//定义下载保存的文件名称
StringBuffer zipName = new StringBuffer(11111.zip);
//从前台接到一个图片id的数组
String[]  images=request.getParameterValues(imgId); 
         System.out.println("imgId============"+imgId);
         DisplayManager dm=new DisplayManager();
         ZipOutputStream zos=null;
         ServletOutputStream sos=null;

         try{
             response.reset();
    response.setContentType("application/x-msdownload"); //通知客户文件的MIME类型：
    //String filename = "default.zip";
    response.setHeader("Content-disposition","attachment;filename=" + zipName.toString());
    sos = response.getOutputStream();
    zos = new ZipOutputStream(sos);

    ZipEntry ze = null;
    byte[] buf = new byte[2048]; //输出文件用的字节数组,每次发送2048个字节到输出流：
    int readLength = 0;
    int z=0;
    String path=request.getSession().getServletContext().getRealPath("img");
    //压缩文件并下载压缩包
    Config con=Config.getInstance();
    System.out.println("images.length=========="+images.length);
    for(int i=0;i<images.length;i++){
//根据id查出该对象
        Display display=dm.selectOne(Long.parseLong(images[i]));
        String imgPath;//给图片路径赋值
         if(Integer.parseInt(display.getType())==1305){
             imgPath="/usr/share/tomcat/webapps/yipai/upload_jinghua/original/"+display.getImage();
         }else{
             imgPath="/usr/share/tomcat/webapps/yipai/upload_yipai/original/"+display.getImage();
         } 
         //String FilePath = images[i];      //list为存放路径的数组 循环可以得到路径和文件名
         File f = new File(imgPath);
       if(!f.exists())
         {
          continue;
         }
       ze = new ZipEntry(display.getImage());
       ze.setSize(f.length());
       ze.setTime(f.lastModified());
       zos.putNextEntry(ze);
       InputStream is = new BufferedInputStream(new FileInputStream(f));
       while ( (readLength = is.read(buf, 0, 2048)) != -1)
       {
         zos.write(buf, 0, readLength);
       }
       //out.clear();  
       //out = pageContext.pushBody();  
       is.close();
     }
    }catch(Exception ex)
    {
        System.out.println("Error download1:"+ex.toString());
    }
    finally
    {
      if(zos!=null){
          try
          {
            zos.close();
          }catch(Exception ex)
          {
             System.out.println("Error download2:"+ex.toString());
          }
        }
    }

public HttpServletResponse download(String path, HttpServletResponse response) {
        try {
            // path是指欲下载的文件的路径。
            File file = new File(path);
            // 取得文件名。
            String filename = file.getName();
            // 取得文件的后缀名。
            String ext = filename.substring(filename.lastIndexOf(".") + 1).toUpperCase();

            // 以流的形式下载文件。
            InputStream fis = new BufferedInputStream(new FileInputStream(path));
            byte[] buffer = new byte[fis.available()];
            fis.read(buffer);
            fis.close();
            // 清空response
            response.reset();
            // 设置response的Header
            response.addHeader("Content-Disposition", "attachment;filename=" + new String(filename.getBytes()));
            response.addHeader("Content-Length", "" + file.length());
            OutputStream toClient = new BufferedOutputStream(response.getOutputStream());
            response.setContentType("application/octet-stream");
            toClient.write(buffer);
            toClient.flush();
            toClient.close();
        } catch (IOException ex) {
            ex.printStackTrace();
        }
        return response;
    }

    public void downloadLocal(HttpServletResponse response) throws FileNotFoundException {
        // 下载本地文件
        String fileName = "Operator.doc".toString(); // 文件的默认保存名
        // 读到流中
        InputStream inStream = new FileInputStream("c:/Operator.doc");// 文件的存放路径
        // 设置输出的格式
        response.reset();
        response.setContentType("bin");
        response.addHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");
        // 循环取出流中的数据
        byte[] b = new byte[100];
        int len;
        try {
            while ((len = inStream.read(b)) > 0)
                response.getOutputStream().write(b, 0, len);
            inStream.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void downloadNet(HttpServletResponse response) throws MalformedURLException {
        // 下载网络文件
        int bytesum = 0;
        int byteread = 0;

        URL url = new URL("windine.blogdriver.com/logo.gif");

        try {
            URLConnection conn = url.openConnection();
            InputStream inStream = conn.getInputStream();
            FileOutputStream fs = new FileOutputStream("c:/abc.gif");

            byte[] buffer = new byte[1204];
            int length;
            while ((byteread = inStream.read(buffer)) != -1) {
                bytesum += byteread;
                System.out.println(bytesum);
                fs.write(buffer, 0, byteread);
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

public void downLoad(String filePath, HttpServletResponse response, boolean isOnLine) throws Exception {
        File f = new File(filePath);
        if (!f.exists()) {
            response.sendError(404, "File not found!");
            return;
        }
        BufferedInputStream br = new BufferedInputStream(new FileInputStream(f));
        byte[] buf = new byte[1024];
        int len = 0;

        response.reset(); // 非常重要
        if (isOnLine) { // 在线打开方式
            URL u = new URL("file:///" + filePath);
            response.setContentType(u.openConnection().getContentType());
            response.setHeader("Content-Disposition", "inline; filename=" + f.getName());
            // 文件名应该编码成UTF-8
        } else { // 纯下载方式
            response.setContentType("application/x-msdownload");
            response.setHeader("Content-Disposition", "attachment; filename=" + f.getName());
        }
        OutputStream out = response.getOutputStream();
        while ((len = br.read(buf)) > 0)
            out.write(buf, 0, len);
        br.close();
        out.close();
    }