java - struts运行一直报错，不知什么问题

Answer 1

Your filter in the Web.xml file is not checked. The class in Filter does not only map other struts2 core filters. How can struts handle it for you? ?
Code example is as follows:

<filter>
      <filter-name>strust2</filter-name>
      <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</fitler-class>
  </filter>
  <filter-mapping>
      <filter-name>strust2</filter-name>
      <url-pattern>/*</url-pattern>
  </filter-mapping>