springmvc源码解析之@EnableWebMvc二

时间 2019-11-06

标签 springmvc 源码解析 enablewebmvc 栏目 Spring 繁體版

原文原文链接

说在前面web

本次介绍MvcNamespaceHandler。关注“天河聊架构”更多源码解析。spring

springmvc配置解析跨域

@EnableWebMvc这个注解干了什么，初始化viewControllerHandlerMapping，初始化BeanNameUrlHandlerMapping，初始化resourceHandlerMapping缓存

进入到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#viewControllerHandlerMapping服务器

@Bean
   public HandlerMapping viewControllerHandlerMapping() {
//    注册viewControllerHandlerMapping，建立ViewControllerRegistry
      ViewControllerRegistry registry = new ViewControllerRegistry(this.applicationContext);
//    添加ViewControllers -》
      addViewControllers(registry);
//    构建HandlerMapping -》
      AbstractHandlerMapping handlerMapping = registry.buildHandlerMapping();
      handlerMapping = (handlerMapping != null ? handlerMapping : new EmptyHandlerMapping());
//    设置路径匹配器 -》
      handlerMapping.setPathMatcher(mvcPathMatcher());
//    设置url路径解析器
      handlerMapping.setUrlPathHelper(mvcUrlPathHelper());
//    设置拦截器
      handlerMapping.setInterceptors(getInterceptors());
//    设置跨域配置
      handlerMapping.setCorsConfigurations(getCorsConfigurations());
      return handlerMapping;
   }

进入到这个方法org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration#addViewControllers架构

@Override
protected void addViewControllers(ViewControllerRegistry registry) {
   this.configurers.addViewControllers(registry);
}

往上返回到这个方法org.springframework.web.servlet.config.annotation.ViewControllerRegistry#buildHandlerMappingmvc

protected SimpleUrlHandlerMapping buildHandlerMapping() {
      if (this.registrations.isEmpty() && this.redirectRegistrations.isEmpty()) {
         return null;
      }

      Map<String, Object> urlMap = new LinkedHashMap<String, Object>();
      for (ViewControllerRegistration registration : this.registrations) {
         urlMap.put(registration.getUrlPath(), registration.getViewController());
      }
      for (RedirectViewControllerRegistration registration : this.redirectRegistrations) {
         urlMap.put(registration.getUrlPath(), registration.getViewController());
      }

//    建立SimpleUrlHandlerMapping
      SimpleUrlHandlerMapping handlerMapping = new SimpleUrlHandlerMapping();
      handlerMapping.setUrlMap(urlMap);
      handlerMapping.setOrder(this.order);
      return handlerMapping;
   }

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#mvcPathMatcherapp

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

进入到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#getPathMatchConfigurercors

protected PathMatchConfigurer getPathMatchConfigurer() {
   if (this.pathMatchConfigurer == null) {
      this.pathMatchConfigurer = new PathMatchConfigurer();
      configurePathMatch(this.pathMatchConfigurer);
   }
   return this.pathMatchConfigurer;
}

进入到这个方法org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration#configurePathMatchide

@Override
protected void configurePathMatch(PathMatchConfigurer configurer) {
   this.configurers.configurePathMatch(configurer);
}

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#mvcUrlPathHelper

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

进入到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#getPathMatchConfigurer

protected PathMatchConfigurer getPathMatchConfigurer() {
   if (this.pathMatchConfigurer == null) {
      this.pathMatchConfigurer = new PathMatchConfigurer();
      configurePathMatch(this.pathMatchConfigurer);
   }
   return this.pathMatchConfigurer;
}

进入到这个方法org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration#configurePathMatch

@Override
protected void configurePathMatch(PathMatchConfigurer configurer) {
   this.configurers.configurePathMatch(configurer);
}

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#getInterceptors

protected final Object[] getInterceptors() {
      if (this.interceptors == null) {
//       建立拦截器注册器
         InterceptorRegistry registry = new InterceptorRegistry();
//       mvc配置器添加拦截器注册器
         addInterceptors(registry);
//       添加ConversionServiceExposingInterceptor 拦截器 -》
         registry.addInterceptor(new ConversionServiceExposingInterceptor(mvcConversionService()));
//       添加ResourceUrlProviderExposingInterceptor 拦截器 -》
         registry.addInterceptor(new ResourceUrlProviderExposingInterceptor(mvcResourceUrlProvider()));
//       从拦截器注册器中获取拦截器 -》
         this.interceptors = registry.getInterceptors();
      }
      return this.interceptors.toArray();
   }

这里前面介绍过了。

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#getCorsConfigurations

protected final Map<String, CorsConfiguration> getCorsConfigurations() {
      if (this.corsConfigurations == null) {
//       初始化跨域注册器
         CorsRegistry registry = new CorsRegistry();
//       添加跨域映射 -》
         addCorsMappings(registry);
//       获取跨域配置 -》
         this.corsConfigurations = registry.getCorsConfigurations();
      }
      return this.corsConfigurations;
   }

这里前面介绍过了。

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#viewControllerHandlerMapping

进入到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#beanNameHandlerMapping

@Bean
   public BeanNameUrlHandlerMapping beanNameHandlerMapping() {
//    建立BeanNameUrlHandlerMapping
      BeanNameUrlHandlerMapping mapping = new BeanNameUrlHandlerMapping();
      mapping.setOrder(2);
//    设置拦截器
      mapping.setInterceptors(getInterceptors());
//    设置跨域配置
      mapping.setCorsConfigurations(getCorsConfigurations());
      return mapping;
   }

进入到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#getInterceptors

protected final Object[] getInterceptors() {
      if (this.interceptors == null) {
//       建立拦截器注册器
         InterceptorRegistry registry = new InterceptorRegistry();
//       mvc配置器添加拦截器注册器
         addInterceptors(registry);
//       添加ConversionServiceExposingInterceptor 拦截器 -》
         registry.addInterceptor(new ConversionServiceExposingInterceptor(mvcConversionService()));
//       添加ResourceUrlProviderExposingInterceptor 拦截器 -》
         registry.addInterceptor(new ResourceUrlProviderExposingInterceptor(mvcResourceUrlProvider()));
//       从拦截器注册器中获取拦截器 -》
         this.interceptors = registry.getInterceptors();
      }
      return this.interceptors.toArray();
   }

这里前面介绍过了。

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#getCorsConfigurations

protected final Map<String, CorsConfiguration> getCorsConfigurations() {
      if (this.corsConfigurations == null) {
//       初始化跨域注册器
         CorsRegistry registry = new CorsRegistry();
//       添加跨域映射 -》
         addCorsMappings(registry);
//       获取跨域配置 -》
         this.corsConfigurations = registry.getCorsConfigurations();
      }
      return this.corsConfigurations;
   }

这里前面介绍过了。

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#beanNameHandlerMapping

进入到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#resourceHandlerMapping

@Bean
   public HandlerMapping resourceHandlerMapping() {
//    初始化resourceHandlerMapping
      Assert.state(this.applicationContext != null, "No ApplicationContext set");
      Assert.state(this.servletContext != null, "No ServletContext set");
//    建立ResourceHandlerRegistry -》
      ResourceHandlerRegistry registry = new ResourceHandlerRegistry(this.applicationContext,
            this.servletContext, mvcContentNegotiationManager(), mvcUrlPathHelper());
//    给资源handler配置器添加资源handler注册器 -》
      addResourceHandlers(registry);
//    获取handlerMapping -》
      AbstractHandlerMapping handlerMapping = registry.getHandlerMapping();
      if (handlerMapping != null) {
//       设置路径匹配器
         handlerMapping.setPathMatcher(mvcPathMatcher());
//       设置url路径匹配器
         handlerMapping.setUrlPathHelper(mvcUrlPathHelper());
//       设置url服务拦截器 -》
         handlerMapping.setInterceptors(new ResourceUrlProviderExposingInterceptor(mvcResourceUrlProvider()));
//       设置跨域
         handlerMapping.setCorsConfigurations(getCorsConfigurations());
      }
      else {
         handlerMapping = new EmptyHandlerMapping();
      }
      return handlerMapping;
   }

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#mvcContentNegotiationManager

@Bean
   public ContentNegotiationManager mvcContentNegotiationManager() {
      if (this.contentNegotiationManager == null) {
//       初始化媒体类型管理器
         ContentNegotiationConfigurer configurer = new ContentNegotiationConfigurer(this.servletContext);
//       设置默认类型 -》
         configurer.mediaTypes(getDefaultMediaTypes());
//       配置媒体类型管理器 -》
         configureContentNegotiation(configurer);
//       构建媒体类型管理器 -》
         this.contentNegotiationManager = configurer.buildContentNegotiationManager();
      }
      return this.contentNegotiationManager;
   }

这里前面介绍过了。

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#mvcUrlPathHelper

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

这里前面介绍过了。

往上返回到这个方法org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration#addResourceHandlers

@Override
protected void addResourceHandlers(ResourceHandlerRegistry registry) {
   this.configurers.addResourceHandlers(registry);
}

往上返回到这个方法org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry#getHandlerMapping

protected AbstractHandlerMapping getHandlerMapping() {
      if (this.registrations.isEmpty()) {
         return null;
      }

      Map<String, HttpRequestHandler> urlMap = new LinkedHashMap<String, HttpRequestHandler>();
      for (ResourceHandlerRegistration registration : this.registrations) {
         for (String pathPattern : registration.getPathPatterns()) {
//          获取ResourceHttpRequestHandler -》
            ResourceHttpRequestHandler handler = registration.getRequestHandler();
            if (this.pathHelper != null) {
               handler.setUrlPathHelper(this.pathHelper);
            }
            if (this.contentNegotiationManager != null) {
               handler.setContentNegotiationManager(this.contentNegotiationManager);
            }
            handler.setServletContext(this.servletContext);
            handler.setApplicationContext(this.applicationContext);
            try {
//             ResourceHttpRequestHandler加载配置
               handler.afterPropertiesSet();
            }
            catch (Throwable ex) {
               throw new BeanInitializationException("Failed to init ResourceHttpRequestHandler", ex);
            }
            urlMap.put(pathPattern, handler);
         }
      }

//    建立SimpleUrlHandlerMapping
      SimpleUrlHandlerMapping handlerMapping = new SimpleUrlHandlerMapping();
      handlerMapping.setOrder(order);
      handlerMapping.setUrlMap(urlMap);
      return handlerMapping;
   }

进入到这个方法org.springframework.web.servlet.config.annotation.ResourceHandlerRegistration#getRequestHandler

protected ResourceHttpRequestHandler getRequestHandler() {
//    建立ResourceHttpRequestHandler
      ResourceHttpRequestHandler handler = new ResourceHttpRequestHandler();
      if (this.resourceChainRegistration != null) {
//       设置ResourceResolvers -》
         handler.setResourceResolvers(this.resourceChainRegistration.getResourceResolvers());
//       设置资源转换器 -》
         handler.setResourceTransformers(this.resourceChainRegistration.getResourceTransformers());
      }
//    设置缓存相关属性
      handler.setLocationValues(this.locationValues);
      if (this.cacheControl != null) {
         handler.setCacheControl(this.cacheControl);
      }
      else if (this.cachePeriod != null) {
         handler.setCacheSeconds(this.cachePeriod);
      }
      return handler;
   }

进入到这个方法org.springframework.web.servlet.config.annotation.ResourceChainRegistration#getResourceResolvers

protected List<ResourceResolver> getResourceResolvers() {
      if (!this.hasPathResolver) {
         List<ResourceResolver> result = new ArrayList<ResourceResolver>(this.resolvers);
         if (isWebJarsAssetLocatorPresent && !this.hasWebjarsResolver) {
//          建立WebJarsResourceResolver
            result.add(new WebJarsResourceResolver());
         }
//       添加PathResourceResolver
         result.add(new PathResourceResolver());
         return result;
      }
      return this.resolvers;
   }

往上返回到这个方法org.springframework.web.servlet.config.annotation.ResourceChainRegistration#getResourceTransformers

protected List<ResourceTransformer> getResourceTransformers() {
   if (this.hasVersionResolver && !this.hasCssLinkTransformer) {
      List<ResourceTransformer> result = new ArrayList<ResourceTransformer>(this.transformers);
      boolean hasTransformers = !this.transformers.isEmpty();
      boolean hasCaching = hasTransformers && this.transformers.get(0) instanceof CachingResourceTransformer;
      result.add(hasCaching ? 1 : 0, new CssLinkResourceTransformer());
      return result;
   }
   return this.transformers;
}

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#mvcResourceUrlProvider

@Bean
   public ResourceUrlProvider mvcResourceUrlProvider() {
//    初始化资源url服务器
      ResourceUrlProvider urlProvider = new ResourceUrlProvider();
//    获取url路径解析器 -》
      UrlPathHelper pathHelper = getPathMatchConfigurer().getUrlPathHelper();
      if (pathHelper != null) {
         urlProvider.setUrlPathHelper(pathHelper);
      }
      PathMatcher pathMatcher = getPathMatchConfigurer().getPathMatcher();
      if (pathMatcher != null) {
         urlProvider.setPathMatcher(pathMatcher);
      }
      return urlProvider;
   }

进入到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#getPathMatchConfigurer

protected PathMatchConfigurer getPathMatchConfigurer() {
   if (this.pathMatchConfigurer == null) {
      this.pathMatchConfigurer = new PathMatchConfigurer();
      configurePathMatch(this.pathMatchConfigurer);
   }
   return this.pathMatchConfigurer;
}

这里前面介绍过了。

往上返回到这个方法org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport#resourceHandlerMapping

说到最后

本次源码解析仅表明我的观点，仅供参考。