请问不能编译struts程序

我用了这么一句：import org.apache.struts.action.ActionForm;
public class Login extends ActionForm {
它说包org.apache.struts.action不存在，can't resolve ActionForm像javax.servlet.http.HttpServletRequest;
  javax.servlet.http.HttpServletResponse;
  org.apache.struts.action.ActionForm;
  org.apache.struts.action.ActionMapping
这样的不都是struts系统自带的吗？还要我怎么设置???