欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页

诡异的InternalResourceViewResolver

程序员文章站 2022-06-07 13:06:24
...
现象:
<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <beans:property name="prefix" value="/WEB-INF/views/" />
    <beans:property name="suffix" value=".jsp" />
</beans:bean> 
 
<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <beans:property name="prefix" value="/WEB-INF/views/" />
    <beans:property name="suffix" value=".html" />
</beans:bean>
   第一种可以正常工作,第二种不行,当然了/WEB-INF/views里面 jsp和html结尾的都可以。
  
WARN : org.springframework.web.servlet.PageNotFound - No mapping found for HTTP request with URI [/myapp/WEB-INF/views/home.html] in DispatcherServlet with name 'appServlet'
    
   错误的原因就是html页面被加上了/myapp前缀,myapp为我的工程名称。
   分析,从spring的InternalResourceViewResolver入手:
   
@Override
    protected AbstractUrlBasedView buildView(String viewName) throws Exception {
         InternalResourceView view = (InternalResourceView) super .buildView(viewName);
          if (this .alwaysInclude != null) {
             view.setAlwaysInclude( this.alwaysInclude );
         }
          if (this .exposeContextBeansAsAttributes != null) {
             view.setExposeContextBeansAsAttributes( this.exposeContextBeansAsAttributes );
         }
          if (this .exposedContextBeanNames != null) {
             view.setExposedContextBeanNames( this.exposedContextBeanNames );
         }
         view.setPreventDispatchLoop( true);
          return view;
    }
    
      从代码来看这个地方只是构建了一个view,应该是没有问题的,最终我跟踪代码到InternalResourceViewrenderMergedOutputModel函数。
    
// Determine the path for the request dispatcher.
         String dispatcherPath = prepareForRendering(requestToExpose, response);

          // Obtain a RequestDispatcher for the target resource (typically a JSP).
         RequestDispatcher rd = getRequestDispatcher(requestToExpose, dispatcherPath);
          if (rd == null) {
              throw new ServletException("Could not get RequestDispatcher for [" + getUrl() +
                       "]: Check that the corresponding file exists within your web application archive!");
         }

          // If already included or response already committed, perform include, else forward.
          if (useInclude(requestToExpose, response)) {
             response.setContentType(getContentType());
              if (logger .isDebugEnabled()) {
                  logger.debug("Including resource [" + getUrl() + "] in InternalResourceView '" + getBeanName() + "'" );
             }
             rd.include(requestToExpose, response);
         }

          else {
              // Note: The forwarded resource is supposed to determine the content type itself.
             exposeForwardRequestAttributes(requestToExpose);
              if (logger .isDebugEnabled()) {
                  logger.debug("Forwarding to resource [" + getUrl() + "] in InternalResourceView '" + getBeanName() + "'");
             }
             rd.forward(requestToExpose, response);
         }
     从这段代码来看,prepareForRendering这个函数是来准备url的,也就是刚才的InternalResourceViewRoslver的解析的结果,从调试来看,这两个的配置的返回的路径一致。那问题应该出在RequestDispatcher的fowward函数了,从这个地方来看,又回到了servlet里面,然后我写了个小例子。
     
    从小例子来看是完全一样的。
    
 10:55:58.283 [http-bio-8080-exec-4] DEBUG o.s.web.servlet.view.JstlView - Added model object 'org.springframework.validation.BindingResult.user' of type [org.springframework.validation.BeanPropertyBindingResult] to request in view with name 'index'
10:55:58.283 [http-bio-8080-exec-4] DEBUG o.s.web.servlet.view.JstlView - Added model object 'user' of type [microshield.com.cn.radius.admin.model.User] to request in view with name 'index'
10:55:58.284 [http-bio-8080-exec-4] DEBUG o.s.web.servlet.view.JstlView - Forwarding to resource [/WEB-INF/pages/index.jsp] in InternalResourceView 'index'
10:56:11.719 [http-bio-8080-exec-4] DEBUG o.s.web.servlet.DispatcherServlet - Successfully completed request

10:48:22.161 [http-bio-8080-exec-10] DEBUG o.s.web.servlet.view.JstlView - Forwarding to resource [/WEB-INF/pages/index.html] in InternalResourceView 'index'
10:48:22.178 [http-bio-8080-exec-10] DEBUG o.s.web.servlet.DispatcherServlet - DispatcherServlet with name 'Spring MVC Dispatcher Servlet' processing GET request for [/microshield-radius/WEB-INF/pages/index.html]
10:48:22.180 [http-bio-8080-exec-10] DEBUG o.s.w.s.m.a.DefaultAnnotationHandlerMapping - Looking for URL mappings in application context: WebApplicationContext for namespace 'Spring MVC Dispatcher Servlet-servlet': startup date [Mon Sep 15 10:47:54 CST 2014]; parent: Root WebApplicationContext
10:48:22.182 [http-bio-8080-exec-10] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'userAction'
   
诡异的InternalResourceViewResolver
            
    
    博客分类: spring spring mvc 
 
诡异的InternalResourceViewResolver
            
    
    博客分类: spring spring mvc 
 
      从调用的轨迹来看,jsp file直接在response流里面进行了处理,但是html file又发起了一次请求。
     但是我在普通的servlet里面运行工程是可以的,由于没有时间下载tomcat的源码进行调试,没有看到具体的代码走的分支,有熟悉的给帮我解答下。
  • 诡异的InternalResourceViewResolver
            
    
    博客分类: spring spring mvc 
  • 大小: 61.5 KB
  • 诡异的InternalResourceViewResolver
            
    
    博客分类: spring spring mvc 
  • 大小: 102.4 KB
相关标签: spring mvc