HTTP Status 404 - No result defined for action com.csdhsm.struts.action.LoginAction and result error

智商拙计的问题，没有找到为类LoginAction和error找到定义，然后重新去struts.xml去看，我类个去，我居然把result写成了ERROR

<result name="ERROR">/WEB-INF/content/error.jsp</result>

再看看Action类的源代码

    /**
     * The action execution was a failure.
     * Show an error view, possibly asking the
     * user to retry entering data.
     */
    public static final String ERROR = "error";

把ERROR改回成error，OK，问题解决。