簡單介紹了一個請求的處理過程， 簡略描述了調用過程，并沒有涉及過多細節，如url匹配,報文解析轉換等。

<SpringMVC源碼分析（2）DispatcherServlet的初始化>:介紹了servlet的初始化過程，尤其initStrategies方法。

本文主要總結DispatcherServlet幾個重要組件的關系。

1.類圖

該類圖并沒有全面的描述SpringMVC相關類，重點說明組件的關系。

該類圖基于springmvc3.0.5版本。

很多類屬性并沒有完全羅列，進行了取舍。

基于DispatcherServlet,而且深度盡量適可而止，否則造成圖復雜混亂。

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2.HanlerMapping組件介紹

2.1?HanlerMapping類圖

HanlerMapping是springmvc中完成url到controller映射的組件。

2.2?HanlerMappingAPI

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public?interface?HandlerMapping?{ ????//根據選擇策略，返回Handler ????HandlerExecutionChain?getHandler(HttpServletRequest?request)?throws?Exception; }

3.HandlerAdapter

3.1類圖

是MVC framework SPI ；負責具體干活。如調用方法，參數解析等。

3.2 API

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public?interface?HandlerAdapter?{ ???? ???/** ????????????判斷是否可以處理handler ????*/ ???boolean?supports(Object?handler);? ???? ???/** ????*?處理請求 ????*/ ???ModelAndView?handle(HttpServletRequest?request,?HttpServletResponse?response,?Object?handler)?throws?Exception; ???/** ????*?getLastModified ????*/ ???long?getLastModified(HttpServletRequest?request,?Object?handler); }

4.HandlerExceptionResolver

4.1 HandlerExceptionResolver類圖

專門處理異常情況，根據異常情況，構造ModelAndView

4.2 HandlerExceptionResolver API

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public?interface?HandlerExceptionResolver?{ ???/** ????*?處理異常 ????*/ ???ModelAndView?resolveException( ?????????HttpServletRequest?request,?HttpServletResponse?response,?Object?handler,?Exception?ex); }

5.? ViewResolver

5.1 ViewResolver類圖

作用：將string的視圖名稱解析為View類型的視圖

5.2 ViewResolver API

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public?interface?ViewResolver?{ ???/**? ????*?Resolve?the?given?view?by?name. ???????解析視圖 ????*/ ???View?resolveViewName(String?viewName,?Locale?locale)?throws?Exception; }

6.RequestToViewNameTranslator

默認實現是DefaultRequestToViewNameTranslator.主要作用是根據請求信息獲取視圖名稱。

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public?interface?RequestToViewNameTranslator?{ ???String?getViewName(HttpServletRequest?request)?throws?Exception; }

7.LocaleResolver

7.1 LocaleResolver類圖

從request解析Locale,實現本地化;一般使用在解析視圖時使用；和使用國際化資源和主題時使用

7.2 LocaleResolver API

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public?interface?LocaleResolver?{ ??/** ???*?Resolve?the?current?locale?via?the?given?request. ???*?Should?return?a?default?locale?as?fallback?in?any?case. ???*?@param?request?the?request?to?resolve?the?locale?for ???*?@return?the?current?locale?(never?<code>null</code>) ???*/ ???Locale?resolveLocale(HttpServletRequest?request); ??/** ???*?Set?the?current?locale?to?the?given?one. ???*?@param?request?the?request?to?be?used?for?locale?modification ???*?@param?response?the?response?to?be?used?for?locale?modification ???*?@param?locale?the?new?locale,?or?<code>null</code>?to?clear?the?locale ????*?@throws?UnsupportedOperationException?if?the?LocaleResolver?implementation ????*?does?not?support?dynamic?changing?of?the?theme ???*/ ???void?setLocale(HttpServletRequest?request,?HttpServletResponse?response,?Locale?locale); }

8.ThemeResolver

8.1 ThemeResolver類圖

主要用來設置主題。

8.2 API

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public?interface?ThemeResolver?{ ??/** ???*?Resolve?the?current?theme?name?via?the?given?request. ???*?Should?return?a?default?theme?as?fallback?in?any?case. ???*?@param?request?request?to?be?used?for?resolution ???*?@return?the?current?theme?name ???*/ ???String?resolveThemeName(HttpServletRequest?request); ??/** ???*?Set?the?current?theme?name?to?the?given?one. ???*?@param?request?request?to?be?used?for?theme?name?modification ???*?@param?response?response?to?be?used?for?theme?name?modification ???*?@param?themeName?the?new?theme?name ????*?@throws?UnsupportedOperationException?if?the?ThemeResolver?implementation ????*?does?not?support?dynamic?changing?of?the?theme ???*/ ???void?setThemeName(HttpServletRequest?request,?HttpServletResponse?response,?String?themeName); }

9.MultipartResolver?

默認實現為CommonsMultipartResolver，處理文件上傳請求。

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public?interface?MultipartResolver?{ ???/** ????*?Determine?if?the?given?request?contains?multipart?content. ????*/ ???boolean?isMultipart(HttpServletRequest?request); ???/** ????*?Parse?the?given?HTTP?request?into?multipart?files?and?parameters, ????*?and?wrap?the?request?inside?a ????*/ ???MultipartHttpServletRequest?resolveMultipart(HttpServletRequest?request)?throws?MultipartException; ???/** ????*?Cleanup?any?resources?used?for?the?multipart?handling, ????*/ ???void?cleanupMultipart(MultipartHttpServletRequest?request); }

10 總結。

簡單介紹了下各個組件，每個組件都各司其職，互相配合。才有了強大的SpringMVC功能。在以后的文章里，針對每個組件，會結合具體例子，由淺入深式的進行剖析。

另外一個重要的核心部分是HandlerMethodInvoker，涉及的東西比較多，非常有看頭。

本文轉自 randy_shandong 51CTO博客，原文鏈接：http://blog.51cto.com/dba10g/1878735，如需轉載請自行聯系原作者

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