How does the STRUTS2 syntax--error page capture?

If the address bar is entered without a suffix or the action is a suffix, the nonexistent page jumps to error.jsp:

Struts.xml Configuration "

<package name= "Default" namespace= "/" extends= "Struts-default" ><default-action-ref name= "error" ></ default-action-ref>        <action name= "error" >         <result>/error.jsp</result>         </ Action></package>        

If JSP capture requires the configuration of Web. XML:

<error-page>error.jsp</error-page>

　　

The second way, with wildcard characters:

<!--the second method of the default action, must be placed on top of all child packages--    <package name= "error" namespace= "" extends= "Default" >    <action name= "* *" >    <result>/error.jsp</result>        </action>           </package >

　　

Tomcat hyperlinks are garbled in Chinese, and can be followed by a statement in Server.xml Riga:

<connector port= "8080"----------uriencoding= "UTF-8"/>

　　

　

How does the STRUTS2 syntax--error page capture?