web.xml初始化过程

大学学servlet这部分的老师讲了web.xml的加载过程，当时不懂也不理解，配置过程也是随意配置，后来在公司实际项目搭建项目过程，开始认识到这些问题，web.xml加载过程

context-param >> listener >> filter >> servlet

<!-- Spring和mybatis的配置文件 -->
<context-param>
  <param-name>contextConfigLocation</param-name>
  <param-value>classpath:spring-mybatis.xml</param-value>
</context-param>

<!-- Spring监听器 -->
<listener>
  <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

<!-- 防止Spring内存溢出监听器 -->
<listener>
  <listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class>
</listener>

<!--中文处理过滤，如果不设计中文的处理下面这部分可以移除-->
<filter>
  <filter-name>encodingFilter</filter-name>
  <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
  <init-param>
    <param-name>encoding</param-name>
    <param-value>UTF-8</param-value>
  </init-param>
  <init-param>
    <param-name>forceEncoding</param-name>
    <param-value>true</param-value>
  </init-param>
</filter>
<filter-mapping>
  <filter-name>encodingFilter</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>

<!-- Spring MVC servlet -->
<servlet>
  <servlet-name>springmvc</servlet-name>
  <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
  <init-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:spring-mvc.xml</param-value>
  </init-param>
  <load-on-startup>1</load-on-startup>
  <async-supported>true</async-supported>
</servlet>
<servlet-mapping>
  <servlet-name>springmvc</servlet-name>
  <!-- 此处可以可以配置成*.do，对应struts的后缀习惯 /表示拦截所有请求 -->
  <url-pattern>/</url-pattern>
</servlet-mapping>