SmartUpload cannot be resolved to a type这是什么错误

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">



Insert title here


<% SmartUpload smart = new SmartUpload();
smart.initialize(pageContext);
smart.upload();
smart.save("upload");
%>

SmartUpload smart = new SmartUpload();出现这个错误怎么回事
错误提到SmartUpload cannot be resolved to a type

找不到SmartUpload这个类，因为你没有在jsp中添加import，所以jsp中是找不到你的类的。用

<%@page import="java.util.Date" %>

导入以后就可以了