jsp上传头像以及生成缩略图

<%@ page autoFlush="false" contentType="text/html;charset=utf-8" language="java" import="java.io.*,java.awt.Image,java.awt.image.*,com.sun.image.codec.jpeg.*,java.sql.*,com.jspsmart.upload.*,java.util.*,java.io.FileInputStream,java.io.FileOutputStream,java.awt.*"%>
<%@ page import="com.blog.vo.*" %>
<%
SmartUpload mySmartUpload =new SmartUpload();
long file_size_max=4000000;
String fileName2="",ext="",testvar="";
String url="uploadfile/images/"; //应保证在根目录中有此目录的存在
//初始化
mySmartUpload.initialize(pageContext);
//只允许上载此类文件
try {
mySmartUpload.setAllowedFilesList("jpg,gif,JPG,GIF");
//上载文件 
mySmartUpload.upload();
} catch (Exception e){
%>
<SCRIPT language=javascript>
alert("只允许上传.jpg和.gif类型图片文件");
window.location='face.jsp';
</script>
<%
}
try{ 
com.jspsmart.upload.File myFile = mySmartUpload.getFiles().getFile(0);
if (myFile.isMissing()){%>
<SCRIPT language=javascript>
alert("请先选择要上传的文件");
window.location='face.jsp';
</script>
<%}
else{
//String myFileName=myFile.getFileName(); //取得上载的文件的文件名
ext= myFile.getFileExt(); //取得后缀名
int file_size=myFile.getSize(); //取得文件的大小 
String saveurl="";
if(file_size<file_size_max){
//更改文件名，取得当前上传时间的毫秒数值
Calendar calendar = Calendar.getInstance();
String filename = String.valueOf(calendar.getTimeInMillis()); 
saveurl=request.getRealPath("/")+url;
saveurl+=filename+"."+ext; //保存路径
myFile.saveAs(saveurl,mySmartUpload.SAVE_PHYSICAL);
//-----------------------上传完成，开始生成缩略图------------------------- 
java.io.File file = new java.io.File(saveurl); //读入刚才上传的文件
String newurl=request.getRealPath("/")+url+filename+"_min."+ext; //新的缩略图保存地址
Image src = javax.imageio.ImageIO.read(file); //构造Image对象
float tagsize=110;
int old_w=src.getWidth(null); //得到源图宽
int old_h=src.getHeight(null); 
int new_w=0;
int new_h=0; //得到源图长
int tempsize;
float tempdouble; 
if(old_w>old_h){
tempdouble=old_w/tagsize;
}else{
tempdouble=old_h/tagsize;
}
new_w=Math.round(old_w/tempdouble);
new_h=Math.round(old_h/tempdouble);//计算新图长宽
BufferedImage image = new BufferedImage(new_w,new_h,BufferedImage.TYPE_INT_RGB);//创建一个BufferedImage来作为图像*作容器 
Graphics g = image.getGraphics(); //创建一个绘图环境来进行绘制图象 
g.drawImage(src,0,0,new_w,new_h,null); //将原图像数据流载入这个BufferedImage 
g.setFont(new Font("Times New Roman",Font.PLAIN,24)); //设定文本字体 
String rand = ""; 
g.setColor(Color.red); //设定文本颜色 
g.drawString(rand,new_w-200,new_h-10); //向BufferedImage写入文本字符 
g.dispose(); //使更改生效

FileOutputStream newimage=new FileOutputStream(newurl); //输出到文件流
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(newimage); 
encoder.encode(image); //近JPEG编码
newimage.close(); 
UserInfo ui = (UserInfo)request.getSession().getAttribute("userinfo");
ui.setFace(url+filename+"_min."+ext);
session.setAttribute("userinfo",ui);
String turl="face.jsp?src="+url+filename+"_min."+ext;
out.print("<SCRIPT language='javascript'>");
out.print("window.location='"+turl+"'");
out.print("</SCRIPT>");
}
else{
out.print("<SCRIPT language='javascript'>");
out.print("alert('上传文件大小不能超过"+(file_size_max/1000)+"K');");
out.print("window.location='face.jsp;'");
out.print("</SCRIPT>");
}
}
}catch (Exception e){

e.toString();

}

%>