@SkipValidation 有错误：SkipValidation cannot be resolved to a type，请问怎么解决？
完整项目源代码：github.com/hizhuzhan/StudentManagementSystem
解决了：struts.xml 加 <result name="input">/users/Users_login.jsp</result>
但又出问题了：No result defined for action action.UsersAction and result input
发现了：import org.apache.struts2.interceptor.validation.SkipValidation;