@Override
	public void afterPropertiesSet() {
		// Do this first, it may add ResponseBody advice beans
		initControllerAdviceCache();

       // 省略掉無(wú)關(guān)代碼 
		// ...
	}

	private void initControllerAdviceCache() {
		if (getApplicationContext() == null) {
			return;
		}

       // 找到所有使用了注解 @ControllerAdvice 的bean組件 
		List<ControllerAdviceBean> adviceBeans = ControllerAdviceBean.findAnnotatedBeans(getApplicationContext());
        // 排序
		AnnotationAwareOrderComparator.sort(adviceBeans);


       // this. requestResponseBodyAdvice : 
       // 		用于記錄所有 @ControllerAdvice + RequestBodyAdvice/ResponseBodyAdvice bean 
       // this.modelAttributeAdviceCache : 
       // 		用于記錄所有 @ControllerAdvice bean組件中的 @ModuleAttribute 方法
       // this.initBinderAdviceCache : 
       // 	用于記錄所有 @ControllerAdvice bean組件中的 @InitBinder 方法
       // 用于臨時(shí)記錄所有 @ControllerAdvice + RequestResponseBodyAdvice bean
		List<Object> requestResponseBodyAdviceBeans = new ArrayList<>();

       // 遍歷每個(gè)使用了注解 @ControllerAdvice 的 bean 組件
		for (ControllerAdviceBean adviceBean : adviceBeans) {
			Class<?> beanType = adviceBean.getBeanType();
			if (beanType == null) {
				throw new IllegalStateException("Unresolvable type for ControllerAdviceBean: " + adviceBean);
			}
           // 獲取當(dāng)前  ControllerAdviceBean 中所有使用了 @ModelAttribute 注解的方法
			Set<Method> attrMethods = MethodIntrospector.selectMethods(beanType, MODEL_ATTRIBUTE_METHODS);
			if (!attrMethods.isEmpty()) {
				this.modelAttributeAdviceCache.put(adviceBean, attrMethods);
			}
            
           // 獲取當(dāng)前 ControllerAdviceBean 中所有使用了 @InitMethod 注解的方法
			Set<Method> binderMethods = MethodIntrospector.selectMethods(beanType, INIT_BINDER_METHODS);
			if (!binderMethods.isEmpty()) {
				this.initBinderAdviceCache.put(adviceBean, binderMethods);
			}
           // 如果當(dāng)前 ControllerAdviceBean 繼承自 RequestBodyAdvice，將其登記到 requestResponseBodyAdviceBeans
			if (RequestBodyAdvice.class.isAssignableFrom(beanType)) {
				requestResponseBodyAdviceBeans.add(adviceBean);
			}
            
           // 如果當(dāng)前 ControllerAdviceBean 繼承自 ResponseBodyAdvice，將其登記到 requestResponseBodyAdviceBeans  
			if (ResponseBodyAdvice.class.isAssignableFrom(beanType)) {
				requestResponseBodyAdviceBeans.add(adviceBean);
			}
		}
        
		if (!requestResponseBodyAdviceBeans.isEmpty()) {
			this.requestResponseBodyAdvice.addAll(0, requestResponseBodyAdviceBeans);
		}

		if (logger.isDebugEnabled()) {
			int modelSize = this.modelAttributeAdviceCache.size();
			int binderSize = this.initBinderAdviceCache.size();
			int reqCount = getBodyAdviceCount(RequestBodyAdvice.class);
			int resCount = getBodyAdviceCount(ResponseBodyAdvice.class);
			if (modelSize == 0 && binderSize == 0 && reqCount == 0 && resCount == 0) {
				logger.debug("ControllerAdvice beans: none");
			}
			else {
				logger.debug("ControllerAdvice beans: " + modelSize + " @ModelAttribute, " + binderSize +
						" @InitBinder, " + reqCount + " RequestBodyAdvice, " + resCount + " ResponseBodyAdvice");
			}
		}
	}

	/**
	 * Return the list of argument resolvers to use including built-in resolvers
	 * and custom resolvers provided via {@link #setCustomArgumentResolvers}.
	 */
	private List<HandlerMethodArgumentResolver> getDefaultArgumentResolvers() {
		List<HandlerMethodArgumentResolver> resolvers = new ArrayList<>();

		// ... 省略無(wú)關(guān)代碼        
		resolvers.add(new RequestResponseBodyMethodProcessor(getMessageConverters(), 
			this.requestResponseBodyAdvice));
        // ... 省略無(wú)關(guān)代碼
		resolvers.add(new RequestPartMethodArgumentResolver(getMessageConverters(), 
			this.requestResponseBodyAdvice));		
        // ... 省略無(wú)關(guān)代碼
		resolvers.add(new HttpEntityMethodProcessor(getMessageConverters(), 
			this.requestResponseBodyAdvice));
		// ... 省略無(wú)關(guān)代碼

		return resolvers;
	}

	@Override
	public void afterPropertiesSet() {
		// Do this first, it may add ResponseBody advice beans
		initControllerAdviceCache();

		if (this.argumentResolvers == null) {
			List<HandlerMethodArgumentResolver> resolvers = getDefaultArgumentResolvers(); // <==
			this.argumentResolvers = new HandlerMethodArgumentResolverComposite()
											.addResolvers(resolvers);
		}
	
        // 省略無(wú)關(guān)代碼
	}

	private ModelFactory getModelFactory(HandlerMethod handlerMethod, WebDataBinderFactory binderFactory) {
		SessionAttributesHandler sessionAttrHandler = getSessionAttributesHandler(handlerMethod);
		Class<?> handlerType = handlerMethod.getBeanType();
		Set<Method> methods = this.modelAttributeCache.get(handlerType);
		if (methods == null) {
			// 獲取當(dāng)前控制器類中使用了 @ModelAttribute 的方法
			methods = MethodIntrospector.selectMethods(handlerType, MODEL_ATTRIBUTE_METHODS);
			this.modelAttributeCache.put(handlerType, methods);
		}
		List<InvocableHandlerMethod> attrMethods = new ArrayList<>();
		// Global methods first
		// 遍歷@ControllerAdvice bean中所有使用了 @ModelAttribute 的方法，
		// 將其包裝成 InvocableHandlerMethod 放到 attrMethods
		// ********* 這里就是 modelAttributeAdviceCache 被使用到的地方了 ************
		this.modelAttributeAdviceCache.forEach((clazz, methodSet) -> {
			if (clazz.isApplicableToBeanType(handlerType)) {
				Object bean = clazz.resolveBean();
				for (Method method : methodSet) {
					attrMethods.add(createModelAttributeMethod(binderFactory, bean, method));
				}
			}
		});
        
		// 遍歷當(dāng)前控制器類中中所有使用了 @ModelAttribute 的方法，
		// 也將其包裝成 InvocableHandlerMethod 放到 attrMethods        
		for (Method method : methods) {
			Object bean = handlerMethod.getBean();
			attrMethods.add(createModelAttributeMethod(binderFactory, bean, method));
		}
        
		// 此時(shí)  attrMethods 包含了兩類 InvocableHandlerMethod， 分別來(lái)自于 :
		// 1. @ControllerAdvice bean 中所有使用了 @ModelAttribute 的方法
		// 2. 當(dāng)前控制器類中中所有使用了 @ModelAttribute 的方法
		return new ModelFactory(attrMethods, binderFactory, sessionAttrHandler);
	}
	
   // 從指定 bean 的方法 method ，其實(shí)是一個(gè)使用了注解 @ModelAttribute 的方法，
   // 構(gòu)造一個(gè) InvocableHandlerMethod 對(duì)象
	private InvocableHandlerMethod createModelAttributeMethod(WebDataBinderFactory factory, 
			Object bean, Method method) {
		InvocableHandlerMethod attrMethod = new InvocableHandlerMethod(bean, method);
		if (this.argumentResolvers != null) {
			attrMethod.setHandlerMethodArgumentResolvers(this.argumentResolvers);
		}
		attrMethod.setParameterNameDiscoverer(this.parameterNameDiscoverer);
		attrMethod.setDataBinderFactory(factory);
		return attrMethod;
	}	

	@Nullable
	protected ModelAndView invokeHandlerMethod(HttpServletRequest request,
			HttpServletResponse response, HandlerMethod handlerMethod) throws Exception {

		ServletWebRequest webRequest = new ServletWebRequest(request, response);
		try {
          // 構(gòu)造調(diào)用 handlerMethod 所要使用的數(shù)據(jù)綁定器工廠  
			WebDataBinderFactory binderFactory = getDataBinderFactory(handlerMethod);
          // 構(gòu)造調(diào)用 handlerMethod 所要使用的數(shù)據(jù)模型工廠  
			ModelFactory modelFactory = getModelFactory(handlerMethod, binderFactory);
        // 省略無(wú)關(guān)代碼 ...            
  }

	private WebDataBinderFactory getDataBinderFactory(HandlerMethod handlerMethod) throws Exception {
		Class<?> handlerType = handlerMethod.getBeanType();
		Set<Method> methods = this.initBinderCache.get(handlerType);
		if (methods == null) {
          // 獲取當(dāng)前控制器類中使用了 @InitBinder 的方法  
			methods = MethodIntrospector.selectMethods(handlerType, INIT_BINDER_METHODS);
			this.initBinderCache.put(handlerType, methods);
		}
		List<InvocableHandlerMethod> initBinderMethods = new ArrayList<>();
		// Global methods first
		// 遍歷@ControllerAdvice bean中所有使用了 @InitBinder 的方法，
		// 將其包裝成 InvocableHandlerMethod 放到 initBinderMethods
		// ********* 這里就是 initBinderAdviceCache 被使用到的地方了 ************        
		this.initBinderAdviceCache.forEach((clazz, methodSet) -> {
			if (clazz.isApplicableToBeanType(handlerType)) {
				Object bean = clazz.resolveBean();
				for (Method method : methodSet) {
					initBinderMethods.add(createInitBinderMethod(bean, method));
				}
			}
		});
        
		// 遍歷當(dāng)前控制器類中所有使用了 @InitBinder 的方法，
		// 將其包裝成 InvocableHandlerMethod 放到 initBinderMethods        
		for (Method method : methods) {
			Object bean = handlerMethod.getBean();
			initBinderMethods.add(createInitBinderMethod(bean, method));
		}
        
		// 此時(shí)  initBinderMethods 包含了兩類 InvocableHandlerMethod， 分別來(lái)自于 :
		// 1. @ControllerAdvice bean 中所有使用了 @InitBinder 的方法
		// 2. 當(dāng)前控制器類中中所有使用了 @InitBinder 的方法        
		return createDataBinderFactory(initBinderMethods);
	}
    
   // 從指定 bean 的方法 method ，其實(shí)是一個(gè)使用了注解 @InitBinder 的方法，
   // 構(gòu)造一個(gè) InvocableHandlerMethod 對(duì)象
	private InvocableHandlerMethod createInitBinderMethod(Object bean, Method method) {
		InvocableHandlerMethod binderMethod = new InvocableHandlerMethod(bean, method);
		if (this.initBinderArgumentResolvers != null) {
			binderMethod.setHandlerMethodArgumentResolvers(this.initBinderArgumentResolvers);
		}
		binderMethod.setDataBinderFactory(new DefaultDataBinderFactory(this.webBindingInitializer));
		binderMethod.setParameterNameDiscoverer(this.parameterNameDiscoverer);
		return binderMethod;
	}

	/**
	 * Template method to create a new InitBinderDataBinderFactory instance.
	 * <p>The default implementation creates a ServletRequestDataBinderFactory.
	 * This can be overridden for custom ServletRequestDataBinder subclasses.
	 * @param binderMethods {@code @InitBinder} methods
	 * @return the InitBinderDataBinderFactory instance to use
	 * @throws Exception in case of invalid state or arguments
	 */
	protected InitBinderDataBinderFactory createDataBinderFactory(
											List<InvocableHandlerMethod> binderMethods)
			throws Exception {

		return new ServletRequestDataBinderFactory(binderMethods, getWebBindingInitializer());
	}

	@Nullable
	protected ModelAndView invokeHandlerMethod(HttpServletRequest request,
			HttpServletResponse response, HandlerMethod handlerMethod) throws Exception {

		ServletWebRequest webRequest = new ServletWebRequest(request, response);
		try {
          // 構(gòu)造調(diào)用 handlerMethod 所要使用的數(shù)據(jù)綁定器工廠  
			WebDataBinderFactory binderFactory = getDataBinderFactory(handlerMethod);
          // 構(gòu)造調(diào)用 handlerMethod 所要使用的數(shù)據(jù)模型工廠  
			ModelFactory modelFactory = getModelFactory(handlerMethod, binderFactory);
        // 省略無(wú)關(guān)代碼 ...            
  }