java 批量下载附件

批量下载附件"/>

java 批量下载附件

上传附件代码：借助commons-fileupload-1.2.jar

package com.str;

import java.io.BufferedInputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.util.Iterator;

import java.util.List;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apachemons.fileupload.FileItem;

import org.apachemons.fileupload.FileUploadException;

import org.apachemons.fileupload.disk.DiskFileItemFactory;

import org.apachemons.fileupload.servlet.ServletFileUpload;

public class UploadServlet extends HttpServlet {

@Override

protected void doPost(HttpServletRequest req, HttpServletResponse resp)

throws ServletException, IOException {

doGet(req, resp);

}

@Override

protected void doGet(HttpServletRequest req, HttpServletResponse resp)

throws ServletException, IOException {

HttpServletRequest request = (HttpServletRequest)req;

HttpServletResponse response = (HttpServletResponse)resp;

/* response.setContentType("text/html;charset=gb2312");

response.setCharacterEncoding("utf-8");*/

OutputStream outputStream = null;

InputStream inputStream = null;

DiskFileItemFactory factory = new DiskFileItemFactory();

ServletFileUpload fileUpload = new ServletFileUpload(factory);

try {

List items = fileUpload.parseRequest(request);

for (Iterator iterator = items.iterator(); iterator.hasNext();) {

FileItem name = (FileItem) iterator.next();

if(!name.isFormField()){

String fieldName  = name.getFieldName();  //这个是name值

String fileName = name.getName();     //这个是全路径

String lastFileName ="";

//这句话获取的是源文件的原名称，不做任何修改

String oldNamePath = fileName.substring(fileName.lastIndexOf("\\")+1);

if(fileName.endsWith(".docx")|| fileName.endsWith(".xls")){

lastFileName = request.getRealPath("/")+"\\upload\\"+ oldNamePath;

outputStream = new FileOutputStream(new File(lastFileName ));

inputStream = name.getInputStream();

byte[] bs = new byte[1024];

int length = 0;

while(null != inputStream && (length = inputStream.read(bs))!=-1){

outputStream.write(bs);

}

}

outputStream.flush();

}

//把lastFileName存到数据库(这里就不写了不只lz用的什么方式)}

}

} catch (Exception e) {

e.printStackTrace();

}

}

}

单个下载文件，批量下载文件代码：借助于ant.jar包的ZipOutputStream、ZipEntry

package com.str;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apache.tools.zip.ZipEntry;

import org.apache.tools.zip.ZipOutputStream;

public class LoadServlet  extends HttpServlet {

@Override

/*protected void doGet(HttpServletRequest req, HttpServletResponse resp)

throws ServletException, IOException {

String path = getServletContext().getRealPath("/") + "\\upload";

OutputStream o = resp.getOutputStream();

byte b[] = new byte[1024];

//这个地方的文件，可以从数据库中动态查找，我这边写死了为了简单展示

File fileLoad = new File(path, "解析类型配置.xls");

String filename = new String("解析类型配置.xls".getBytes("gbk"), "iso8859-1");

System.out.println(filename);

我记得在Excel导出数据的时候说过filename千万别写中文，其实经过以下：

String filename = new String("解析类型配置.xls".getBytes("gbk"), "iso8859-1");

转换以后，文件无论是中文、英文，都不会出现乱码情况，本人已验证

resp.setHeader("Content-disposition", "attachment;filename="+ filename);

long fileLength = fileLoad.length();

String length = String.valueOf(fileLength);

resp.setHeader("Content_Length", length);

FileInputStream in = new FileInputStream(fileLoad);

int n = 0;

while ((n = in.read(b)) != -1) {

o.write(b, 0, n);

}

}*/

//以上是单个下载附件，这边是批量压缩下载附件

protected void doGet(HttpServletRequest req, HttpServletResponse resp)

throws ServletException, IOException {

String zipFileName = "test.zip";

//这些文件都是存在的，我是写死了的，可以从页面传名称过来

String[] filePathArray = {"1.jpg","2.jpg","3.xls","测试.docx"};

String path = getServletContext().getRealPath("/") + "\\image";

resp.setContentType("application/x-msdownload" ); // 通知客户文件的MIME类型：

resp.setHeader("Content-disposition","attachment;filename=" + zipFileName);

ZipOutputStream zos = new ZipOutputStream(resp.getOutputStream());

for (String filePath : filePathArray) {

File file = new File(path + File.separator + filePath);

doZip(file, zos);

}

zos.close();

}

//处理批量下载时候，文件压缩问题

private void doZip(File file, ZipOutputStream zos) throws IOException {

if(file.exists()) {

if (file.isFile()) {

//如果是文件，写入到 zip 流中

String fileName = file.getName();

ZipEntry zet = new ZipEntry(file.getName());

zos.putNextEntry(zet);

FileInputStream fis = new FileInputStream(file);

byte[] buffer = new byte[1024];

int r = 0;

while ((r = fis.read(buffer)) != -1) {

zos.write(buffer, 0, r);

}

zos.setEncoding("gbk");   //这个地方很重要

zos.flush();

fis.close();

}else {

System.out.println("不是文件，那就不下载了，因为前台会做处理，此处就不在一步步进行验证了!");

}

}

}

}