由于SpringBoot默認是以jar包的方式啟動嵌入式的Servlet容器來啟動SpringBoot的web應用，沒有web.xml文件。 注冊三大組件用以下方式 ServletRegistrationBean ```java //注冊三大組件 @Bean public ServletRegistrationBean myServlet(){ ServletRegistrationBean registrationBean = new ServletRegistrationBean(new MyServlet(),"/myServlet"); return registrationBean; } ``` FilterRegistrationBean ```java @Bean public FilterRegistrationBean myFilter(){ FilterRegistrationBean registrationBean = new FilterRegistrationBean(); registrationBean.setFilter(new MyFilter()); registrationBean.setUrlPatterns(Arrays.asList("/hello","/myServlet")); return registrationBean; } ``` ServletListenerRegistrationBean ```java @Bean public ServletListenerRegistrationBean myListener(){ ServletListenerRegistrationBean<MyListener> registrationBean = new ServletListenerRegistrationBean<>(new MyListener()); return registrationBean; } ``` SpringBoot幫我們自動SpringMVC的時候，自動的注冊SpringMVC的前端控制器；DIspatcherServlet； DispatcherServletAutoConfiguration中： ```java @Bean(name = DEFAULT_DISPATCHER_SERVLET_REGISTRATION_BEAN_NAME) @ConditionalOnBean(value = DispatcherServlet.class, name = DEFAULT_DISPATCHER_SERVLET_BEAN_NAME) public ServletRegistrationBean dispatcherServletRegistration( DispatcherServlet dispatcherServlet) { ServletRegistrationBean registration = new ServletRegistrationBean( dispatcherServlet, this.serverProperties.getServletMapping()); //默認攔截： / 所有請求；包靜態資源，但是不攔截jsp請求； /*會攔截jsp //可以通過server.servletPath來修改SpringMVC前端控制器默認攔截的請求路徑 registration.setName(DEFAULT_DISPATCHER_SERVLET_BEAN_NAME); registration.setLoadOnStartup( this.webMvcProperties.getServlet().getLoadOnStartup()); if (this.multipartConfig != null) { registration.setMultipartConfig(this.multipartConfig); } return registration; } ``` 2）、SpringBoot能不能支持其他的Servlet容器；