• 关于springmvc下服务器文件打包成zip格式下载功能


    关于springmvc下服务器文件打包成zip格式下载功能

    版权声明:本文为博主原创文章,未经博主允许不得转载。 https://blog.csdn.net/toxic_guantou/article/details/52605920

    近期,项目要求把服务器存储的上传文件,批量下载到本地.参考网上资料,实现了服务器文件打包成压缩文件然后down到本地功能.
    具体代码实现:
    1、在服务器端创建一个临时zip格式文件
    2、用jdk自带的API将服务器所有文件输入到zip文件中
    3、将zip文件下载到本地,并删除服务器端zip文件

    @RequestMapping(value = "/downloadZip.do")
        public String downloadFiles(String tcLwIds, HttpServletRequest request, HttpServletResponse response)
                throws ServletException, IOException {
            List<File> files = new ArrayList<File>();
            File Allfile = new File(request.getSession().getServletContext().getRealPath("/") + "upload/");
            if (Allfile.exists()) {
                File[] fileArr = Allfile.listFiles();
                for (File file2 : fileArr) {
                    files.add(file2);
                }
            }
    
            String fileName = UUID.randomUUID().toString() + ".zip";
            // 在服务器端创建打包下载的临时文件
            String outFilePath = request.getSession().getServletContext().getRealPath("/") + "upload/";
    
            File fileZip = new File(outFilePath + fileName);
            // 文件输出流
            FileOutputStream outStream = new FileOutputStream(fileZip);
            // 压缩流
            ZipOutputStream toClient = new ZipOutputStream(outStream);
        //  toClient.setEncoding("gbk");
            zipFile(files, toClient);
            toClient.close();
            outStream.close();
            this.downloadFile(fileZip, response, true);
            return null;
        }

    将服务器文件存到压缩包中

    public static void zipFile(List<File> files, ZipOutputStream outputStream) throws IOException, ServletException {
            try {
                int size = files.size();
                // 压缩列表中的文件
                for (int i = 0; i < size; i++) {
                    File file = (File) files.get(i);
                    zipFile(file, outputStream);
                }
            } catch (IOException e) {
                throw e;
            }
        }
    public static void zipFile(File inputFile, ZipOutputStream outputstream) throws IOException, ServletException {
            try {
                if (inputFile.exists()) {
                    if (inputFile.isFile()) {
                        FileInputStream inStream = new FileInputStream(inputFile);
                        BufferedInputStream bInStream = new BufferedInputStream(inStream);
                        ZipEntry entry = new ZipEntry(inputFile.getName());
                        outputstream.putNextEntry(entry);
    
                        final int MAX_BYTE = 10 * 1024 * 1024; // 最大的流为10M
                        long streamTotal = 0; // 接受流的容量
                        int streamNum = 0; // 流需要分开的数量
                        int leaveByte = 0; // 文件剩下的字符数
                        byte[] inOutbyte; // byte数组接受文件的数据
    
                        streamTotal = bInStream.available(); // 通过available方法取得流的最大字符数
                        streamNum = (int) Math.floor(streamTotal / MAX_BYTE); // 取得流文件需要分开的数量
                        leaveByte = (int) streamTotal % MAX_BYTE; // 分开文件之后,剩余的数量
    
                        if (streamNum > 0) {
                            for (int j = 0; j < streamNum; ++j) {
                                inOutbyte = new byte[MAX_BYTE];
                                // 读入流,保存在byte数组
                                bInStream.read(inOutbyte, 0, MAX_BYTE);
                                outputstream.write(inOutbyte, 0, MAX_BYTE); // 写出流
                            }
                        }
                        // 写出剩下的流数据
                        inOutbyte = new byte[leaveByte];
                        bInStream.read(inOutbyte, 0, leaveByte);
                        outputstream.write(inOutbyte);
                        outputstream.closeEntry(); // Closes the current ZIP entry
                        // and positions the stream for
                        // writing the next entry
                        bInStream.close(); // 关闭
                        inStream.close();
                    }
                } else {
                    throw new ServletException("文件不存在!");
                }
            } catch (IOException e) {
                throw e;
            }
        }

    下载文件

     public void downloadFile(File file,HttpServletResponse response,boolean isDelete) {
              try {
                  // 以流的形式下载文件。
                  BufferedInputStream fis = new BufferedInputStream(new FileInputStream(file.getPath()));
                  byte[] buffer = new byte[fis.available()];
                  fis.read(buffer);
                  fis.close();
                  // 清空response
                  response.reset();
                  OutputStream toClient = new BufferedOutputStream(response.getOutputStream());
                  response.setContentType("application/octet-stream");
                  response.setHeader("Content-Disposition", "attachment;filename=" + new String(file.getName().getBytes("UTF-8"),"ISO-8859-1"));
                  toClient.write(buffer);
                  toClient.flush();
                  toClient.close();
                  if(isDelete)
                  {
                      file.delete();        //是否将生成的服务器端文件删除
                  }
               } 
               catch (IOException ex) {
                  ex.printStackTrace();
              }
          } 

    单个文件的下载

    @RequestMapping(value="/singleDownload.do")
        public String singleDownload(String fileName, HttpServletRequest request,
                HttpServletResponse response)throws Exception{
            response.setCharacterEncoding("utf-8");
            response.setContentType("multipart/form-data");
            response.setHeader("Content-Disposition", "attachment;fileName="+ fileName);
            String realPath = request.getSession().getServletContext().getRealPath("/");
            String path = realPath+"upload/";
            File file = new File(path+ File.separator + fileName);
            downloadFile(file, response, false);
            return null;
        }
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  • 原文地址:https://www.cnblogs.com/libin6505/p/9970672.html
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