工程的目录结构以及所需的jar文件如下：
其中tanchu.jpg图片如下：
1.新建一个jsp文件UpTest.jsp
<%@ 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">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<style type="text/css">
#download{
border: 1px solid red;
height:150px;
width:300px;
position:absolute;
}
</style>
<script type="text/javascript">
//隐藏图片
function CloseCodeWindow()
{
var download = document.getElementById( "download");
download.style.display = "none";
}
</script>
</head>
<body>
<div id="download">
<img src="images/tanchu.jpg" width="300" height="124" border="0" usemap="#Map" /><!--通过usemap与下面的map元素关联-->
</div>
<!--map元素指定图片可点击区域-->
<map name="Map" id="Map">
<area shape="rect" coords="73,52,225,98 " href="<%=request.getContextPath() %>/downloadpdfdata.jsp" /><!-- 这个坐标对应文字区域"点击下载该凭证" -->
<area shape="rect" coords="263,5,293,33" href="javascript:CloseCodeWindow();"><!-- 这个坐标对应图片的关闭区域 -->
</map>
</body>
</html>2.新建downloadpdfdata.jsp
<%
try{
pageContext.setAttribute("fileName", "D://HelloWorld.java"); //在D盘中存放HelloWorld.java文件，当然这个值可以通过session获取
String strFileName = (String)pageContext.getAttribute("fileName");
if(strFileName != null){
com.jspsmart.upload.SmartUpload su = new com.jspsmart.upload.SmartUpload();
su.initialize(pageContext); //使用jsp内置对象pageContext初始化
su.setContentDisposition(null);
su.downloadFile(strFileName);//下载D盘下的HelloWorld.java文件
}
}catch (Exception e){
out.write("<a>" + e.getMessage() + "</a>");
}
%>
