【JSP上传图片并自动生成缩略图】

JSP上传图片并自动生成缩略图

  1、uploadimage.jsp

  <%@ page contentType="text/html;charset=gb2312" language="java" import="java.io.*,java.awt.Image,java.awt.image.*,com.sun.image.codec.jpeg.*,java.sql.*,com.jspsmart.upload.*,java.util.*,cn.oof.database.*,cn.oof.house.*"%>

  <%

  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");

  //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='upfile.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='upfile.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);

  //out.print(filename);

  //-----------------------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=200;

  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;

  }

posted on 2013-09-23 15:31  挖掘者者者  阅读(513)  评论(0编辑  收藏  举报