ubuntu上假设openvpn

当我把filter中的init-param删除时，这个bug：java.lang.IllegalStateException: No WebApplicationContext found: no ContextLoaderListener or DispatcherServlet registered解决

<filter>
    <filter-name>springSecurityFilterChain</filter-name>
    <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
    <init-param>
        <param-name>contextAttribute</param-name>
        <param-value>org.springframework.web.servlet.FrameworkServlet.CONTEXT.spring</param-value>
    </init-param>
</filter>