本文实例为大家分享了javaweb多文件上传及zip打包下载的具体代码,供大家参考,具体内容如下
项目中经常会使用到文件上传及下载的功能。本篇文章总结场景在javaweb环境下,多文件上传及批量打包下载功能,包括前台及后台部分。
首先明确一点:
无法通过页面的无刷新ajax请求,直接发下载、上传请求。上传和下载,均需要在整页请求的基础上实现。项目中一般通过构建form表单形式实现这一功能。
一、多文件上传
项目需求为实现多图片上传功能。参考测试了网上找到的众多插件方法后,决定选用jquery原始上传方案。以下按步骤贴出具体代码。
1、html部分(可省略使用js构建)
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<form id= "uploadform" method= "post" enctype= "multipart/form-data" > <input type= "file" hidden name= "fileimage" multiple/> <a href= "javascript:void(0);" rel= "external nofollow" rel= "external nofollow" id= "filesubmit" onclick= "uploadfilemulti()" >上传资料</a> </form> |
有几点说明:
1. form中 enctype=”multipart/form-data”
2. 例中使用标签,构建submit
2、js部分
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var formdata = new formdata($( "#uploadform" )[ 0 ]); formdata.append( "foldname" , "datumlist" ); //设置父级文件夹名称 formdata.append( "odercode" , selfordercode); formdata.append( "datumtype" , datumtype); $.ajax({ type: "post" , data: formdata, url: "order/datumlist/batchinsertdatumlists" , contenttype: false , processdata: false , success: function (result) { if (result.success) { //清空框文件内容 $( "#fileimage" ).val( "" ); var obj = document.getelementbyid( 'fileimage' ); obj.outerhtml = obj.outerhtml; refreshdatumlist(); showsuccesstoast(result.message); } else { showwarningtoast(result.message); } }, error: function () { showerrortoast( '请求失败!' ) } }); |
以上有几点说明:
1. var formdata = new formdata($(“#uploadform”)[0]);
2. 使用 formdata.append(“odercode”, selfordercode); 添加其他参数
java后台
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multiparthttpservletrequest mrequest = (multiparthttpservletrequest) request; list<multipartfile> files = mrequest.getfiles( "fileimage" ); |
以上有几点说明:
1. 获取multiparthttpservletrequest,对应file标签的name
二、文件批量下载
本项目中,需求为批量下载某一批次文件。使用zip在服务器压缩文件,之后将文件下载到客户机。
网上查询,使用java自带的文件输出类不能解决压缩文件中文件名乱码的问题。解决方法:使用ant.jar包,创建压缩文件时,可以设置文件的编码格式,文件名乱码的问题就解决了。
html部分(可省略使用js构建)
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<form id= "uploadform" method= "post" enctype= "multipart/form-data" > <div class = "product-dl" > <input type= "hidden" name= "ordercode" /> <input type= "hidden" name= "datumtype" /> <a href= "javascript:void(0);" rel= "external nofollow" rel= "external nofollow" class = "btn" onclick= "batchdatumlistdownload()" >批量下载</a> </div> </form> |
js部分
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//批量下载 function batchdatumlistdownload() { var param = {}; param.datumtype = $( "#datumtypeq" ).val(); if (param.datumtype == - 1 ) { param.datumtype = null ; //查询所有 } param.ordercode = selfordercode; $( "#uploadform input[name=ordercode]" ).val(param.ordercode); $( "#uploadform input[name=datumtype]" ).val(param.datumtype); var form = $( "#uploadform" )[ 0 ]; form.action = "order/datumlist/batchdownloaddatumlist" ; form.method = "post" ; form.submit(); //表单提交 } |
后台部分
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public void batchdownloaddatumlist(datumlistvo datumlistvo, httpservletresponse response) { try { //查询文件列表 list<datumlistvo> volist = datumlistservice.querydatumlists(datumlistvo); //压缩文件 list<file> files = new arraylist<>(); for (datumlistvo vo : volist) { file file = new file(vo.getdatumurl()); files.add(file); } string filename = datumlistvo.getordercode() + "_" + datumlistvo.getdatumtype() + ".zip" ; //在服务器端创建打包下载的临时文件 string globaluploadpath = "" ; string osname = system.getproperty( "os.name" ); if (osname.tolowercase().indexof( "windows" ) >= 0 ) { globaluploadpath = globalkeys.getstring(globalkeys.windows_upload_path); } else if (osname.tolowercase().indexof( "linux" ) >= 0 || osname.tolowercase().indexof( "mac" ) >= 0 ) { globaluploadpath = globalkeys.getstring(globalkeys.linux_upload_path); } string outfilepath = globaluploadpath + file.separator + filename; file file = new file(outfilepath); //文件输出流 fileoutputstream outstream = new fileoutputstream(file); //压缩流 zipoutputstream toclient = new zipoutputstream(outstream); //设置压缩文件内的字符编码,不然会变成乱码 toclient.setencoding( "gbk" ); ziputil.zipfile(files, toclient); toclient.close(); outstream.close(); ziputil.downloadzip(file, response); } catch (exception e) { e.printstacktrace(); } } |
其中ziputil.java
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/** * 压缩文件列表中的文件 * * @param files * @param outputstream * @throws ioexception */ public static void zipfile(list files, zipoutputstream outputstream) throws ioexception, servletexception { try { int size = files.size(); //压缩列表中的文件 for ( int i = 0 ; i < size; i++) { file file = (file) files.get(i); try { zipfile(file, outputstream); } catch (exception e) { continue ; } } } catch (exception e) { throw e; } } /** * 将文件写入到zip文件中 * * @param inputfile * @param outputstream * @throws exception */ public static void zipfile(file inputfile, zipoutputstream outputstream) throws ioexception, servletexception { try { if (inputfile.exists()) { if (inputfile.isfile()) { fileinputstream instream = new fileinputstream(inputfile); bufferedinputstream binstream = new bufferedinputstream(instream); zipentry entry = new zipentry(inputfile.getname()); outputstream.putnextentry(entry); final int max_byte = 10 * 1024 * 1024 ; //最大的流为10m long streamtotal = 0 ; //接受流的容量 int streamnum = 0 ; //流需要分开的数量 int leavebyte = 0 ; //文件剩下的字符数 byte [] inoutbyte; //byte数组接受文件的数据 streamtotal = binstream.available(); //通过available方法取得流的最大字符数 streamnum = ( int ) math.floor(streamtotal / max_byte); //取得流文件需要分开的数量 leavebyte = ( int ) streamtotal % max_byte; //分开文件之后,剩余的数量 if (streamnum > 0 ) { for ( int j = 0 ; j < streamnum; ++j) { inoutbyte = new byte [max_byte]; //读入流,保存在byte数组 binstream.read(inoutbyte, 0 , max_byte); outputstream.write(inoutbyte, 0 , max_byte); //写出流 } } //写出剩下的流数据 inoutbyte = new byte [leavebyte]; binstream.read(inoutbyte, 0 , leavebyte); outputstream.write(inoutbyte); outputstream.closeentry(); //closes the current zip entry and positions the stream for writing the next entry binstream.close(); //关闭 instream.close(); } } else { throw new servletexception( "文件不存在!" ); } } catch (ioexception e) { throw e; } } /** * 下载打包的文件 * * @param file * @param response */ public static void downloadzip(file file, httpservletresponse response) { try { // 以流的形式下载文件。 bufferedinputstream fis = new bufferedinputstream( new fileinputstream(file.getpath())); byte [] buffer = new byte [fis.available()]; fis.read(buffer); fis.close(); // 清空response response.reset(); outputstream toclient = new bufferedoutputstream(response.getoutputstream()); response.setcontenttype( "application/octet-stream" ); response.setheader( "content-disposition" , "attachment;filename=" + file.getname()); toclient.write(buffer); toclient.flush(); toclient.close(); file.delete(); //将生成的服务器端文件删除 } catch (ioexception ex) { ex.printstacktrace(); } } |
以上基本满足文件上传下载所需。
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持服务器之家。
原文链接:https://blog.csdn.net/qq_37878879/article/details/77197448