springMVC源码分析初始化过程

springMVC初始化

在分析具体的url请求之前,需要了解springMVC环境(spring的web容器)如何进行初始化的

实例代码

package com;
@Configuration
@ComponentScan("com.mvc")
@EnableWebMvc
public class AppConfig implements WebMvcConfigurer {
    //视图解析
    @Override
    public void configureViewResolvers(ViewResolverRegistry registry) {
        registry.jsp( "/app/",".html" );
    }
    //消息转换
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        converters.add( new FastJsonHttpMessageConverter() );
    }
}


package com.initializer;
public class MyWebApplicationInitializer implements WebApplicationInitializer {
    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        //初始化spring 容器
        AnnotationConfigWebApplicationContext ac = new AnnotationConfigWebApplicationContext();
        ac.register( AppConfig.class);
        DispatcherServlet servlet = new DispatcherServlet(ac);
        ServletRegistration.Dynamic registration = servletContext.addServlet("app", servlet);
        registration.setLoadOnStartup(1);
        registration.addMapping("*.do");
    }
}

package com.mvc;
@Component("/name.do") 
public class BeanNameController implements Controller {
    @Override
    public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
        System.out.println("beanName---Controller");
        return null;
    }
}

package com.mvc;
@Component("/name1.do") 
public class HandleController implements HttpRequestHandler {
    @Override
    public void handleRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        System.out.println("beanname-------HttpRequestHandler");
    }
}

package com.mvc;
@Controller
public class TestController {
    @RequestMapping("/test.do")
    @ResponseBody                                                 
    public Object test(String name, HttpServletRequest request, HttpServletResponse response ){
        request.getParameter("name");
        Map hashMap = new HashMap();
        hashMap.put("key","value");
        return  hashMap;
    }

    @RequestMapping("/model.do")
    public String model(HttpServletRequest request,HttpServletResponse response){
        // /app/index.html
        return "index";
    }
}

debug分析

springMVC初始化,是从tomcat初始化servlet开始。具体如何开始执行servlet需要tomcat源码。在这里只分析tomcat启动后初始化Servlet在springweb容器的实现流程,从HttpServletBean的init方法开始
HttpServletBean的全路径是org.springframework.web.servlet.HttpServletBean (spring实现)
HttpServlet的全路径是javax.servlet.http.HttpServlet (jdk)
HttpServletBean继承了HttpServlet

init

HttpServletBean#init 初始化方法init


init.png
initServletBean

FrameworkServlet#initServletBean 初始化ServletBean


initServletBean.png
initWebApplicationContext

FrameworkServlet#initWebApplicationContext 初始化WebApplicationContext(web应用上下文---spring形式的web环境)


initWebApplicationContext.png
configureAndRefreshWebApplicationContext

FrameworkServlet#configureAndRefreshWebApplicationContext配置和刷新Refresh web环境


configureAndRefreshWebApplicationContext.png
refresh

AbstractApplicationContext#refresh 这个方法刷新spring web容器
finishBeanFactoryInitialization()方法实例化所有不是lazy的单例对象


refresh.png
实例化

具体的实例化过程经历完整的bean的生命周期,后面再单独介绍。

handlerMap集合添加

对beanName或alias是以/开头
由于BeanNameUrlHandlerMapping实现了ApplicationContextAware方法,会执行initApplicationContext方法
对于beanName是beanNameHandlerMapping

initializeBean

AbstractAutowireCapableBeanFactory#initializeBean(String,Object, RootBeanDefinition)


applyBeanPostProcessorsBeforeInitialization.png
applyBeanPostProcessorsBeforeInitialization

AbstractAutowireCapableBeanFactory#applyBeanPostProcessorsBeforeInitialization


applyBeanPostProcessorsBeforeInitialization2.png
postProcessBeforeInitialization

ApplicationContextAwareProcessor#postProcessBeforeInitialization


postProcessBeforeInitialization.png
invokeAwareInterfaces

ApplicationContextAwareProcessor#invokeAwareInterfaces


invokeAwareInterfaces.png
setApplicationContext

ApplicationObjectSupport#setApplicationContext


setApplicationContext.png
initApplicationContext

WebApplicationObjectSupport#initApplicationContext


initApplicationContext.png
initApplicationContext

ApplicationObjectSupport#initApplicationContext(ApplicationContext)


initApplicationContext2.png
initApplicationContext

AbstractDetectingUrlHandlerMapping#initApplicationContext


initApplicationContext3.png
detectHandlers

AbstractDetectingUrlHandlerMapping#detectHandlers
首先通过determineUrlsForHandler方法对beanName判断以/开头(别名或beanName)


determineUrlsForHandler.png

detectHandlers.png
registerHandler

AbstractUrlHandlerMapping#registerHandler(String[], String) 对符合beanName要求的bean进行注册


registerHandler.png
registerHandler

AbstractUrlHandlerMapping#registerHandler(String, Object)


registerHandler2.png

在这里将会对所有beanName以/开头的添加。对实现Controller或HttpRequestHandler的注册

mappingRegistry集合添加

mappingRegistry内部集合其中一个是urlLookup集合
在创建bean过程中,此时对beanName是requestMappingHandlerMapping的处理
由于RequestMappingHandlerMapping实现了InitializingBean方法,所以将会在invokeInitMethods方法处理,在这里便会执行requestMappingHandlerMapping类的afterPropertiesSet方法

initializeBean

AbstractAutowireCapableBeanFactory#initializeBean
initializeBean方法是初始化bean,依次会调用后置处理器的初始化之前方法(applyBeanPostProcessorsBeforeInitialization)、执行初始化方法、后置处理器的初始化之后方法(applyBeanPostProcessorsAfterInitialization)


initializeBean.png
invokeInitMethods

AbstractAutowireCapableBeanFactory#invokeInitMethods执行实现了InitializingBean的afterPropertiesSet方法


invokeInitMethods.png
afterPropertiesSet

RequestMappingHandlerMapping#afterPropertiesSet 此时RequestMappingHandlerMapping已经放到bean工厂里面


afterPropertiesSet.png
afterPropertiesSet

AbstractHandlerMethodMapping#afterPropertiesSet RequestMappingHandlerMapping的父类执行


afterPropertiesSetsuper.png
initHandlerMethods

AbstractHandlerMethodMapping#initHandlerMethods 扫描应用环境的bean,查找并注册Handler的Method
首先判断是否需要从父容器查找,默认是detectHandlerMethodsInAncestorContexts=false。父子容器的含义:如果注册到父容器Handler的Method,在默认false的情况下将不会在父容器查找,这时只在子容器查找将会查找不到。如果设置true,将会从父容器查找,可以查到。


父子容器获取.png

遍历所有的beanName,查找符合isHandler的。带Controller或RequestMapping注解的


isHandler.png

查找Handler的Method(即是Controller的方法)
initHandlerMethods.png
detectHandlerMethods

AbstractHandlerMethodMapping#detectHandlerMethods


detectHandlerMethods.png

对方法遍历用lambda表达式进行注册HandlerMethod


lambda$detectHandlerMethods.png
registerHandlerMethod

AbstractHandlerMethodMapping#registerHandlerMethod 注册到mappingRegistry


registerHandlerMethod.png
register

MappingRegistry#register 添加到urlLookup集合


register.png

到这里完成了对添加了Controller、RequestMapping注解的处理,添加到集合urlLookup。

argumentResolvers初始化

RequestMappingHandlerAdapter 实现了InitializingBean。所以,在实例化RequestMappingHandlerAdapter 过程中,会调用到afterPropertiesSet方法。
RequestMappingHandlerAdapter#afterPropertiesSet


afterPropertiesSet.png
private List<HandlerMethodArgumentResolver> getDefaultArgumentResolvers() {
        List<HandlerMethodArgumentResolver> resolvers = new ArrayList<>();

        // Annotation-based argument resolution
        resolvers.add(new RequestParamMethodArgumentResolver(getBeanFactory(), false));
        resolvers.add(new RequestParamMapMethodArgumentResolver());
        resolvers.add(new PathVariableMethodArgumentResolver());
        resolvers.add(new PathVariableMapMethodArgumentResolver());
        resolvers.add(new MatrixVariableMethodArgumentResolver());
        resolvers.add(new MatrixVariableMapMethodArgumentResolver());
        resolvers.add(new ServletModelAttributeMethodProcessor(false));
        resolvers.add(new RequestResponseBodyMethodProcessor(getMessageConverters(), this.requestResponseBodyAdvice));
        resolvers.add(new RequestPartMethodArgumentResolver(getMessageConverters(), this.requestResponseBodyAdvice));
        resolvers.add(new RequestHeaderMethodArgumentResolver(getBeanFactory()));
        resolvers.add(new RequestHeaderMapMethodArgumentResolver());
        resolvers.add(new ServletCookieValueMethodArgumentResolver(getBeanFactory()));
        resolvers.add(new ExpressionValueMethodArgumentResolver(getBeanFactory()));
        resolvers.add(new SessionAttributeMethodArgumentResolver());
        resolvers.add(new RequestAttributeMethodArgumentResolver());

        // Type-based argument resolution
        resolvers.add(new ServletRequestMethodArgumentResolver());
        resolvers.add(new ServletResponseMethodArgumentResolver());
        resolvers.add(new HttpEntityMethodProcessor(getMessageConverters(), this.requestResponseBodyAdvice));
        resolvers.add(new RedirectAttributesMethodArgumentResolver());
        resolvers.add(new ModelMethodProcessor());
        resolvers.add(new MapMethodProcessor());
        resolvers.add(new ErrorsMethodArgumentResolver());
        resolvers.add(new SessionStatusMethodArgumentResolver());
        resolvers.add(new UriComponentsBuilderMethodArgumentResolver());

        // Custom arguments
        if (getCustomArgumentResolvers() != null) {
            resolvers.addAll(getCustomArgumentResolvers());
        }

        // Catch-all
        resolvers.add(new RequestParamMethodArgumentResolver(getBeanFactory(), true));
        resolvers.add(new ServletModelAttributeMethodProcessor(true));

        return resolvers;
    }
argumentResolversSet.png

initBinderArgumentResolvers集合

实现在RequestMappingHandlerAdapter#afterPropertiesSet方法

private List<HandlerMethodArgumentResolver> getDefaultInitBinderArgumentResolvers() {
        List<HandlerMethodArgumentResolver> resolvers = new ArrayList<>();

        // Annotation-based argument resolution
        resolvers.add(new RequestParamMethodArgumentResolver(getBeanFactory(), false));
        resolvers.add(new RequestParamMapMethodArgumentResolver());
        resolvers.add(new PathVariableMethodArgumentResolver());
        resolvers.add(new PathVariableMapMethodArgumentResolver());
        resolvers.add(new MatrixVariableMethodArgumentResolver());
        resolvers.add(new MatrixVariableMapMethodArgumentResolver());
        resolvers.add(new ExpressionValueMethodArgumentResolver(getBeanFactory()));
        resolvers.add(new SessionAttributeMethodArgumentResolver());
        resolvers.add(new RequestAttributeMethodArgumentResolver());

        // Type-based argument resolution
        resolvers.add(new ServletRequestMethodArgumentResolver());
        resolvers.add(new ServletResponseMethodArgumentResolver());

        // Custom arguments
        if (getCustomArgumentResolvers() != null) {
            resolvers.addAll(getCustomArgumentResolvers());
        }

        // Catch-all
        resolvers.add(new RequestParamMethodArgumentResolver(getBeanFactory(), true));

        return resolvers;
    }

returnValueHandlers集合

实现在RequestMappingHandlerAdapter#afterPropertiesSet方法

private List<HandlerMethodReturnValueHandler> getDefaultReturnValueHandlers() {
        List<HandlerMethodReturnValueHandler> handlers = new ArrayList<>();

        // Single-purpose return value types
        handlers.add(new ModelAndViewMethodReturnValueHandler());
        handlers.add(new ModelMethodProcessor());
        handlers.add(new ViewMethodReturnValueHandler());
        handlers.add(new ResponseBodyEmitterReturnValueHandler(getMessageConverters(),
                this.reactiveAdapterRegistry, this.taskExecutor, this.contentNegotiationManager));
        handlers.add(new StreamingResponseBodyReturnValueHandler());
        handlers.add(new HttpEntityMethodProcessor(getMessageConverters(),
                this.contentNegotiationManager, this.requestResponseBodyAdvice));
        handlers.add(new HttpHeadersReturnValueHandler());
        handlers.add(new CallableMethodReturnValueHandler());
        handlers.add(new DeferredResultMethodReturnValueHandler());
        handlers.add(new AsyncTaskMethodReturnValueHandler(this.beanFactory));

        // Annotation-based return value types
        handlers.add(new ModelAttributeMethodProcessor(false));
        handlers.add(new RequestResponseBodyMethodProcessor(getMessageConverters(),
                this.contentNegotiationManager, this.requestResponseBodyAdvice));

        // Multi-purpose return value types
        handlers.add(new ViewNameMethodReturnValueHandler());
        handlers.add(new MapMethodProcessor());

        // Custom return value types
        if (getCustomReturnValueHandlers() != null) {
            handlers.addAll(getCustomReturnValueHandlers());
        }

        // Catch-all
        if (!CollectionUtils.isEmpty(getModelAndViewResolvers())) {
            handlers.add(new ModelAndViewResolverMethodReturnValueHandler(getModelAndViewResolvers()));
        }
        else {
            handlers.add(new ModelAttributeMethodProcessor(true));
        }

        return handlers;
    }

initStrategies初始化initXXX集合

通过观察者设计模式实现
包括handlerMappings、handlerAdapters

refresh

finishBeanFactoryInitialization完成实例化之后,调用finishRefresh方法。


finishrefresh.png
finishRefresh

AbstractApplicationContext#finishRefresh 发布ContextRefreshedEvent上下文刷新事件


finishrefresh.png
publishEvent

AbstractApplicationContext#publishEvent(ApplicationEvent) 发布被给的事件给所有的监听者(listeners)
监听者初始化是在MessageSource之后,为了能够在监听器实现访问它,因此MessageSource实现不能发布事件


publishEvent.png
publishEvent

AbstractApplicationContext#publishEvent(Object, ResolvableType)发布被给的事件给所有的监听者(listeners)如果可能的话,使用多播


publishEvent2.png
multicastEvent

SimpleApplicationEventMulticaster#multicastEvent(ApplicationEvent, ResolvableType) 应用事件多播者广播事件。对所有的符合当前事件类型的监听器进行查找并遍历执行


SAEmulticastEvent.png
invokeListener

SimpleApplicationEventMulticaster#invokeListener 用给定的事件执行给定的监听器


invokeListener.png
doInvokeListener

SimpleApplicationEventMulticaster#doInvokeListener 监听器执行事件


doInvokeListener.png
onApplicationEvent

SourceFilteringListener#onApplicationEvent 具体监听器执行


onApplicationEvent.png
onApplicationEventInternal

SourceFilteringListener#onApplicationEventInternal 根据过滤事件源之后的实际执行事件。如果有的话,默认实现通过调用指定的委托类。
在这里首先要搞清楚SourceFilteringListener#delegate代理类是什么时候被赋值的。在执行refresh()方法之前的addApplicationListener方法。


addApplicationListener.png

创建SourceFilteringListener对象


SourceFilteringListener.png

SourceFilteringListener#onApplicationEventInternal
onApplicationEventInternal.png
onApplicationEvent

GenericApplicationListenerAdapter#onApplicationEvent 委托类执行


onApplicationEvent2.png
onApplicationEvent

ContextRefreshListener#onApplicationEvent 在FrameworkServlet的实例中对于来自servlet的WebApplicationContext(web应用上下文)的ApplicationListener,只委托给onApplicationEvent方法。FrameworkServlet.this是DispatcherServlet


onApplicationEvent3.png
onApplicationEvent

FrameworkServlet#onApplicationEvent 从这个servlet的WebApplicationContext中接收刷新事件的回调。触发刷新这个servlet的上下文相关状态


DSonApplicationEvent.png
onRefresh

DispatcherServlet#onRefresh 刷新应用上下文,这个实现调用initStrategies方法


onRefresh.png
initStrategies

DispatcherServlet#initStrategies 初始化这个servlet使用的策略对象。可以在子类中被覆盖,以便进一步初始化策略。

initStrategies.png

1、initMultipartResolver
在容器中查找beanName是multipartResolver,类型是MultipartResolver的类。结果返回空
initMultipartResolver.png

2、initLocaleResolver
在容器中查找beanName是localeResolver,类型是LocaleResolver的类。如果返回空,使用默认的AcceptHeaderLocaleResolver
initLocaleResolver.png

3、initThemeResolver
在容器中查找beanName是themeResolver,类型是ThemeResolver的类。如果返回空,使用默认的FixedThemeResolver
initThemeResolver.png

4、initHandlerMappings
DispatcherServlet#initHandlerMappings
从所有容器(父子容器)查找。类型是HandlerMapping的类,默认BeanNameUrlHandlerMapping
initHandlerMappings.png

5、initHandlerAdapters
从所有容器(父子容器)查找。类型是HandlerAdapter的类,默认SimpleControllerHandlerAdapter
initHandlerAdapters.png

6、initHandlerExceptionResolvers
类型是HandlerExceptionResolver
initHandlerExceptionResolvers.png

7、initRequestToViewNameTranslator
在容器中查找beanName是viewNameTranslator 类型是RequestToViewNameTranslator
initRequestToViewNameTranslator.png

8、initViewResolvers
DispatcherServlet#initViewResolvers
initViewResolvers.png

9、initFlashMapManager
返回SessionFlashMapManager
initFlashMapManager.png

@EnableWebMvc注解

在初始化initStrategies过程中,web容器中能够找到那么多不知道什么时候添加的HandlerMapping、HandlerAdapter等等
在实例代码中AppConfig类中使用了EnableWebMvc 注解,源码如下。
开启EnableWebMvc将会导入(import)DelegatingWebMvcConfiguration类,而DelegatingWebMvcConfiguration 继承了WebMvcConfigurationSupport 类。在WebMvcConfigurationSupport 中有18个@Bean方法

package org.springframework.web.servlet.config.annotation;
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
@Documented
@Import(DelegatingWebMvcConfiguration.class)
public @interface EnableWebMvc {
}

@Configuration
public class DelegatingWebMvcConfiguration extends WebMvcConfigurationSupport {
}



package org.springframework.web.servlet.config.annotation;
public class WebMvcConfigurationSupport implements ApplicationContextAware, ServletContextAware {

    
    @Bean
    public RequestMappingHandlerMapping requestMappingHandlerMapping() {
        RequestMappingHandlerMapping mapping = createRequestMappingHandlerMapping();
        mapping.setOrder(0);
        mapping.setInterceptors(getInterceptors());
        mapping.setContentNegotiationManager(mvcContentNegotiationManager());
        mapping.setCorsConfigurations(getCorsConfigurations());

        PathMatchConfigurer configurer = getPathMatchConfigurer();

        Boolean useSuffixPatternMatch = configurer.isUseSuffixPatternMatch();
        if (useSuffixPatternMatch != null) {
            mapping.setUseSuffixPatternMatch(useSuffixPatternMatch);
        }
        Boolean useRegisteredSuffixPatternMatch = configurer.isUseRegisteredSuffixPatternMatch();
        if (useRegisteredSuffixPatternMatch != null) {
            mapping.setUseRegisteredSuffixPatternMatch(useRegisteredSuffixPatternMatch);
        }
        Boolean useTrailingSlashMatch = configurer.isUseTrailingSlashMatch();
        if (useTrailingSlashMatch != null) {
            mapping.setUseTrailingSlashMatch(useTrailingSlashMatch);
        }

        UrlPathHelper pathHelper = configurer.getUrlPathHelper();
        if (pathHelper != null) {
            mapping.setUrlPathHelper(pathHelper);
        }
        PathMatcher pathMatcher = configurer.getPathMatcher();
        if (pathMatcher != null) {
            mapping.setPathMatcher(pathMatcher);
        }

        return mapping;
    }

    
    @Bean
    public PathMatcher mvcPathMatcher() {
        PathMatcher pathMatcher = getPathMatchConfigurer().getPathMatcher();
        return (pathMatcher != null ? pathMatcher : new AntPathMatcher());
    }

    @Bean
    public UrlPathHelper mvcUrlPathHelper() {
        UrlPathHelper pathHelper = getPathMatchConfigurer().getUrlPathHelper();
        return (pathHelper != null ? pathHelper : new UrlPathHelper());
    }


    @Bean
    public ContentNegotiationManager mvcContentNegotiationManager() {
        if (this.contentNegotiationManager == null) {
            ContentNegotiationConfigurer configurer = new ContentNegotiationConfigurer(this.servletContext);
            configurer.mediaTypes(getDefaultMediaTypes());
            configureContentNegotiation(configurer);
            this.contentNegotiationManager = configurer.buildContentNegotiationManager();
        }
        return this.contentNegotiationManager;
    }

    
    @Bean
    public HandlerMapping viewControllerHandlerMapping() {
        ViewControllerRegistry registry = new ViewControllerRegistry(this.applicationContext);
        addViewControllers(registry);

        AbstractHandlerMapping handlerMapping = registry.buildHandlerMapping();
        handlerMapping = (handlerMapping != null ? handlerMapping : new EmptyHandlerMapping());
        handlerMapping.setPathMatcher(mvcPathMatcher());
        handlerMapping.setUrlPathHelper(mvcUrlPathHelper());
        handlerMapping.setInterceptors(getInterceptors());
        handlerMapping.setCorsConfigurations(getCorsConfigurations());
        return handlerMapping;
    }
    
    @Bean
    public BeanNameUrlHandlerMapping beanNameHandlerMapping() {
        BeanNameUrlHandlerMapping mapping = new BeanNameUrlHandlerMapping();
        mapping.setOrder(2);
        mapping.setInterceptors(getInterceptors());
        mapping.setCorsConfigurations(getCorsConfigurations());
        return mapping;
    }

    
    @Bean
    public HandlerMapping resourceHandlerMapping() {
        Assert.state(this.applicationContext != null, "No ApplicationContext set");
        Assert.state(this.servletContext != null, "No ServletContext set");

        ResourceHandlerRegistry registry = new ResourceHandlerRegistry(this.applicationContext,
                this.servletContext, mvcContentNegotiationManager(), mvcUrlPathHelper());
        addResourceHandlers(registry);

        AbstractHandlerMapping handlerMapping = registry.getHandlerMapping();
        if (handlerMapping != null) {
            handlerMapping.setPathMatcher(mvcPathMatcher());
            handlerMapping.setUrlPathHelper(mvcUrlPathHelper());
            handlerMapping.setInterceptors(getInterceptors());
            handlerMapping.setCorsConfigurations(getCorsConfigurations());
        }
        else {
            handlerMapping = new EmptyHandlerMapping();
        }
        return handlerMapping;
    }


    @Bean
    public ResourceUrlProvider mvcResourceUrlProvider() {
        ResourceUrlProvider urlProvider = new ResourceUrlProvider();
        UrlPathHelper pathHelper = getPathMatchConfigurer().getUrlPathHelper();
        if (pathHelper != null) {
            urlProvider.setUrlPathHelper(pathHelper);
        }
        PathMatcher pathMatcher = getPathMatchConfigurer().getPathMatcher();
        if (pathMatcher != null) {
            urlProvider.setPathMatcher(pathMatcher);
        }
        return urlProvider;
    }


    @Bean
    public HandlerMapping defaultServletHandlerMapping() {
        Assert.state(this.servletContext != null, "No ServletContext set");
        DefaultServletHandlerConfigurer configurer = new DefaultServletHandlerConfigurer(this.servletContext);
        configureDefaultServletHandling(configurer);

        HandlerMapping handlerMapping = configurer.buildHandlerMapping();
        return (handlerMapping != null ? handlerMapping : new EmptyHandlerMapping());
    }

    
    @Bean
    public RequestMappingHandlerAdapter requestMappingHandlerAdapter() {
        RequestMappingHandlerAdapter adapter = createRequestMappingHandlerAdapter();
        adapter.setContentNegotiationManager(mvcContentNegotiationManager());
        adapter.setMessageConverters(getMessageConverters());
        adapter.setWebBindingInitializer(getConfigurableWebBindingInitializer());
        adapter.setCustomArgumentResolvers(getArgumentResolvers());
        adapter.setCustomReturnValueHandlers(getReturnValueHandlers());

        if (jackson2Present) {
            adapter.setRequestBodyAdvice(Collections.singletonList(new JsonViewRequestBodyAdvice()));
            adapter.setResponseBodyAdvice(Collections.singletonList(new JsonViewResponseBodyAdvice()));
        }

        AsyncSupportConfigurer configurer = new AsyncSupportConfigurer();
        configureAsyncSupport(configurer);
        if (configurer.getTaskExecutor() != null) {
            adapter.setTaskExecutor(configurer.getTaskExecutor());
        }
        if (configurer.getTimeout() != null) {
            adapter.setAsyncRequestTimeout(configurer.getTimeout());
        }
        adapter.setCallableInterceptors(configurer.getCallableInterceptors());
        adapter.setDeferredResultInterceptors(configurer.getDeferredResultInterceptors());

        return adapter;
    }

    
    @Bean
    public FormattingConversionService mvcConversionService() {
        FormattingConversionService conversionService = new DefaultFormattingConversionService();
        addFormatters(conversionService);
        return conversionService;
    }

    
    @Bean
    public Validator mvcValidator() {
        Validator validator = getValidator();
        if (validator == null) {
            if (ClassUtils.isPresent("javax.validation.Validator", getClass().getClassLoader())) {
                Class<?> clazz;
                try {
                    String className = "org.springframework.validation.beanvalidation.OptionalValidatorFactoryBean";
                    clazz = ClassUtils.forName(className, WebMvcConfigurationSupport.class.getClassLoader());
                }
                catch (ClassNotFoundException | LinkageError ex) {
                    throw new BeanInitializationException("Failed to resolve default validator class", ex);
                }
                validator = (Validator) BeanUtils.instantiateClass(clazz);
            }
            else {
                validator = new NoOpValidator();
            }
        }
        return validator;
    }

    
    @Bean
    public CompositeUriComponentsContributor mvcUriComponentsContributor() {
        return new CompositeUriComponentsContributor(
                requestMappingHandlerAdapter().getArgumentResolvers(), mvcConversionService());
    }


    @Bean
    public HttpRequestHandlerAdapter httpRequestHandlerAdapter() {
        return new HttpRequestHandlerAdapter();
    }

    
    @Bean
    public SimpleControllerHandlerAdapter simpleControllerHandlerAdapter() {
        return new SimpleControllerHandlerAdapter();
    }


    @Bean
    public HandlerExceptionResolver handlerExceptionResolver() {
        List<HandlerExceptionResolver> exceptionResolvers = new ArrayList<>();
        configureHandlerExceptionResolvers(exceptionResolvers);
        if (exceptionResolvers.isEmpty()) {
            addDefaultHandlerExceptionResolvers(exceptionResolvers);
        }
        extendHandlerExceptionResolvers(exceptionResolvers);
        HandlerExceptionResolverComposite composite = new HandlerExceptionResolverComposite();
        composite.setOrder(0);
        composite.setExceptionResolvers(exceptionResolvers);
        return composite;
    }

    
    @Bean
    public ViewResolver mvcViewResolver() {
        ViewResolverRegistry registry = new ViewResolverRegistry(
                mvcContentNegotiationManager(), this.applicationContext);
        configureViewResolvers(registry);

        if (registry.getViewResolvers().isEmpty() && this.applicationContext != null) {
            String[] names = BeanFactoryUtils.beanNamesForTypeIncludingAncestors(
                    this.applicationContext, ViewResolver.class, true, false);
            if (names.length == 1) {
                registry.getViewResolvers().add(new InternalResourceViewResolver());
            }
        }

        ViewResolverComposite composite = new ViewResolverComposite();
        composite.setOrder(registry.getOrder());
        composite.setViewResolvers(registry.getViewResolvers());
        if (this.applicationContext != null) {
            composite.setApplicationContext(this.applicationContext);
        }
        if (this.servletContext != null) {
            composite.setServletContext(this.servletContext);
        }
        return composite;
    }
}

所以,在导入这个类之后,这些@Bean将会使用配置类的@Bean方法进行处理


beanMethods.png

总结:

本章主要分析,request请求之前的源码级别的初始化过程。
从tomcat初始化init开始加载web级别容器上下文的初始化
1、初始化web容器上下文环境
2、EnableWebMvc注解使用Bean方法,放到web容器中
3、initApplicationContext方法,以/开头的添加到handlerMap集合
4、afterPropertiesSet方法,把Controller、RequestMapping注解方法放到mappingRegistry的集合urlLookup之中
5、argumentResolvers、initBinderArgumentResolvers、returnValueHandlers集合初始化
6、initStrategies策略,对springMVC使用的集合进行赋值。finishRefresh()完成刷新,发布事件。使用观察者设计模式(监听器)

最后编辑于
©著作权归作者所有,转载或内容合作请联系作者
禁止转载,如需转载请通过简信或评论联系作者。
  • 序言:七十年代末,一起剥皮案震惊了整个滨河市,随后出现的几起案子,更是在滨河造成了极大的恐慌,老刑警刘岩,带你破解...
    沈念sama阅读 213,752评论 6 493
  • 序言:滨河连续发生了三起死亡事件,死亡现场离奇诡异,居然都是意外死亡,警方通过查阅死者的电脑和手机,发现死者居然都...
    沈念sama阅读 91,100评论 3 387
  • 文/潘晓璐 我一进店门,熙熙楼的掌柜王于贵愁眉苦脸地迎上来,“玉大人,你说我怎么就摊上这事。” “怎么了?”我有些...
    开封第一讲书人阅读 159,244评论 0 349
  • 文/不坏的土叔 我叫张陵,是天一观的道长。 经常有香客问我,道长,这世上最难降的妖魔是什么? 我笑而不...
    开封第一讲书人阅读 57,099评论 1 286
  • 正文 为了忘掉前任,我火速办了婚礼,结果婚礼上,老公的妹妹穿的比我还像新娘。我一直安慰自己,他们只是感情好,可当我...
    茶点故事阅读 66,210评论 6 385
  • 文/花漫 我一把揭开白布。 她就那样静静地躺着,像睡着了一般。 火红的嫁衣衬着肌肤如雪。 梳的纹丝不乱的头发上,一...
    开封第一讲书人阅读 50,307评论 1 292
  • 那天,我揣着相机与录音,去河边找鬼。 笑死,一个胖子当着我的面吹牛,可吹牛的内容都是我干的。 我是一名探鬼主播,决...
    沈念sama阅读 39,346评论 3 412
  • 文/苍兰香墨 我猛地睁开眼,长吁一口气:“原来是场噩梦啊……” “哼!你这毒妇竟也来了?” 一声冷哼从身侧响起,我...
    开封第一讲书人阅读 38,133评论 0 269
  • 序言:老挝万荣一对情侣失踪,失踪者是张志新(化名)和其女友刘颖,没想到半个月后,有当地人在树林里发现了一具尸体,经...
    沈念sama阅读 44,546评论 1 306
  • 正文 独居荒郊野岭守林人离奇死亡,尸身上长有42处带血的脓包…… 初始之章·张勋 以下内容为张勋视角 年9月15日...
    茶点故事阅读 36,849评论 2 328
  • 正文 我和宋清朗相恋三年,在试婚纱的时候发现自己被绿了。 大学时的朋友给我发了我未婚夫和他白月光在一起吃饭的照片。...
    茶点故事阅读 39,019评论 1 341
  • 序言:一个原本活蹦乱跳的男人离奇死亡,死状恐怖,灵堂内的尸体忽然破棺而出,到底是诈尸还是另有隐情,我是刑警宁泽,带...
    沈念sama阅读 34,702评论 4 337
  • 正文 年R本政府宣布,位于F岛的核电站,受9级特大地震影响,放射性物质发生泄漏。R本人自食恶果不足惜,却给世界环境...
    茶点故事阅读 40,331评论 3 319
  • 文/蒙蒙 一、第九天 我趴在偏房一处隐蔽的房顶上张望。 院中可真热闹,春花似锦、人声如沸。这庄子的主人今日做“春日...
    开封第一讲书人阅读 31,030评论 0 21
  • 文/苍兰香墨 我抬头看了看天上的太阳。三九已至,却和暖如春,着一层夹袄步出监牢的瞬间,已是汗流浃背。 一阵脚步声响...
    开封第一讲书人阅读 32,260评论 1 267
  • 我被黑心中介骗来泰国打工, 没想到刚下飞机就差点儿被人妖公主榨干…… 1. 我叫王不留,地道东北人。 一个月前我还...
    沈念sama阅读 46,871评论 2 365
  • 正文 我出身青楼,却偏偏与公主长得像,于是被迫代替她去往敌国和亲。 传闻我的和亲对象是个残疾皇子,可洞房花烛夜当晚...
    茶点故事阅读 43,898评论 2 351

推荐阅读更多精彩内容