java servlet这是单个下载，怎么打包批量下载

package cn.szusst.aqms.action.common;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

/**

• Servlet implementation class ServletDownload
  */
  
  @WebServlet(asyncSupported = true, urlPatterns = { "/ServletDownload" })
  
  public class ServletDownload extends HttpServlet {
  
  private static final long serialVersionUID = 1L;

  /**

  • @see HttpServlet#HttpServlet() */
    public ServletDownload() {
    super();
    // TODO Auto-generated constructor stub
    }
    

  /**

  • @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
    */
    
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    
    response.setContentType("application/x-msdownload");
    // TODO Auto-generated method stub

    //获得请求文件名
    
    String filename = request.getParameter("filename");
    
    //设置文件MIME类型

    response.setContentType(getServletContext().getMimeType(filename));
    
    //设置Content-Disposition
    
    response.setHeader("Content-Disposition", "attachment;filename="+filename);
    
    //读取目标文件，通过response将目标文件写到客户端
    
    //获取目标文件的绝对路径
    
    // //读取文件

    OutputStream out = response.getOutputStream();
    
    String fullFileName = filename;
    InputStream in = new FileInputStream(fullFileName);
    
    //写文件
    
    int b;
    
    while((b=in.read())!= -1)
    
    {
    
    out.write(b);
    
    }

    in.close();
    
    // out.close();
    
    }

  /**

  • @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    }
    

}

这是百度上搜的呀

批量文件下载可以利用ZipOutputStream将文件打包，然后输出给客户端。
简单批量下载的工程实例，参考地址：http://download.csdn.net/download/totzc/5772899
批量下载servlet参考代码：

 package servlet;
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;
/**
 * 2013-07-17 22:23:12
 * Servlet 实现多文件下载
 * WeiBo http://weibo.com/totzcc
 * 技术参考文档：
 *      Servlet 实现多文件下载                       http://blog.csdn.net/sunshinestation/article/details/4383953
 *      java.util.zip.ZipOutputStream中文乱码       http://blog.csdn.net/xueyepiaoling/article/details/6119924
 * @author Leo
 *
 */
public class ZipDown extends HttpServlet {

    /**
     * serialVersionUID
     */
    private static final long serialVersionUID = -6442346058533380418L;


    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        //要下载的文件目录
        String path = "D:/sss";
        ZipOutputStream zos = new ZipOutputStream(response.getOutputStream());
        //设置文件编码。 防止中文乱码。 这里用 org.apache.tools.zip.ZipOutputStream; 而不是java.util.zip 下的类
        zos.setEncoding("GBK");
        File file = new File(path);
        makeZip(file, "", zos);
        zos.flush();
        zos.close();
    }


    /**
     *  制作 zip 文件
     * @param file 文件
     * @param baseName 文件根包名
     * @param zos zip 输出流
     * @throws IOException 
     */
    private void makeZip(File file, String baseName, ZipOutputStream zos)
            throws IOException {
        if(file.exists()) {
            if (file.isFile()) {
                //如果是文件，写入到 zip 流中
                zos.putNextEntry(new ZipEntry(baseName + file.getName()));
                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.flush();
                //文件读取完后记得关闭！
                fis.close();
            } else {
                //如果是目录。递归查找里面的文件
                String dirName = baseName + file.getName() + "/";
                zos.putNextEntry(new ZipEntry(dirName));
                File[] subs = file.listFiles();
                for (File f : subs) {
                    makeZip(f, dirName, zos);
                }
            }
        }
    }

}

在慕课网看了视频，搞定