1、說在前面的話

①、在說springmvc之前先說一下與之相關的一些類與介面：ContextLoaderListener與ServletContextListener，ContextLoaderListener實現了ServletContextListener介面。

ContextLoaderListener類：
啟動容器時候，自動裝配ApplicationContext的配置資訊。因為實現了ServletContextListener介面

在web.xml檔案中配置這個監聽器，啟動容器的時候就會預設執行它實現的方法。

ServletContextListener的核心邏輯就是初始化WebApplicationContext例項並存放在ServletContext中。

系統啟動的時候會執行ServletContextListener的contextInitialized()方法。

/**
 * Initialize the root web application context.
 */
@Override
public void contextInitialized(ServletContextEvent event) {
	initWebApplicationContext(event.getServletContext());
}

public WebApplicationContext initWebApplicationContext(ServletContext servletContext) {
    // WebApplicationContext存在性驗證
	if (servletContext.getAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE) != null) {
		throw new IllegalStateException(
				"Cannot initialize context because there is already a root application context present - " +
				"check whether you have multiple ContextLoader* definitions in your web.xml!");
	}

	Log logger = LogFactory.getLog(ContextLoader.class);
	servletContext.log("Initializing Spring root WebApplicationContext");
	if (logger.isInfoEnabled()) {
		logger.info("Root WebApplicationContext: initialization started");
	}
	long startTime = System.currentTimeMillis();

	try {
		// Store context in local instance variable, to guarantee that
		// it is available on ServletContext shutdown.
		if (this.context == null) {
            // 建立WebApplicationContext
			this.context = createWebApplicationContext(servletContext);
		}
		if (this.context instanceof ConfigurableWebApplicationContext) {
			ConfigurableWebApplicationContext cwac = (ConfigurableWebApplicationContext) this.context;
			if (!cwac.isActive()) {
				// The context has not yet been refreshed -> provide services such as
				// setting the parent context, setting the application context id, etc
				if (cwac.getParent() == null) {
					// The context instance was injected without an explicit parent ->
					// determine parent for root web application context, if any.
					ApplicationContext parent = loadParentContext(servletContext);
					cwac.setParent(parent);
				}
				configureAndRefreshWebApplicationContext(cwac, servletContext);
			}
		}
        // 將生成的WebApplicationContext儲存在servletContext中
		servletContext.setAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE, this.context);

		ClassLoader ccl = Thread.currentThread().getContextClassLoader();
		if (ccl == ContextLoader.class.getClassLoader()) {
			currentContext = this.context;
		}
		else if (ccl != null) {
            // 將WebApplicationContext和當前類載入器都加入到currentContextPerThread中
            // currentContextPerThread是一個ConcurrentHashMap
			currentContextPerThread.put(ccl, this.context);
		}

		if (logger.isDebugEnabled()) {
			logger.debug("Published root WebApplicationContext as ServletContext attribute with name [" +
					WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE + "]");
		}
		if (logger.isInfoEnabled()) {
			long elapsedTime = System.currentTimeMillis() - startTime;
			logger.info("Root WebApplicationContext: initialization completed in " + elapsedTime + " ms");
		}

		return this.context;
	}
	catch (RuntimeException ex) {
		logger.error("Context initialization failed", ex);
		servletContext.setAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE, ex);
		throw ex;
	}
	catch (Error err) {
		logger.error("Context initialization failed", err);
		servletContext.setAttribute(WebApplicationContext.ROOT_WEB_APPLICATION_CONTEXT_ATTRIBUTE, err);
		throw err;
	}
}
 

②、現在看下createWebApplicationContext(servletContext)的執行邏輯：

以下程式碼在ContextLoader類中，該類中有如下靜態程式碼塊會先執行:

static {
	// Load default strategy implementations from properties file.
	// This is currently strictly internal and not meant to be customized
	// by application developers.
	try {
        // DEFAULT_STRATEGIES_PATH = "ContextLoader.properties"
        // ContextLoader.properties與ContextLoader類在同級目錄
		ClassPathResource resource = new ClassPathResource(DEFAULT_STRATEGIES_PATH, ContextLoader.class);
		defaultStrategies = PropertiesLoaderUtils.loadProperties(resource);
	}
	catch (IOException ex) {
		throw new IllegalStateException("Could not load 'ContextLoader.properties': " + ex.getMessage());
	}
}
 

protected WebApplicationContext createWebApplicationContext(ServletContext sc) {
    // 該方法決定用什麼WebApplicationContext
	Class<?> contextClass = determineContextClass(sc);
	if (!ConfigurableWebApplicationContext.class.isAssignableFrom(contextClass)) {
		throw new ApplicationContextException("Custom context class [" + contextClass.getName() +
				"] is not of type [" + ConfigurableWebApplicationContext.class.getName() + "]");
	}
    // 使用反射建立例項
	return (ConfigurableWebApplicationContext) BeanUtils.instantiateClass(contextClass);
}

protected Class<?> determineContextClass(ServletContext servletContext) {
    // CONTEXT_CLASS_PARAM = "contextClass"
    // 先從servletContext查詢是否有了WebApplicationContext
	String contextClassName = servletContext.getInitParameter(CONTEXT_CLASS_PARAM);
	if (contextClassName != null) {
		try {
			return ClassUtils.forName(contextClassName, ClassUtils.getDefaultClassLoader());
		}
		catch (ClassNotFoundException ex) {
			throw new ApplicationContextException(
					"Failed to load custom context class [" + contextClassName + "]", ex);
		}
	}
	else {
        // 若沒有，就是用ContextLoader.properties檔案中的XmlWebApplicationContext
		contextClassName = defaultStrategies.getProperty(WebApplicationContext.class.getName());
		try {
			return ClassUtils.forName(contextClassName, ContextLoader.class.getClassLoader());
		}
		catch (ClassNotFoundException ex) {
			throw new ApplicationContextException(
					"Failed to load default context class [" + contextClassName + "]", ex);
		}
	}
}

2.SpringMVC的核心邏輯

①、DispatcherServlet是springmvc的核心類，也是實現核心邏輯的類。接下來是對DispatcherServlet進行分析：

由於DispatcherServlet是Servlet，所以檢視原始碼，看看是否實現了Servlet的方法，首先看init()方法，在HttpServletBean中找到了init()方法：

	/**
	 * Map config parameters onto bean properties of this servlet, and
	 * invoke subclass initialization.
	 * @throws ServletException if bean properties are invalid (or required
	 * properties are missing), or if subclass initialization fails.
	 */
	@Override
	public final void init() throws ServletException {
		if (logger.isDebugEnabled()) {
			logger.debug("Initializing servlet '" + getServletName() + "'");
		}

		// Set bean properties from init parameters.
         // 這裡主要是解析web.xml檔案中配置的init-param的值，並封裝到pvs中
		PropertyValues pvs = new ServletConfigPropertyValues(getServletConfig(), this.requiredProperties);
		if (!pvs.isEmpty()) {
			try {
                // 將當前servlet類轉換成BeanWrapper，從而可以使用spring方式對init-param的值進行注入
				BeanWrapper bw = PropertyAccessorFactory.forBeanPropertyAccess(this);
				ResourceLoader resourceLoader = new ServletContextResourceLoader(getServletContext());
				bw.registerCustomEditor(Resource.class, new ResourceEditor(resourceLoader, getEnvironment()));
                // 模板方法，留給子類覆蓋
				initBeanWrapper(bw);
                // 屬性注入
				bw.setPropertyValues(pvs, true);
			}
			catch (BeansException ex) {
				if (logger.isErrorEnabled()) {
					logger.error("Failed to set bean properties on servlet '" + getServletName() + "'", ex);
				}
				throw ex;
			}
		}

		// Let subclasses do whatever initialization they like.
         // 模板方法，留給子類拓展覆蓋，在子類FrameworkServlet中重寫了此方法
		initServletBean();

		if (logger.isDebugEnabled()) {
			logger.debug("Servlet '" + getServletName() + "' configured successfully");
		}
	}

②、在子類FrameworkServlet中重寫initServletBean()的方法：

    @Override
	protected final void initServletBean() throws ServletException {
		getServletContext().log("Initializing Spring FrameworkServlet '" + getServletName() + "'");
		if (this.logger.isInfoEnabled()) {
			this.logger.info("FrameworkServlet '" + getServletName() + "': initialization started");
		}
		long startTime = System.currentTimeMillis();

		try {
             // 建立或重新整理WebApplicationContext例項並對Servlet功能所使用的變數進行初始化
			this.webApplicationContext = initWebApplicationContext();
			initFrameworkServlet();
		}
		catch (ServletException ex) {
			this.logger.error("Context initialization failed", ex);
			throw ex;
		}
		catch (RuntimeException ex) {
			this.logger.error("Context initialization failed", ex);
			throw ex;
		}

		if (this.logger.isInfoEnabled()) {
			long elapsedTime = System.currentTimeMillis() - startTime;
			this.logger.info("FrameworkServlet '" + getServletName() + "': initialization completed in " +
					elapsedTime + " ms");
		}
	}

③、在FrameworkServlet中的initWebApplicationContext()方法：

protected WebApplicationContext initWebApplicationContext() {
		WebApplicationContext rootContext =
				WebApplicationContextUtils.getWebApplicationContext(getServletContext());
		WebApplicationContext wac = null;
		// this.webApplicationContext != null表示通過建構函式初始化webApplicationContext的
		if (this.webApplicationContext != null) {
			// A context instance was injected at construction time -> use it
			wac = this.webApplicationContext;
			if (wac instanceof ConfigurableWebApplicationContext) {
				ConfigurableWebApplicationContext cwac = (ConfigurableWebApplicationContext) wac;
				if (!cwac.isActive()) {
					// The context has not yet been refreshed -> provide services such as
					// setting the parent context, setting the application context id, etc
					if (cwac.getParent() == null) {
						// The context instance was injected without an explicit parent -> set
						// the root application context (if any; may be null) as the parent
						cwac.setParent(rootContext);
					}
                      // 重新整理webApplicationContext
					configureAndRefreshWebApplicationContext(cwac);
				}
			}
		}
         // 若不是通過建構函式初始化webApplicationContext,就從
		if (wac == null) {
			// No context instance was injected at construction time -> see if one
			// has been registered in the servlet context. If one exists, it is assumed
			// that the parent context (if any) has already been set and that the
			// user has performed any initialization such as setting the context id
			wac = findWebApplicationContext();
		}
		if (wac == null) {
			// No context instance is defined for this servlet -> create a local one
			wac = createWebApplicationContext(rootContext);
		}

		if (!this.refreshEventReceived) {
			// Either the context is not a ConfigurableApplicationContext with refresh
			// support or the context injected at construction time had already been
			// refreshed -> trigger initial onRefresh manually here.
			onRefresh(wac);
		}

		if (this.publishContext) {
			// Publish the context as a servlet context attribute.
			String attrName = getServletContextAttributeName();
			getServletContext().setAttribute(attrName, wac);
			if (this.logger.isDebugEnabled()) {
				this.logger.debug("Published WebApplicationContext of servlet '" + getServletName() +
						"' as ServletContext attribute with name [" + attrName + "]");
			}
		}

		return wac;
	}

④、接下來分析個人認為比較重要的方法onRefresh(wac);這裡會初始化一系列的資源：

	/**
	 * This implementation calls {@link #initStrategies}.
	 */
	@Override
	protected void onRefresh(ApplicationContext context) {
		initStrategies(context);
	}

	/**
	 * Initialize the strategy objects that this servlet uses.
	 * <p>May be overridden in subclasses in order to initialize further strategy objects.
	 */
	protected void initStrategies(ApplicationContext context) {
         // 初始化MultipartResolver，MultipartResolver主要用來處理檔案上傳
		initMultipartResolver(context);
         // 初始化國際化配置（1.基於URL 2.基於session 3.基於cookie配置）
		initLocaleResolver(context);
         // 初始化頁面主題
		initThemeResolver(context);
         // 初始化處理器對映器
		initHandlerMappings(context);
         // 初始化處理器介面卡
		initHandlerAdapters(context);
         // 初始化HandlerExceptionResolvers,主要用來處理介面異常
		initHandlerExceptionResolvers(context);
         // 初始化RequestToViewNameTranslator，用來處理沒有返回檢視名稱的時候如何確定名稱的類
		initRequestToViewNameTranslator(context);
         // 初始化ViewResolvers，用來根據ModelAndView來選擇具體的View
		initViewResolvers(context);
         // 用來儲存，檢索，管理FlashMap例項
         // FlashMap用來保持flash attributes，flash attributes提供請求儲存屬性
		initFlashMapManager(context);
	}

至此Servlet的init()方法初始化完成~！！！

⑤、接下來就是執行DispatcherServlet的doService()方法：

	/**
	 * Exposes the DispatcherServlet-specific request attributes and delegates to {@link #doDispatch}
	 * for the actual dispatching.
	 */
	@Override
	protected void doService(HttpServletRequest request, HttpServletResponse response) throws Exception {
		if (logger.isDebugEnabled()) {
			String resumed = WebAsyncUtils.getAsyncManager(request).hasConcurrentResult() ? " resumed" : "";
			logger.debug("DispatcherServlet with name '" + getServletName() + "'" + resumed +
					" processing " + request.getMethod() + " request for [" + getRequestUri(request) + "]");
		}

		// Keep a snapshot of the request attributes in case of an include,
		// to be able to restore the original attributes after the include.
		Map<String, Object> attributesSnapshot = null;
		if (WebUtils.isIncludeRequest(request)) {
			attributesSnapshot = new HashMap<String, Object>();
			Enumeration<?> attrNames = request.getAttributeNames();
			while (attrNames.hasMoreElements()) {
				String attrName = (String) attrNames.nextElement();
				if (this.cleanupAfterInclude || attrName.startsWith("org.springframework.web.servlet")) {
					attributesSnapshot.put(attrName, request.getAttribute(attrName));
				}
			}
		}

		// Make framework objects available to handlers and view objects.
         // 給request設定一些屬性引數，後面能用的到
		request.setAttribute(WEB_APPLICATION_CONTEXT_ATTRIBUTE, getWebApplicationContext());
		request.setAttribute(LOCALE_RESOLVER_ATTRIBUTE, this.localeResolver);
		request.setAttribute(THEME_RESOLVER_ATTRIBUTE, this.themeResolver);
		request.setAttribute(THEME_SOURCE_ATTRIBUTE, getThemeSource());

		FlashMap inputFlashMap = this.flashMapManager.retrieveAndUpdate(request, response);
		if (inputFlashMap != null) {
			request.setAttribute(INPUT_FLASH_MAP_ATTRIBUTE, Collections.unmodifiableMap(inputFlashMap));
		}
		request.setAttribute(OUTPUT_FLASH_MAP_ATTRIBUTE, new FlashMap());
		request.setAttribute(FLASH_MAP_MANAGER_ATTRIBUTE, this.flashMapManager);

		try {
              // 核心方法，真正處理請求邏輯的方法
			doDispatch(request, response);
		}
		finally {
			if (!WebAsyncUtils.getAsyncManager(request).isConcurrentHandlingStarted()) {
				// Restore the original attribute snapshot, in case of an include.
				if (attributesSnapshot != null) {
					restoreAttributesAfterInclude(request, attributesSnapshot);
				}
			}
		}
	}

⑥、接下來分析doDispatch()方法，核心的處理邏輯就在該方法中：

protected void doDispatch(HttpServletRequest request, HttpServletResponse response) throws Exception {
		HttpServletRequest processedRequest = request;
		HandlerExecutionChain mappedHandler = null;
		boolean multipartRequestParsed = false;

		WebAsyncManager asyncManager = WebAsyncUtils.getAsyncManager(request);

		try {
			ModelAndView mv = null;
			Exception dispatchException = null;

			try {
                  // spring首先判斷是否是Multipart型別的request
                  // 若是，就轉換request為MultipartHttpServletRequest
				processedRequest = checkMultipart(request);
				multipartRequestParsed = (processedRequest != request);

				// Determine handler for the current request.
                  // 獲取request對應的handler
				mappedHandler = getHandler(processedRequest);
				if (mappedHandler == null || mappedHandler.getHandler() == null) {
                      // 每個請求都對應一個handler，邏輯的實現在handler中
                      // 若沒有找到handler就只能通過response向用戶返回錯誤資訊
					noHandlerFound(processedRequest, response);
					return;
				}

				// Determine handler adapter for the current request.
                  // 獲取request對應的handlerAdapter
				HandlerAdapter ha = getHandlerAdapter(mappedHandler.getHandler());

				// Process last-modified header, if supported by the handler.
                  // last-modified快取機制
				String method = request.getMethod();
				boolean isGet = "GET".equals(method);
				if (isGet || "HEAD".equals(method)) {
					long lastModified = ha.getLastModified(request, mappedHandler.getHandler());
					if (logger.isDebugEnabled()) {
						logger.debug("Last-Modified value for [" + getRequestUri(request) + "] is: " + lastModified);
					}
					if (new ServletWebRequest(request, response).checkNotModified(lastModified) && isGet) {
						return;
					}
				}
				// 方法處理前的攔截器，即前置處理
				if (!mappedHandler.applyPreHandle(processedRequest, response)) {
					return;
				}

				// Actually invoke the handler.
                  // 真正執行handler的方法
				mv = ha.handle(processedRequest, response, mappedHandler.getHandler());

				if (asyncManager.isConcurrentHandlingStarted()) {
					return;
				}
				// 設定預設的檢視
				applyDefaultViewName(processedRequest, mv);
                  // 方法處理後的攔截器，即後置處理
				mappedHandler.applyPostHandle(processedRequest, response, mv);
			}
			catch (Exception ex) {
				dispatchException = ex;
			}
			catch (Throwable err) {
				// As of 4.3, we're processing Errors thrown from handler methods as well,
				// making them available for @ExceptionHandler methods and other scenarios.
				dispatchException = new NestedServletException("Handler dispatch failed", err);
			}
			processDispatchResult(processedRequest, response, mappedHandler, mv, dispatchException);
		}
		catch (Exception ex) {
			triggerAfterCompletion(processedRequest, response, mappedHandler, ex);
		}
		catch (Throwable err) {
			triggerAfterCompletion(processedRequest, response, mappedHandler,
					new NestedServletException("Handler processing failed", err));
		}
		finally {
			if (asyncManager.isConcurrentHandlingStarted()) {
				// Instead of postHandle and afterCompletion
				if (mappedHandler != null) {
					mappedHandler.applyAfterConcurrentHandlingStarted(processedRequest, response);
				}
			}
			else {
				// Clean up any resources used by a multipart request.
				if (multipartRequestParsed) {
					cleanupMultipart(processedRequest);
				}
			}
		}
	}

⑦、先來看看mappedHandler = getHandler(processedRequest);這句程式碼中的getHandler()方法：

protected HandlerExecutionChain getHandler(HttpServletRequest request) throws Exception {
     // spring啟動的時候會把所有的handler都註冊到handlerMappings這個List中
	 // 接下來只要對這個list遍歷
	for (HandlerMapping hm : this.handlerMappings) {
		if (logger.isTraceEnabled()) {
			logger.trace(
					"Testing handler map [" + hm + "] in DispatcherServlet with name '" + getServletName() + "'");
		}
         // 根據request獲取對應的handler
		HandlerExecutionChain handler = hm.getHandler(request);
		if (handler != null) {
			return handler;
		}
	}
	return null;
}

    @Override
	public final HandlerExecutionChain getHandler(HttpServletRequest request) throws Exception {
         // 該方法應該就是獲取我們配置的handlerMapping
         // 若沒有指定具體的handlerMapping就會去取預設的Handler
		Object handler = getHandlerInternal(request);
		if (handler == null) {
			handler = getDefaultHandler();
		}
		if (handler == null) {
			return null;
		}
		// Bean name or resolved handler?
         // 若獲取的handler為String型別，表示則需要根據bean的name去查詢對應的handler
		if (handler instanceof String) {
			String handlerName = (String) handler;
			handler = getApplicationContext().getBean(handlerName);
		}
		// 使用該方法對獲取的handler進行封裝
         // 主要操作就是給handler這條執行鏈上新增攔截器
		HandlerExecutionChain executionChain = getHandlerExecutionChain(handler, request);
		if (CorsUtils.isCorsRequest(request)) {
			CorsConfiguration globalConfig = this.corsConfigSource.getCorsConfiguration(request);
			CorsConfiguration handlerConfig = getCorsConfiguration(handler, request);
			CorsConfiguration config = (globalConfig != null ? globalConfig.combine(handlerConfig) : handlerConfig);
			executionChain = getCorsHandlerExecutionChain(request, executionChain, config);
		}
		return executionChain;
	}

⑧、再來看看HandlerAdapter ha = getHandlerAdapter(mappedHandler.getHandler());中的getHandlerAdapter()方法：
預設是使用SimpleControllerHandlerAdapter。
至於為什麼是SimpleControllerHandlerAdapter，詳情見DispatcherServlet的initHandlerAdapters()方法的註釋

	protected HandlerAdapter getHandlerAdapter(Object handler) throws ServletException {
		for (HandlerAdapter ha : this.handlerAdapters) {
			if (logger.isTraceEnabled()) {
				logger.trace("Testing handler adapter [" + ha + "]");
			}
			if (ha.supports(handler)) {
				return ha;
			}
		}
		throw new ServletException("No adapter for handler [" + handler +
				"]: The DispatcherServlet configuration needs to include a HandlerAdapter that supports this handler");
	}

⑨、接下來在分析mv = ha.handle(processedRequest, response, mappedHandler.getHandler());中handle()方法，真正執行handler的方法：這裡使用預設的SimpleControllerHandlerAdapter進行分析：

	@Override
	public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler)
			throws Exception {

		return ((Controller) handler).handleRequest(request, response);
	}

	@Override
	public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response)
			throws Exception {

		if (HttpMethod.OPTIONS.matches(request.getMethod())) {
			response.setHeader("Allow", getAllowHeader());
			return null;
		}

		// Delegate to WebContentGenerator for checking and preparing.
		checkRequest(request);
		prepareResponse(response);

		// Execute handleRequestInternal in synchronized block if required.
		if (this.synchronizeOnSession) {
			HttpSession session = request.getSession(false);
			if (session != null) {
				Object mutex = WebUtils.getSessionMutex(session);
				synchronized (mutex) {
                      // // 真正執行使用者的controller的方法
					return handleRequestInternal(request, response);
				}
			}
		}
		// 真正執行使用者的controller的方法
		return handleRequestInternal(request, response);
	}

⑩、最後在來看processDispatchResult(processedRequest, response, mappedHandler, mv, dispatchException);方法

前面的設定預設檢視方法applyDefaultViewName(processedRequest, mv);與後置處理方法：mappedHandler.applyPostHandle(processedRequest, response, mv);在這裡就不分析了。

	private void processDispatchResult(HttpServletRequest request, HttpServletResponse response,
			HandlerExecutionChain mappedHandler, ModelAndView mv, Exception exception) throws Exception {

		boolean errorView = false;

		if (exception != null) {
			if (exception instanceof ModelAndViewDefiningException) {
				logger.debug("ModelAndViewDefiningException encountered", exception);
				mv = ((ModelAndViewDefiningException) exception).getModelAndView();
			}
			else {
				Object handler = (mappedHandler != null ? mappedHandler.getHandler() : null);
                  // 異常檢視的處理
				mv = processHandlerException(request, response, handler, exception);
				errorView = (mv != null);
			}
		}

		// Did the handler return a view to render?
		if (mv != null && !mv.wasCleared()) {
              // 根據檢視跳轉頁面
			render(mv, request, response);
			if (errorView) {
				WebUtils.clearErrorRequestAttributes(request);
			}
		}
		else {
			if (logger.isDebugEnabled()) {
				logger.debug("Null ModelAndView returned to DispatcherServlet with name '" + getServletName() +
						"': assuming HandlerAdapter completed request handling");
			}
		}

		if (WebAsyncUtils.getAsyncManager(request).isConcurrentHandlingStarted()) {
			// Concurrent handling started during a forward
			return;
		}

		if (mappedHandler != null) {
			mappedHandler.triggerAfterCompletion(request, response, null);
		}
	}

⑩①、緊接著看檢視跳轉方法render(mv, request, response);

	@Override
	public void render(Map<String, ?> model, HttpServletRequest request, HttpServletResponse response) throws Exception {
		if (logger.isTraceEnabled()) {
			logger.trace("Rendering view with name '" + this.beanName + "' with model " + model +
				" and static attributes " + this.staticAttributes);
		}

		Map<String, Object> mergedModel = createMergedOutputModel(model, request, response);
		prepareResponse(request, response);
         // 處理頁面跳轉，這裡會根據不同的檢視選擇不同的View
		renderMergedOutputModel(mergedModel, getRequestToExpose(request), response);
	}