=================The following are some translations of class definitions and class annotations, which still need to be modified. =================
/**
"serial" DispatcherServlet
}
========================The following are some of the more important attributes of this class========== ===============
/** MultipartResolver used by this servlet */private MultipartResolver multipartResolver; /** LocaleResolver used by this servlet */private LocaleResolver localeResolver;/** ThemeResolver used by this servlet */private ThemeResolver themeResolver;/** List of HandlerMappings used by this servlet */private List<HandlerMapping> handlerMappings; //处理器映射列表/** List of HandlerAdapters used by this servlet */private List<HandlerAdapter> handlerAdapters; //处理器适配器列表/** List of HandlerExceptionResolvers used by this servlet */private List<HandlerExceptionResolver> handlerExceptionResolvers; //处理器异常解析器列表/** RequestToViewNameTranslator used by this servlet */private RequestToViewNameTranslator viewNameTranslator;/** FlashMapManager used by this servlet */private FlashMapManager flashMapManager;/** List of ViewResolvers used by this servlet */private List<ViewResolver> viewResolvers; //视图解析器列表
========== ==================The following is the parameterless constructor of the class================== ==========
<span style="color: #008000">/**</span><span style="color: #008000"> * Create a new {</span><span style="color: #808080">@code</span><span style="color: #008000"> DispatcherServlet} that will create its own internal web * application context based on defaults and values provided through servlet * init-params. Typically used in Servlet 2.5 or earlier environments, where the only * option for servlet registration is through {</span><span style="color: #808080">@code</span><span style="color: #008000"> web.xml} which requires the use * of a no-arg constructor. * <p>Calling {</span><span style="color: #808080">@link</span><span style="color: #008000"> #setContextConfigLocation} (init-param 'contextConfigLocation') * will dictate which XML files will be loaded by the * {</span><span style="color: #808080">@linkplain</span><span style="color: #008000"> #DEFAULT_CONTEXT_CLASS default XmlWebApplicationContext} * <p>Calling {</span><span style="color: #808080">@link</span><span style="color: #008000"> #setContextClass} (init-param 'contextClass') overrides the * default {</span><span style="color: #808080">@code</span><span style="color: #008000"> XmlWebApplicationContext} and allows for specifying an alternative class, * such as {</span><span style="color: #808080">@code</span><span style="color: #008000"> AnnotationConfigWebApplicationContext}. * <p>Calling {</span><span style="color: #808080">@link</span><span style="color: #008000"> #setContextInitializerClasses} (init-param 'contextInitializerClasses') * indicates which {</span><span style="color: #808080">@code</span><span style="color: #008000"> ApplicationContextInitializer} classes should be used to * further configure the internal application context prior to refresh(). * </span><span style="color: #808080">@see</span><span style="color: #008000"> #DispatcherServlet(WebApplicationContext)<br> * </span><span style="color: #008000">*/</span><span style="color: #0000ff">public</span><span style="color: #000000"> DispatcherServlet() {</span><span style="color: #0000ff">super</span><span style="color: #000000">(); setDispatchOptionsRequest(</span><span style="color: #0000ff">true</span><span style="color: #000000">); }</span>
================= Below It is the initStrategies(ApplicationContext context) method ==================
which is mainly used to initialize some of the important attributes mentioned above.
//初始化这个DispatcherServlet使用到的策略对象。这个方法有可能会被子类覆盖。protected void initStrategies(ApplicationContext context) { initMultipartResolver(context); initLocaleResolver(context); initThemeResolver(context);
/* * * */ initHandlerMappings(context);
initHandlerExceptionResolvers(context); initRequestToViewNameTranslator(context); initViewResolvers(context); initFlashMapManager(context); }
========================The following is DispatherDoService() method of Servlet==================
doService(HttpServletRequest request, HttpServletResponse response) = WebAsyncUtils.getAsyncManager(request).hasConcurrentResult() ? " resumed" : """DispatcherServlet with name '" + getServletName() + "'" + resumed + " processing " + request.getMethod() + " request for [" + getRequestUri(request) + "]"<String, Object> attributesSnapshot = = HashMap<String, Object><?> attrNames == (.cleanupAfterInclude || attrName.startsWith("org.springframework.web.servlet"= (inputFlashMap != (! (attributesSnapshot !=
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doDispatch(HttpServletRequest request, HttpServletResponse response) == multipartRequestParsed = WebAsyncManager asyncManager == = processedRequest == (processedRequest !=mappedHandler = (mappedHandler == || mappedHandler.getHandler() == HandlerAdapter ha =String method = isGet = "GET" (isGet || "HEAD" lastModified ="Last-Modified value for [" + getRequestUri(request) + "] is: " + ( ServletWebRequest(request, response).checkNotModified(lastModified) && (!mv ==dispatchException = NestedServletException("Handler dispatch failed" NestedServletException("Handler processing failed" (mappedHandler !=
= ================================================== ======================
/** * Return the HandlerExecutionChain for this request. * <p>Tries all handler mappings in order. * @param request current HTTP request * @return the HandlerExecutionChain, or {@code null} if no handler could be found */protected HandlerExecutionChain getHandler(HttpServletRequest request) throws Exception {for (HandlerMapping hm : this.handlerMappings) {if (logger.isTraceEnabled()) { logger.trace("Testing handler map [" + hm + "] in DispatcherServlet with name '" + getServletName() + "'"); } HandlerExecutionChain handler = hm.getHandler(request);if (handler != null) {return handler; } }return null; }
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/** * Render the given ModelAndView. * <p>This is the last stage in handling a request. It may involve resolving the view by name. * @param mv the ModelAndView to render * @param request current HTTP servlet request * @param response current HTTP servlet response * @throws ServletException if view is missing or cannot be resolved * @throws Exception if there's a problem rendering the view */protected void render(ModelAndView mv, HttpServletRequest request, HttpServletResponse response) throws Exception {// Determine locale for request and apply it to the response.Locale locale = this.localeResolver.resolveLocale(request); response.setLocale(locale); View view;if (mv.isReference()) {// We need to resolve the view name.view = resolveViewName(mv.getViewName(), mv.getModelInternal(), locale, request);if (view == null) {throw new ServletException("Could not resolve view with name '" + mv.getViewName() + "' in servlet with name '" + getServletName() + "'"); } }else {// No need to lookup: the ModelAndView object contains the actual View object.view = mv.getView();if (view == null) {throw new ServletException("ModelAndView [" + mv + "] neither contains a view name nor a " + "View object in servlet with name '" + getServletName() + "'"); } }// Delegate to the View object for rendering.if (logger.isDebugEnabled()) { logger.debug("Rendering view [" + view + "] in DispatcherServlet with name '" + getServletName() + "'"); }try {if (mv.getStatus() != null) { response.setStatus(mv.getStatus().value()); } view.render(mv.getModelInternal(), request, response); }catch (Exception ex) {if (logger.isDebugEnabled()) { logger.debug("Error rendering view [" + view + "] in DispatcherServlet with name '" +getServletName() + "'", ex); }throw ex; } }
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/** * Resolve the given view name into a View object (to be rendered). * <p>The default implementations asks all ViewResolvers of this dispatcher. * Can be overridden for custom resolution strategies, potentially based on * specific model attributes or request parameters. * @param viewName the name of the view to resolve * @param model the model to be passed to the view * @param locale the current locale * @param request current HTTP servlet request * @return the View object, or {@code null} if none found * @throws Exception if the view cannot be resolved * (typically in case of problems creating an actual View object) * @see ViewResolver#resolveViewName */protected View resolveViewName(String viewName, Map<String, Object> model, Locale locale, HttpServletRequest request) throws Exception {for (ViewResolver viewResolver : this.viewResolvers) { View view = viewResolver.resolveViewName(viewName, locale);if (view != null) {return view; } }return null; }
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