuration等同于配spring配置文publicUserEntityuserEntity()returnnewUserEntity(10,}}}SpringsingletonprototypeBeanrequestBeanBeanHttp請session作用域表示煤氣請求都會產生一個新的BeanBean僅在當前HttpUserServiceUserServiceuserService1=annotationConfigApplicationContext.getBean("userService",UserServiceuserService2=annotationConfigApplicationContext.getBean("userService",結果為Lazy表示為懶加載，當真正需要獲取的時候才會被加True表示為懶加載false表示為在IOC容器加載的時候被創(chuàng)建publicclassUserServicepublicUserService()System.out.println("UserService無參數構造被加載}}}Condition是在spring4.0增加的條件注解，通過這個可以功能可以實現選擇性的注入Bean操作，接下來先學習下Condition是如何使用的，然后分析spring源碼了解其中的實SpringWIN7win7publicpublicclassMyConditionimplementsCondition根據條件判斷上下文*@param@parampublicbooleanmatches(ConditionContextcontext,AnnotatedTypeMetadatametadata)1.獲取當前環(huán)境配Environmentenvironment=context.getEnvironment();StringosName=environment.getProperty("");if(osName.equals("Windows7")){true就是能夠創(chuàng)建該return}return}}publicWin7Entitywin7Entity(){returnnew}@Import注@Import@Configurationbean@Import({V5UserEntity.class,默 beanid@Import({V5UserEntity.class,publicpublicclassMyImportSelectorimplementsImportSelectorAnnotationMetadata注解信*@param//添加需 的spring容器的returnnew}}@public@interfaceEnableUser}publicclassMyImportBeanDefinitionRegistrarimplementspublicclassMyImportBeanDefinitionRegistrarimplementsImportBeanDefinitionRegistrarpublicpublicvoidregisterBeanDefinitions(AnnotationMetadataimportingClassMetadata,BeanDefinitionRegistryregistry)//手 StringbeanName=RootBeanDefinitionrootBeanDefinition=newRootBeanDefinition(PayEntity.class);registry.registerBeanDefinition(beanName,rootBeanDefinition);}}publicpublicclassMyFactoryBeanimplementsFactoryBean<MemberEntity>publicMemberEntitygetObject()throwsExceptionreturnnew}publicClass<?>getObjectType()return}publicbooleanisSingleton()return}}publicMyFactoryBeanmyFactoryBean()returnnew}區(qū)別：BeanFactory是個Factory，也就是IOC容器或對象工廠，FactoryBean是個Bean。SpringBeanBeanFactoryIOCFactoryBean而言，這個Bean不是簡單的Bean，而是一個能生產或者修飾對象生成的工廠SpringBean的生命周期總refresh();getBean()→doGetBean()→createBean()→doCreateBean()→createBeanInstance(初始化對JavaCGLIBinvokeAwareMethods()awareapplyBeanPostProcessorsAfterInitializationSpringAop源碼分AspectJAutoProxyRegistrar中會對象BeanClass：AnnotationAwareAspectJAutoProxyCreatorAutoProxyCreator有是 AutoProxyCreator經過這樣的一個類。判斷該被對象是否有被有實現過接口，如果有實現過接口就使用jdk動態(tài)，如果沒有實現接口則使用cglib動態(tài)。MethodInterceptor（每個通知）invoke模擬SpringAop五個通知調用鏈關UserService接publicpublicclassUserServicepublicvoidlogin(StringuserName,Stringage){System.out.println("userName:"+userName+",age:"+age);}}創(chuàng)建方法接publicpublicinterfaceMethodInterceptor執(zhí)行通知*@paramObjectinvoke(MethodInvocationmethodInvocation)throwsInvocationTargetException,}創(chuàng)建前置通publicpublicclassBeforMethodInterceptorimplementsMethodInterceptorpublicObjectinvoke(MethodInvocationmethodInvocationthrowsInvocationTargetExceptionIllegalAccessExceptionreturnmethodIcess();//目標方}}創(chuàng)建后置通publicpublicclassAfterMethodInterceptorimplementsMethodInterceptorpublicObjectinvoke(MethodInvocationmethodInvocation)InvocationTargetException,IllegalAccessExceptionObjectprocessmethodIcess();return}}創(chuàng)建環(huán)繞通publicpublicclassAroundMethodInterceptorimplementsMethodInterceptorpublicObjectinvoke(MethodInvocationmethodInvocation)throwsInvocationTargetException,IllegalAccessException{ Objectprocess=System.out.println("環(huán)繞通知之后執(zhí) return}}創(chuàng)建方法執(zhí)行接publicpublicinterfaceMethodInvocation方法調用個通知的方*Objectprocess()throwsInvocationTargetException,}publicclassDefaultMethodInvacationimplementsMethodInvocationprivateList<MethodInterceptor>chian;privateObjecttarget;//目標對象privateMethodmethod;//目標方法privateObjectargs[];//目標參數publicDefaultMethodInvacation(List<MethodInterceptor>chian,Objecttarget,Methodmethod,Object[]args)this.chian=chian;this.target=target;this.method=method;this.args=args;}publicObjectprocess()throwsInvocationTargetException,IllegalAccessExceptionif(currentChianIndex==chian.size())執(zhí)行目標returnreturnmethod.invoke(target,}MethodInterceptormethodInterceptor=//return}}Spring事務底層源碼分SpringAop基本環(huán)境搭Maven依賴信<artifactId>spring-mysql<artifactId>mysql-connector-<artifactId>spring-publicclassMyConfig{publicDataSourcedataSource()MysqlDataSourcemysqlDataSource=newMysqlDataSource();return}publicJdbcTemplatejdbcTemplate()returnnew}publicPlatformTransactionManagertxManager()returnnew}}publicclassOrderDao{privateJdbcTemplatepublicvoidaddOrderInfo()jdbcTemplate.update("insertintoorder_info}}Spring事務源碼分Aop實現一樣的功能。Ioc容器中TransactionInterceptor是 ifif(txAttr==null||!(tminstanceofCallbackPreferringPlatformTransactionManager))開啟事TransactionInfotxInfo=createTransactionIfNecessary(tm,txAttr,joinpointIdentification);ObjectretVal=null;try執(zhí)行目標方retVal=}catch(Throwableex)//回滾當前事務completeTransactionAfterThrowing(txInfo,ex);throwex;}finally}returnretVal;}純手寫SpringAop環(huán)繞通知+手動事務就可以事SpringAop中所有最終是如何執(zhí)行？調用鏈關AutoProxyCreator使用該類創(chuàng)建目標對象（TransactionInterceptor事務@EnableTransactionManagementePROXY: Beanid:Value:ProxyTransactionManagementConfiguration將一下對象到ioc容Value:tansactionInterceptorInfrastructureAdvisorAutoProxyCreator就是我們的后置處理Bean對象在初始化之后都會判斷是否需要創(chuàng)建類（根據是否有加上InfrastructureAdvisorAutoProxyCreator就 serviceSpring循環(huán)依賴原什么Spring循環(huán)依賴問如何解決Spring循環(huán)依賴相關業(yè)務邏輯代publicclassAService{ privateBServicepublicvoidsetbService(BServicebService)this.bService=}}publicclassBService{ privateAServicepublicvoidsetaService(AServiceaService)this.aService=}}如何底層解決循環(huán)依賴原循環(huán)依賴中完整對象信Map<String,Object>singletonObjects一級緩存完成對象（對象和屬性都已經賦值）Map<String,Object>earlySingletonObjects性缺沒有賦值早期對象Map<String,ObjectFactory<?>>singletonFactories三級緩存(只初始化，沒有給屬性賦值對象)存放提前對象AB依賴與BBAASpringBeanA（單例的情況doGetBeanStringbeanNameStringbeanNameObjectFactory<?>singletonFactorycreateBean→doCreateBeancreateBeanInstancecglib（注意對象不完整，因為熟悉沒有duGetBean1-6BAgetSingletonAapplyPropertyValues→valueResolver.resolveValueIfNecessary→resolveReference(argName,ref)init（初始化HashMap<Object,HashMap<Object,Object>objectHashMap=newHashMap<Object,1.A對objectHashMap.put("aService",new//2.B對象從三級緩存中查找到objectHashMap.put("bService",newAServiceaService=(AService)objectHashMap.get("aService");BServicebService=(BService)objectHashMap.get("bService");bService.aService=aService;//3.A對象需要設aService.bService=protectedprotectedObjectgetSingleton(StringbeanName,booleanallowEarlyReference)1.ObjectsingletonObject=//2.沒有創(chuàng)建對象，并且該對象正在創(chuàng)建（標記為循環(huán)依賴的查詢if(singletonObject==null&&isSingletonCurrentlyInCreation(beanName))//3.singletonObject=this.earlySingletonObjects.get(beanName);if(singletonObject==null&&allowEarlyReference){//4.ObjectFactory<?>singletonFactory=this.singletonFactories.get(beanName);if(singletonFactory!=null){singletonObject=singletonFactory.getObject();this.earlySingletonObjects.put(beanName,singletonObject);}}}}returnprotectedprotectedvoidaddSingletonFactory(StringbeanName,ObjectFactory<?>singletonFactory){Assert.notNull(singletonFactory,"Singletonfactorymustnotbenull");if(!this.singletonObjects.containsKey(beanName)){this.singletonFactories.put(beanName,singletonFactory);}}}，BAABBAbeaniscurrentlyincreation:IsthereanunresolvablecircularABBABBABABAABSpringBean創(chuàng)建AdoGetBeangetSingleton（StringgetSingleton(StringbeanName,ObjectFactory<?>singletonFactory)this.singletonsCurrentlyInCreation.add(beanName)createBeanInstancecglibbeanaddSingletonFactorypopulateBeanABBBAprotectedvoidaddSingleton(StringbeanName,ObjectsingletonObject){synchronized(this.singletonObjects){this.singletonObjects.put(beanName,publicObjectprotectedprotectedvoidaddSingletonFactory(StringbeanName,ObjectFactory<?>singletonFactory){Assert.notNull(singletonFactory,"Singletonfactorymustnotbenull");//判斷一級緩存是否存if(!this.singletonObjects.containsKey(beanName))//將該不完整的對象存放到三級緩存集合中this.singletonFactories.put(beanName,singletonFactory);}}}protectedprotectedObjectgetSingleton(StringbeanName,booleanallowEarlyReference)//1.一級緩存bean對象該集合緩存的對象為完整對象對象創(chuàng)建完畢并且已經屬性賦值成功ObjectsingletonObject=if(singletonObject==null&&isSingletonCurrentlyInCreation(beanName))//2.從二級緩存中獲取對象信singletonObject=this.earlySingletonObjects.get(beanName);if(singletonObject==null&&allowEarlyReference){3.從三級緩存中獲取對ObjectFactory<?>singletonFactory=this.singletonFactories.get(beanName);if(singletonFactory!=null){singletonObjectsingletonObject=//4.如果三級緩存中存在對象的時候下，就返回二級緩存中。this.earlySingletonObjects.put(beanName,singletonObject);}}}}return}SpringIOCAOP依賴注入賦值ABB對象BAAspringSpringBeanAservicgetSingleton（beanName）singletonObjects一級緩存完整對象earlySingletonObjectssingletonFactories三級緩存存放嬰兒對象嬰兒對象（提前對象）{}singletonsCurrentlyInCreationgetSingleton(StringbeanName,ObjectFactory<?>singletonFactory)this.singletonsCurrentlyInCreation.add(beanName)表示該對象已經開始創(chuàng)建createBean() 賦值的）存放三級緩存中。ABABBprotectedprotectedvoidaddSingletonFactory(StringbeanName,ObjectFactory<?>singletonFactory){Assert.notNull(singletonFactory,"Singletonfactorymustnotbenull");//如果一級緩存沒有該對象的情if(!this.singletonObjects.containsKey(beanName))//將該對象存放到三級緩存中嬰兒對象this.singletonFactories.put(beanName,singletonFactory);}}}protectedprotectedObjectgetSingleton(StringbeanName,booleanallowEarlyReference)//1.一級緩存對象集合（緩存完整對象）對象已經創(chuàng)建成功呢并且所有的屬性都已經賦值成ObjectsingletonObject=2.如果已經緩存沒if(singletonObject==null&&isSingletonCurrentlyInCreation(beanName))//查詢二級緩存是否有緩存對singletonObject=this.earlySingletonObjects.get(beanName);if(singletonObject==null&&allowEarlyReference){//4.查詢三級緩存，三級緩存如果有的情況ObjectFactory<?>singletonFactory=this.singletonFactories.get(beanName);if(singletonFactory!=null){singletonObject=//將三級緩存中的數據放入到二級緩存中this.earlySingletonObjects.put(beanName,singletonObject);}}}}return}SpringMVC源碼分Servlet開發(fā)基本環(huán)Servlet簡單的介SunAPIservletwebJava2ServletServletSpringMVC關idea快速創(chuàng)建一個Servlet項創(chuàng)建的mavenweb工廠發(fā)現沒有 ，則創(chuàng)建XML方 publicclassMyServletextendsHttpServletprotectedvoiddoGet(HttpServletRequestreq,HttpServletResponseresp)ServletException,IOException{resp.getWriter().print("thisismayikt");}}基于注解方publicclassMyServletextendsHttpServletprotectedvoiddoGet(HttpServletRequestreq,HttpServletResponseresp)ServletException,IOException{resp.getWriter().print("thisismayikt");}}Servlet線程是否答案：不安全，Servlet是單例的在高并況下，可能會存程安全問publicclassMyServletextendsHttpServletprivateIntegercount=publicMyServlet(){}protectedvoiddoGet(HttpServletRequestreq,HttpServletResponseresp)throwsServletException,IOExceptiontry{}catch(Exceptione)}resp.getWriter().print("thisismayiktcount:"+}}在web容器啟動時為提供給第組件機會做一些初始化的工作，例如servlet或filtes等，servletServletContainerInitializer每個框架要使用ServletContainerInitializer就必須在對應的jar包的META-INF/services 建一個名為javax.servlet.ServletContainerInitializer的文件，文件內容指定具體的ServletContainerInitializer實現類。1、Servlet容器掃描，當前應用里面每一個jar包ServletContainerInitializer2ServletContainerInitializerServletContainerInitializer實現類的全類名；相關代@author螞蟻課堂創(chuàng)始人@title:@description:每特教育獨創(chuàng)第五期互聯網架構課@date@HandlesTypes(value=publicclassMyServletContainerInitializerimplementsServletContainerInitializer*@param 類型也就是MyHandlesType所有子類@param@throwspublicvoidonStartup(Set<Class<?>>set,ServletContextservletContext)throwsServletException//1.打印所有 的類forfor(Class<?>c:set){}//2.servletContext手動過濾器 ServletRegistration.DynamicpayServlet=servletContext.addServlet("payServlet",newPayServlet());}}基于xml方式啟Maven依賴信publicclassMyMvcConfig}配置文件內publicpublicclassWebInitializerimplementsWebApplicationInitializerpublicvoidonStartup(javax.servlet.ServletContextservletContext)ServletException 創(chuàng)建SpringMVC容AnnotationConfigWebApplicationContextapp=//2.我們的配置文 我們DispatcherServletdispatcherServlet=newDispatcherServlet(app);ServletRegistration.Dynamicdynamic=servletContext.addServlet("dispatcherServlet",dispatcherServlet);dynamic.setLoadOnStartup(1);//最優(yōu)先啟}}}Jsp視圖publicpublicViewResolverviewResolver()InternalResourceViewResolverinternalResourceViewResolver=new前internalResourceViewResolver.setPrefix("/WEB-//后綴returninternalResourceViewResolver;}<%@pagelanguage="java"contentType="text/html;charset=UTF-我是完全注解方式整合SpringMVC器使用器和過濾器都是基于Aop實現，能夠對請求執(zhí)行之前和之后實現。ServletWeb器不需要依賴于Servlet、不僅可以實現Web請求還有其他方法等SpringMVC器的使1.自定義請求pletion在DispatcherServletpublicpublicclassTokenInterceptorimplementsHandlerInterceptorpublicbooleanpreHandle(HttpServletRequestrequest,HttpServletResponsere