springmvc原始碼解析MvcNamespaceHandler之 <mvc:annotation-driven/>一
阿新 • • 發佈：2019-03-14
說在前面
本次主要介紹springmvc配置解析。
springmvc配置解析
本次介紹MvcNamespaceHandler。
public void init() {
registerBeanDefinitionParser("annotation-driven", new AnnotationDrivenBeanDefinitionParser());
registerBeanDefinitionParser("default-servlet-handler", new DefaultServletHandlerBeanDefinitionParser());
registerBeanDefinitionParser("interceptors", new InterceptorsBeanDefinitionParser());
registerBeanDefinitionParser("resources", new ResourcesBeanDefinitionParser());
registerBeanDefinitionParser("view-controller", new ViewControllerBeanDefinitionParser());
registerBeanDefinitionParser("redirect-view-controller", new ViewControllerBeanDefinitionParser());
registerBeanDefinitionParser("status-controller", new ViewControllerBeanDefinitionParser());
registerBeanDefinitionParser("view-resolvers", new ViewResolversBeanDefinitionParser());
registerBeanDefinitionParser("tiles-configurer", new TilesConfigurerBeanDefinitionParser());
registerBeanDefinitionParser("freemarker-configurer", new FreeMarkerConfigurerBeanDefinitionParser());
registerBeanDefinitionParser("velocity-configurer", new VelocityConfigurerBeanDefinitionParser());
registerBeanDefinitionParser("groovy-configurer", new GroovyMarkupConfigurerBeanDefinitionParser());
registerBeanDefinitionParser("script-template-configurer", new ScriptTemplateConfigurerBeanDefinitionParser());
registerBeanDefinitionParser("cors", new CorsBeanDefinitionParser());
}進入到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#parse
接下來介紹這個標籤<mvc:annotation-driven/>原始碼解析，找到這個類org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser，這個標籤做了什麼事情呢。
預設註冊了RequestMappingHandlerMapping、BeanNameUrlHandlerMapping、RequestMappingHandlerAdapter、HttpRequestHandlerAdapter、SimpleControllerHandlerAdapter、ExceptionHandlerExceptionResolver、ResponseStatusExceptionResolver、DefaultHandlerExceptionResolver這些元件，這些元件是幹什麼的第一篇文章有介紹。
找到這個org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#parse，由於之前spring原始碼解析的鋪墊，我們知道解析xml標籤bean定義到beanFactory會執行這個方法。載入xml解析bean定義註冊到beanFactory這裡不做詳細介紹，大家可以詳約之前的spring原始碼解析文章。
@Override
public BeanDefinition parse(Element element, ParserContext context) {
Object source = context.extractSource(element);
// 獲取XmlReaderContext
XmlReaderContext readerContext = context.getReaderContext();
CompositeComponentDefinition compDefinition = new CompositeComponentDefinition(element.getTagName(), source);
context.pushContainingComponent(compDefinition);
// 請求、響應格式管理器 ->
RuntimeBeanReference contentNegotiationManager = getContentNegotiationManager(element, source, context);
// 註冊RequestMappingHandlerMapping bean定義
RootBeanDefinition handlerMappingDef = new RootBeanDefinition(RequestMappingHandlerMapping.class);
handlerMappingDef.setSource(source);
handlerMappingDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
// 設定順序，預設是0
handlerMappingDef.getPropertyValues().add("order", 0);
// 新增依賴bean定義
handlerMappingDef.getPropertyValues().add("contentNegotiationManager", contentNegotiationManager);
// 是否開啟矩陣變數查詢
if (element.hasAttribute("enable-matrix-variables")) {
Boolean enableMatrixVariables = Boolean.valueOf(element.getAttribute("enable-matrix-variables"));
handlerMappingDef.getPropertyValues().add("removeSemicolonContent", !enableMatrixVariables);
}
else if (element.hasAttribute("enableMatrixVariables")) {
Boolean enableMatrixVariables = Boolean.valueOf(element.getAttribute("enableMatrixVariables"));
handlerMappingDef.getPropertyValues().add("removeSemicolonContent", !enableMatrixVariables);
}
// ->
configurePathMatchingProperties(handlerMappingDef, element, context);
// 註冊RequestMappingHandlerMapping bean定義
readerContext.getRegistry().registerBeanDefinition(HANDLER_MAPPING_BEAN_NAME , handlerMappingDef);
// 註冊跨域支援bean定義 ->
RuntimeBeanReference corsRef = MvcNamespaceUtils.registerCorsConfigurations(null, context, source);
handlerMappingDef.getPropertyValues().add("corsConfigurations", corsRef);
// 型別轉換服務bean定義解析
RuntimeBeanReference conversionService = getConversionService(element, source, context);
// validator bean定義解析 ->
RuntimeBeanReference validator = getValidator(element, source, context);
// 解析訊息編碼解析器bean定義 ->
RuntimeBeanReference messageCodesResolver = getMessageCodesResolver(element);
RootBeanDefinition bindingDef = new RootBeanDefinition(ConfigurableWebBindingInitializer.class);
bindingDef.setSource(source);
bindingDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
bindingDef.getPropertyValues().add("conversionService", conversionService);
bindingDef.getPropertyValues().add("validator", validator);
bindingDef.getPropertyValues().add("messageCodesResolver", messageCodesResolver);
// 獲取訊息轉換器 ->
ManagedList<?> messageConverters = getMessageConverters(element, source, context);
// 獲取引數解析器 ->
ManagedList<?> argumentResolvers = getArgumentResolvers(element, context);
// 獲取返回值handler ->
ManagedList<?> returnValueHandlers = getReturnValueHandlers(element, context);
// 獲取非同步超時時間 ->
String asyncTimeout = getAsyncTimeout(element);
// 獲取非同步任務執行器 ->
RuntimeBeanReference asyncExecutor = getAsyncExecutor(element);
// 獲取有返回值的攔截器
ManagedList<?> callableInterceptors = getCallableInterceptors(element, source, context);
// 獲取延遲結果攔截器 ->
ManagedList<?> deferredResultInterceptors = getDeferredResultInterceptors(element, source, context);
// 註冊RequestMappingHandlerAdapter bean定義
RootBeanDefinition handlerAdapterDef = new RootBeanDefinition(RequestMappingHandlerAdapter.class);
handlerAdapterDef.setSource(source);
handlerAdapterDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
handlerAdapterDef.getPropertyValues().add("contentNegotiationManager", contentNegotiationManager);
handlerAdapterDef.getPropertyValues().add("webBindingInitializer", bindingDef);
handlerAdapterDef.getPropertyValues().add("messageConverters", messageConverters);
// 新增json請求通知處理器JsonViewRequestBodyAdvice ->
addRequestBodyAdvice(handlerAdapterDef);
// 新增json響應通知處理器JsonViewResponseBodyAdvice ->
addResponseBodyAdvice(handlerAdapterDef);
// 重定向操作是否預設不帶引數
if (element.hasAttribute("ignore-default-model-on-redirect")) {
Boolean ignoreDefaultModel = Boolean.valueOf(element.getAttribute("ignore-default-model-on-redirect"));
handlerAdapterDef.getPropertyValues().add("ignoreDefaultModelOnRedirect", ignoreDefaultModel);
}
else if (element.hasAttribute("ignoreDefaultModelOnRedirect")) {
// "ignoreDefaultModelOnRedirect" spelling is deprecated
Boolean ignoreDefaultModel = Boolean.valueOf(element.getAttribute("ignoreDefaultModelOnRedirect"));
handlerAdapterDef.getPropertyValues().add("ignoreDefaultModelOnRedirect", ignoreDefaultModel);
}
if (argumentResolvers != null) {
handlerAdapterDef.getPropertyValues().add("customArgumentResolvers", argumentResolvers);
}
if (returnValueHandlers != null) {
handlerAdapterDef.getPropertyValues().add("customReturnValueHandlers", returnValueHandlers);
}
if (asyncTimeout != null) {
// 解析非同步請求超時時間
handlerAdapterDef.getPropertyValues().add("asyncRequestTimeout", asyncTimeout);
}
if (asyncExecutor != null) {
// 註冊非同步執行緒池
handlerAdapterDef.getPropertyValues().add("taskExecutor", asyncExecutor);
}
handlerAdapterDef.getPropertyValues().add("callableInterceptors", callableInterceptors);
handlerAdapterDef.getPropertyValues().add("deferredResultInterceptors", deferredResultInterceptors);
readerContext.getRegistry().registerBeanDefinition(HANDLER_ADAPTER_BEAN_NAME , handlerAdapterDef);
RootBeanDefinition uriContributorDef =
new RootBeanDefinition(CompositeUriComponentsContributorFactoryBean.class);
uriContributorDef.setSource(source);
uriContributorDef.getPropertyValues().addPropertyValue("handlerAdapter", handlerAdapterDef);
uriContributorDef.getPropertyValues().addPropertyValue("conversionService", conversionService);
String uriContributorName = MvcUriComponentsBuilder.MVC_URI_COMPONENTS_CONTRIBUTOR_BEAN_NAME;
readerContext.getRegistry().registerBeanDefinition(uriContributorName, uriContributorDef);
// 註冊轉換服務攔截器
RootBeanDefinition csInterceptorDef = new RootBeanDefinition(ConversionServiceExposingInterceptor.class);
csInterceptorDef.setSource(source);
csInterceptorDef.getConstructorArgumentValues().addIndexedArgumentValue(0, conversionService);
RootBeanDefinition mappedInterceptorDef = new RootBeanDefinition(MappedInterceptor.class);
mappedInterceptorDef.setSource(source);
mappedInterceptorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
mappedInterceptorDef.getConstructorArgumentValues().addIndexedArgumentValue(0, (Object) null);
mappedInterceptorDef.getConstructorArgumentValues().addIndexedArgumentValue(1, csInterceptorDef);
String mappedInterceptorName = readerContext.registerWithGeneratedName(mappedInterceptorDef);
// 註冊異常請求解析器bean定義
RootBeanDefinition methodExceptionResolver = new RootBeanDefinition(ExceptionHandlerExceptionResolver.class);
methodExceptionResolver.setSource(source);
methodExceptionResolver.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
methodExceptionResolver.getPropertyValues().add("contentNegotiationManager", contentNegotiationManager);
methodExceptionResolver.getPropertyValues().add("messageConverters", messageConverters);
methodExceptionResolver.getPropertyValues().add("order", 0);
// 新增json響應通知處理器JsonViewResponseBodyAdvice
addResponseBodyAdvice(methodExceptionResolver);
if (argumentResolvers != null) {
methodExceptionResolver.getPropertyValues().add("customArgumentResolvers", argumentResolvers);
}
if (returnValueHandlers != null) {
methodExceptionResolver.getPropertyValues().add("customReturnValueHandlers", returnValueHandlers);
}
String methodExResolverName = readerContext.registerWithGeneratedName(methodExceptionResolver);
// 註冊響應狀態碼異常解析器bean定義
RootBeanDefinition statusExceptionResolver = new RootBeanDefinition(ResponseStatusExceptionResolver.class);
statusExceptionResolver.setSource(source);
statusExceptionResolver.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
statusExceptionResolver.getPropertyValues().add("order", 1);
String statusExResolverName = readerContext.registerWithGeneratedName(statusExceptionResolver);
// 註冊預設異常處理器bean定義
RootBeanDefinition defaultExceptionResolver = new RootBeanDefinition(DefaultHandlerExceptionResolver.class);
defaultExceptionResolver.setSource(source);
defaultExceptionResolver.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
defaultExceptionResolver.getPropertyValues().add("order", 2);
String defaultExResolverName = readerContext.registerWithGeneratedName(defaultExceptionResolver);
context.registerComponent(new BeanComponentDefinition(handlerMappingDef, HANDLER_MAPPING_BEAN_NAME));
context.registerComponent(new BeanComponentDefinition(handlerAdapterDef, HANDLER_ADAPTER_BEAN_NAME));
context.registerComponent(new BeanComponentDefinition(uriContributorDef, uriContributorName));
context.registerComponent(new BeanComponentDefinition(mappedInterceptorDef, mappedInterceptorName));
context.registerComponent(new BeanComponentDefinition(methodExceptionResolver, methodExResolverName));
context.registerComponent(new BeanComponentDefinition(statusExceptionResolver, statusExResolverName));
context.registerComponent(new BeanComponentDefinition(defaultExceptionResolver, defaultExResolverName));
// Ensure BeanNameUrlHandlerMapping (SPR-8289) and default HandlerAdapters are not "turned off" 註冊預設bean定義元件 ->
MvcNamespaceUtils.registerDefaultComponents(context, source);
context.popAndRegisterContainingComponent();
return null;
}進入到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#getContentNegotiationManager
private RuntimeBeanReference getContentNegotiationManager(Element element, Object source, ParserContext context) {
RuntimeBeanReference beanRef;
// content-negotiation-manager 標籤屬性
if (element.hasAttribute("content-negotiation-manager")) {
String name = element.getAttribute("content-negotiation-manager");
beanRef = new RuntimeBeanReference(name);
}
else {
RootBeanDefinition factoryBeanDef = new RootBeanDefinition(ContentNegotiationManagerFactoryBean.class);
factoryBeanDef.setSource(source);
factoryBeanDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
// 新增預設的mediaTypes ->
factoryBeanDef.getPropertyValues().add("mediaTypes", getDefaultMediaTypes());
String name = CONTENT_NEGOTIATION_MANAGER_BEAN_NAME;
// 註冊mvcContentNegotiationManager bean定義
context.getReaderContext().getRegistry().registerBeanDefinition(name , factoryBeanDef);
// 祖冊元件
context.registerComponent(new BeanComponentDefinition(factoryBeanDef, name));
beanRef = new RuntimeBeanReference(name);
}
return beanRef;
}
進入到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#getDefaultMediaTypes
private Properties getDefaultMediaTypes() {
Properties defaultMediaTypes = new Properties();
if (romePresent) {
defaultMediaTypes.put("atom", MediaType.APPLICATION_ATOM_XML_VALUE);
defaultMediaTypes.put("rss", MediaType.APPLICATION_RSS_XML_VALUE);
}
// xml型別 jaxb jackson
if (jaxb2Present || jackson2XmlPresent) {
defaultMediaTypes.put("xml", MediaType.APPLICATION_XML_VALUE);
}
// json型別 jackson gson
if (jackson2Present || gsonPresent) {
defaultMediaTypes.put("json", MediaType.APPLICATION_JSON_VALUE);
}
return defaultMediaTypes;
}
往上返回到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#configurePathMatchingProperties
private void configurePathMatchingProperties(
RootBeanDefinition handlerMappingDef, Element element, ParserContext context) {
// 路徑規則檔案配置
Element pathMatchingElement = DomUtils.getChildElementByTagName(element, "path-matching");
if (pathMatchingElement != null) {
Object source = context.extractSource(element);
// 字尾
if (pathMatchingElement.hasAttribute("suffix-pattern")) {
Boolean useSuffixPatternMatch = Boolean.valueOf(pathMatchingElement.getAttribute("suffix-pattern"));
handlerMappingDef.getPropertyValues().add("useSuffixPatternMatch", useSuffixPatternMatch);
}
// 是否支援混合檢視
if (pathMatchingElement.hasAttribute("trailing-slash")) {
Boolean useTrailingSlashMatch = Boolean.valueOf(pathMatchingElement.getAttribute("trailing-slash"));
handlerMappingDef.getPropertyValues().add("useTrailingSlashMatch", useTrailingSlashMatch);
}
// 是否只註冊字首
if (pathMatchingElement.hasAttribute("registered-suffixes-only")) {
Boolean useRegisteredSuffixPatternMatch = Boolean.valueOf(pathMatchingElement.getAttribute("registered-suffixes-only"));
handlerMappingDef.getPropertyValues().add("useRegisteredSuffixPatternMatch", useRegisteredSuffixPatternMatch);
}
// 註冊path解析類
RuntimeBeanReference pathHelperRef = null;
if (pathMatchingElement.hasAttribute("path-helper")) {
pathHelperRef = new RuntimeBeanReference(pathMatchingElement.getAttribute("path-helper"));
}
// ->
pathHelperRef = MvcNamespaceUtils.registerUrlPathHelper(pathHelperRef, context, source);
handlerMappingDef.getPropertyValues().add("urlPathHelper", pathHelperRef);
RuntimeBeanReference pathMatcherRef = null;
// 註冊路徑匹配器
if (pathMatchingElement.hasAttribute("path-matcher")) {
pathMatcherRef = new RuntimeBeanReference(pathMatchingElement.getAttribute("path-matcher"));
}
// ->
pathMatcherRef = MvcNamespaceUtils.registerPathMatcher(pathMatcherRef, context, source);
handlerMappingDef.getPropertyValues().add("pathMatcher", pathMatcherRef);
}
}
進入到這個方法org.springframework.web.servlet.config.MvcNamespaceUtils#registerUrlPathHelper
public static RuntimeBeanReference registerUrlPathHelper(
RuntimeBeanReference urlPathHelperRef, ParserContext parserContext, Object source) {
if (urlPathHelperRef != null) {
if (parserContext.getRegistry().isAlias(URL_PATH_HELPER_BEAN_NAME)) {
parserContext.getRegistry().removeAlias(URL_PATH_HELPER_BEAN_NAME);
}
// 註冊mvcUrlPathHelper別名
parserContext.getRegistry().registerAlias(urlPathHelperRef.getBeanName(), URL_PATH_HELPER_BEAN_NAME);
}
else if (!parserContext.getRegistry().isAlias(URL_PATH_HELPER_BEAN_NAME)
&& !parserContext.getRegistry().containsBeanDefinition(URL_PATH_HELPER_BEAN_NAME)) {
RootBeanDefinition urlPathHelperDef = new RootBeanDefinition(UrlPathHelper.class);
urlPathHelperDef.setSource(source);
urlPathHelperDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
// 註冊mvcUrlPathHelper bean定義
parserContext.getRegistry().registerBeanDefinition(URL_PATH_HELPER_BEAN_NAME, urlPathHelperDef);
parserContext.registerComponent(new BeanComponentDefinition(urlPathHelperDef, URL_PATH_HELPER_BEAN_NAME));
}
return new RuntimeBeanReference(URL_PATH_HELPER_BEAN_NAME);
}
往上返回到這個方法org.springframework.web.servlet.config.MvcNamespaceUtils#registerPathMatcher
public static RuntimeBeanReference registerPathMatcher(
RuntimeBeanReference pathMatcherRef, ParserContext parserContext, Object source) {
if (pathMatcherRef != null) {
if (parserContext.getRegistry().isAlias(PATH_MATCHER_BEAN_NAME)) {
parserContext.getRegistry().removeAlias(PATH_MATCHER_BEAN_NAME);
}
// 註冊別名mvcPathMatcher
parserContext.getRegistry().registerAlias(pathMatcherRef.getBeanName(), PATH_MATCHER_BEAN_NAME);
}
else if (!parserContext.getRegistry().isAlias(PATH_MATCHER_BEAN_NAME)
&& !parserContext.getRegistry().containsBeanDefinition(PATH_MATCHER_BEAN_NAME)) {
RootBeanDefinition pathMatcherDef = new RootBeanDefinition(AntPathMatcher.class);
pathMatcherDef.setSource(source);
pathMatcherDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
// 註冊mvcPathMatcher bean定義
parserContext.getRegistry().registerBeanDefinition(PATH_MATCHER_BEAN_NAME, pathMatcherDef);
parserContext.registerComponent(new BeanComponentDefinition(pathMatcherDef, PATH_MATCHER_BEAN_NAME));
}
return new RuntimeBeanReference(PATH_MATCHER_BEAN_NAME);
}
往上返回到這個方法org.springframework.web.servlet.config.MvcNamespaceUtils#registerCorsConfigurations
public static RuntimeBeanReference registerCorsConfigurations(
Map<String, CorsConfiguration> corsConfigurations, ParserContext context, Object source) {
// mvcCorsConfigurations 跨域支援bean定義解析
if (!context.getRegistry().containsBeanDefinition(CORS_CONFIGURATION_BEAN_NAME)) {
RootBeanDefinition corsDef = new RootBeanDefinition(LinkedHashMap.class);
corsDef.setSource(source);
corsDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
if (corsConfigurations != null) {
corsDef.getConstructorArgumentValues().addIndexedArgumentValue(0, corsConfigurations);
}
// 註冊mvcCorsConfigurations bean定義
context.getReaderContext().getRegistry().registerBeanDefinition(CORS_CONFIGURATION_BEAN_NAME, corsDef);
context.registerComponent(new BeanComponentDefinition(corsDef, CORS_CONFIGURATION_BEAN_NAME));
}
else if (corsConfigurations != null) {
BeanDefinition corsDef = context.getRegistry().getBeanDefinition(CORS_CONFIGURATION_BEAN_NAME);
corsDef.getConstructorArgumentValues().addIndexedArgumentValue(0, corsConfigurations);
}
return new RuntimeBeanReference(CORS_CONFIGURATION_BEAN_NAME);
}
往上返回到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#getValidator
private RuntimeBeanReference getValidator(Element element, Object source, ParserContext context) {
// 解析validator屬性值，註冊驗證服務
if (element.hasAttribute("validator")) {
return new RuntimeBeanReference(element.getAttribute("validator"));
}
else if (javaxValidationPresent) {
RootBeanDefinition validatorDef = new RootBeanDefinition(
"org.springframework.validation.beanvalidation.OptionalValidatorFactoryBean");
validatorDef.setSource(source);
validatorDef.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
String validatorName = context.getReaderContext().registerWithGeneratedName(validatorDef);
context.registerComponent(new BeanComponentDefinition(validatorDef, validatorName));
return new RuntimeBeanReference(validatorName);
}
else {
return null;
}
}
往上返回到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#getMessageCodesResolver
private RuntimeBeanReference getMessageCodesResolver(Element element) {
if (element.hasAttribute("message-codes-resolver")) {
return new RuntimeBeanReference(element.getAttribute("message-codes-resolver"));
}
else {
return null;
}
}
往上返回到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#getMessageConverters
private ManagedList<?> getMessageConverters(Element element, Object source, ParserContext context) {
Element convertersElement = DomUtils.getChildElementByTagName(element, "message-converters");
ManagedList<Object> messageConverters = new ManagedList<Object>();
if (convertersElement != null) {
messageConverters.setSource(source);
for (Element beanElement : DomUtils.getChildElementsByTagName(convertersElement, "bean", "ref")) {
Object object = context.getDelegate().parsePropertySubElement(beanElement, null);
messageConverters.add(object);
}
}
// 是否註冊預設值ByteArrayHttpMessageConverter
if (convertersElement == null || Boolean.valueOf(convertersElement.getAttribute("register-defaults"))) {
messageConverters.setSource(source);
messageConverters.add(createConverterDefinition(ByteArrayHttpMessageConverter.class, source));
// 註冊StringHttpMessageConverter bean定義
RootBeanDefinition stringConverterDef = createConverterDefinition(StringHttpMessageConverter.class, source);
stringConverterDef.getPropertyValues().add("writeAcceptCharset", false);
messageConverters.add(stringConverterDef);
// 新增預設轉換器
messageConverters.add(createConverterDefinition(ResourceHttpMessageConverter.class, source));
messageConverters.add(createConverterDefinition(SourceHttpMessageConverter.class, source));
// ->
messageConverters.add(createConverterDefinition(AllEncompassingFormHttpMessageConverter.class, source));
if (romePresent) {
messageConverters.add(createConverterDefinition(AtomFeedHttpMessageConverter.class, source));
messageConverters.add(createConverterDefinition(RssChannelHttpMessageConverter.class, source));
}
// 新增json轉xml轉換器
if (jackson2XmlPresent) {
Class<?> type = MappingJackson2XmlHttpMessageConverter.class;
RootBeanDefinition jacksonConverterDef = createConverterDefinition(type, source);
GenericBeanDefinition jacksonFactoryDef = createObjectMapperFactoryDefinition(source);
jacksonFactoryDef.getPropertyValues().add("createXmlMapper", true);
jacksonConverterDef.getConstructorArgumentValues().addIndexedArgumentValue(0, jacksonFactoryDef);
messageConverters.add(jacksonConverterDef);
}
// 新增物件xml轉換器
else if (jaxb2Present) {
messageConverters.add(createConverterDefinition(Jaxb2RootElementHttpMessageConverter.class, source));
}
// 新增Jackson json轉換器
if (jackson2Present) {
Class<?> type = MappingJackson2HttpMessageConverter.class;
RootBeanDefinition jacksonConverterDef = createConverterDefinition(type, source);
GenericBeanDefinition jacksonFactoryDef = createObjectMapperFactoryDefinition(source);
jacksonConverterDef.getConstructorArgumentValues().addIndexedArgumentValue(0, jacksonFactoryDef);
messageConverters.add(jacksonConverterDef);
}
// 新增Gson json轉換器
else if (gsonPresent) {
messageConverters.add(createConverterDefinition(GsonHttpMessageConverter.class, source));
}
}
return messageConverters;
}
進入到這個方法org.springframework.http.converter.support.AllEncompassingFormHttpMessageConverter#AllEncompassingFormHttpMessageConverter
public AllEncompassingFormHttpMessageConverter() {
// 新增預設xml和json真支援轉換器
addPartConverter(new SourceHttpMessageConverter<Source>());
if (jaxb2Present && !jackson2XmlPresent) {
addPartConverter(new Jaxb2RootElementHttpMessageConverter());
}
if (jackson2Present) {
addPartConverter(new MappingJackson2HttpMessageConverter());
}
else if (gsonPresent) {
addPartConverter(new GsonHttpMessageConverter());
}
if (jackson2XmlPresent) {
addPartConverter(new MappingJackson2XmlHttpMessageConverter());
}
}
往上返回到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#getArgumentResolvers
private ManagedList<?> getArgumentResolvers(Element element, ParserContext context) {
Element resolversElement = DomUtils.getChildElementByTagName(element, "argument-resolvers");
if (resolversElement != null) {
ManagedList<Object> resolvers = extractBeanSubElements(resolversElement, context);
// ->
return wrapLegacyResolvers(resolvers, context);
}
return null;
}
進入到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#wrapLegacyResolvers
private ManagedList<Object> wrapLegacyResolvers(List<Object> list, ParserContext context) {
ManagedList<Object> result = new ManagedList<Object>();
for (Object object : list) {
if (object instanceof BeanDefinitionHolder) {
BeanDefinitionHolder beanDef = (BeanDefinitionHolder) object;
String className = beanDef.getBeanDefinition().getBeanClassName();
Class<?> clazz = ClassUtils.resolveClassName(className, context.getReaderContext().getBeanClassLoader());
if (WebArgumentResolver.class.isAssignableFrom(clazz)) {
// 新增ServletWebArgumentResolverAdapter 引數解析器介面卡
RootBeanDefinition adapter = new RootBeanDefinition(ServletWebArgumentResolverAdapter.class);
adapter.getConstructorArgumentValues().addIndexedArgumentValue(0, beanDef);
result.add(new BeanDefinitionHolder(adapter, beanDef.getBeanName() + "Adapter"));
continue;
}
}
result.add(object);
}
return result;
}
返回到這個方法org.springframework.web.servlet.config.AnnotationDrivenBeanDefinitionParser#parse這一行
// 獲取返回值handler ->
ManagedList<?> returnValueHandlers = getReturnValueHandlers(element, context);
下次繼續
說到最後
本次原始碼解析僅代表個人觀點，僅供參