java浏览器文件打包下载过程解析

/**   * 图片压缩打包   */  @RequestMapping(value = "/zipFile")  public void compressionFile(HttpServletRequest request, HttpServletResponse response,String busiId) throws Exception{    //业务代码，根据前台传来的ID查询到资源表的图片list    SubMetaData subMetaData = subMetaDataService.findByBusiId(busiId);    if (subMetaData != null) {      List<SubMetaDataAtt> list = subMetaDataAttService.findByDataId(subMetaData.getDataId());      if (list.size() > 0){        subMetaDataAttService.downloadAllFile(request,response,list);      }    }  }

/**   * 将多个文件进行压缩打包，解决文件名下载后的乱码问题   *   */  public void downloadAllFile(HttpServletRequest request, HttpServletResponse response, List<SubMetaDataAtt> list) throws UnsupportedEncodingException{    String downloadName = "附件图片.zip";    String userAgent = request.getHeader("User-Agent");    // 针对IE或者以IE为内核的浏览器：    if (userAgent.contains("MSIE") || userAgent.contains("Trident")) {      downloadName = java.net.URLEncoder.encode(downloadName, "UTF-8");    } else {      // 非IE浏览器的处理：      downloadName = new String(downloadName.getBytes("UTF-8"), "ISO-8859-1");    }//经过上面的名称处理即可解决文件名下载后乱码的问题    response.setContentType("multipart/form-data");    response.setCharacterEncoding("UTF-8");    response.setHeader("Content-Disposition", String.format("attachment; filename=/"%s/"", downloadName));    //response.setHeader("Content-Disposition", "attachment;fileName=" + downloadName);    OutputStream outputStream = null;    ZipOutputStream zos = null;    try {      outputStream = response.getOutputStream();      zos = new ZipOutputStream(outputStream);      // 将文件流写入zip中，此方法在下面贴出      downloadTolocal(zos,list);    } catch (IOException e) {      logger.error("downloadAllFile-下载全部附件失败",e);    }finally {      if(zos != null) {        try {          zos.close();        } catch (Exception e2) {          logger.info("关闭输入流时出现错误",e2);        }      }      if(outputStream != null) {        try {          outputStream.close();        } catch (Exception e2) {          logger.info("关闭输入流时出现错误",e2);        }      }    }  }

private void downloadTolocal(ZipOutputStream zos, List<SubMetaDataAtt> list) throws IOException {    //获取文件信息//此处为业务代码，可根据自己的需要替换,我在这里是将资源表list循环出取得路径以及文件名，然后放进ZipEntry中再执行下载。    for (SubMetaDataAtt subMetaDataAtt : list) {      String fileId = subMetaDataAtt.getAttId();      String fileName = subMetaDataAtt.getFileAlias()+subMetaDataAtt.getFileSuffixName();      String path = subMetaDataAtt.getFileAbsolutePath();      InputStream is = null;      BufferedInputStream in = null;      byte[] buffer = new byte[1024];      int len;      //创建zip实体（一个文件对应一个ZipEntry）      ZipEntry entry = new ZipEntry(fileName);      try {        //获取需要下载的文件流        File file= new File(path);        if(file.exists()){          is = new FileInputStream(file);        }        in = new BufferedInputStream(is);        zos.putNextEntry(entry);        //文件流循环写入ZipOutputStream        while ((len = in.read(buffer)) != -1 ) {          zos.write(buffer, 0, len);        }      } catch (Exception e) {        logger.info("下载全部附件--压缩文件出错",e);      }finally {        if(entry != null) {          try {            zos.closeEntry();          } catch (Exception e2) {            logger.info("下载全部附件--zip实体关闭失败",e2);          }        }        if(in != null) {          try {            in.close();          } catch (Exception e2) {            logger.info("下载全部附件--文件输入流关闭失败",e2);          }        }        if(is != null) {          try {            is.close();          }catch (Exception e) {            logger.info("下载全部附件--输入缓冲流关闭失败",e);          }        }      }    }

window.open(context+"/sub/submetadataatt/zipFile?busiId="+downloadId);//这里的downloadId是我需要传到后台的变量。