客户端打包下载七牛图片

获取七牛图片URL，使用流来下载图片
一、工具类

package com.bayan.keke.util;import net.sf.json.JSONObject;import java.io.*;import java.net.URL;import java.net.URLConnection;import java.util.List;import java.util.Map;import java.util.zip.ZipEntry;import java.util.zip.ZipOutputStream;    /**     * @param sourceUrls :待压缩的文件路径(Map:key="imgName",key="imgUrl")     * @param zos :压缩后的输出流     * *@param fileName :压缩后文件的名称     * @return     * */    public static boolean downloadToZip(List<Map<String,String>> sourceUrls,ZipOutputStream zos){        boolean flag = false;        //输入        InputStream fis = null;        BufferedInputStream bis = null;        try {            // 10K的数据缓冲            byte[] bufs = new byte[1024*10];            for(Map<String,String> sourceUrl : sourceUrls){                //fileName                //String imgName= DateUtil.getStringByFormat(System.currentTimeMillis(),DateUtil.dateFormatYMDHMS);                String imgName = sourceUrl.get("imgName");                // 构造URL                URL url = new URL(sourceUrl.get("imgUrl"));                // 打开连接                URLConnection con = url.openConnection();                //设置请求超时为5s                con.setConnectTimeout(5 * 1000);                //读取待压缩的文件并写进压缩包里                fis = con.getInputStream();                bis = new BufferedInputStream(fis, 1024*10);                //创建ZIP实体，并添加进压缩包                ZipEntry zipEntry = new ZipEntry(imgName +".jpg");                zos.putNextEntry(zipEntry);                int read = 0;                while((read=bis.read(bufs, 0, 1024*10)) != -1){                    zos.write(bufs,0,read);                }            }            flag = true;        } catch (FileNotFoundException e) {            e.printStackTrace();        }catch (IOException e) {            System.out.println("连接中断！");            e.printStackTrace();        }finally {            //关闭流            try {                if(null != bis) bis.close();                if(null != zos) zos.close();                if(null != fis) fis.close();            } catch (IOException e) {                e.printStackTrace();                throw new RuntimeException(e);            }        }        return flag;    }}

二、action

public void downTasksToZip(){        int taskResult = 0;        try {            String param = getRequest().getParameter("result");            if( param != null ){                taskResult = Integer.parseInt(param);            }            // 设置响应头，控制浏览器下载该文件            getResponse().setHeader("content-disposition","attachment;filename=" + URLEncoder.encode("图片.zip", "UTF-8"));            // 创建输出流            OutputStream outputStream = getResponse().getOutputStream();            ZipOutputStream zos = new ZipOutputStream(outputStream);            //获取所有图片url            List<Map<String,String>> list = imageService.getImageUrl(taskResult);            if( list.size() > 0){                boolean rst = DownLoadUtil.downloadToZip(list,zos);            }            // 请求结束log            outputStream.close();        } catch (Exception e) {            printSysErr(e, logger);        }    }

三、拼接图片url

使用时间戳防盗链，这里不再细说，具体可参考上一篇博客

    /**     *获取所有被推荐作业的url     */    public List<Map<String,String>> getImageUrl(Integer type)throws Exception{        List<Map<String,String>> list = new ArrayList<>();        List<String > photoUrls = iamgeDao.getImageUrl(type);        for(String s: photoUrls){            Map map = new HashMap();            String[] strings = s.split("/");            map.put("imgName",strings[strings.length -1]);            map.put("imgUrl",Common.getUrlSign(s));            list.add(map);        }        return list;    }