java实现文件的断点续传和断点下载，有知道的交流下。

Posted 2023-03-21

java实现文件的断点续传和断点下载，有知道的交流下。

参考技术A

/**      * 下载服务器已存在的文件      *       * @param request      * @param response      * @param proposeFile      * @throws IOException      * @throws FileNotFoundException      */      private void downloadExistsFile(HttpServletRequest request,              HttpServletResponse response, File proposeFile) throws IOException,              FileNotFoundException           log.debug("下载文件路径：" + proposeFile.getPath());          long fSize = proposeFile.length();          // 下载          response.setContentType("application/x-download");          String isoFileName = this                  .encodeFilename(proposeFile.getName(), request);          response.setHeader("Accept-Ranges", "bytes");          response.setHeader("Content-Length", String.valueOf(fSize));          response.setHeader("Content-Disposition", "attachment; filename="                  + isoFileName);          long pos = 0;          if (null != request.getHeader("Range"))               // 断点续传              response.setStatus(HttpServletResponse.SC_PARTIAL_CONTENT);              try                   pos = Long.parseLong(request.getHeader("Range").replaceAll(                          "bytes=", "").replaceAll("-", ""));               catch (NumberFormatException e)                   log.error(request.getHeader("Range") + " is not Number!");                  pos = 0;                                  ServletOutputStream out = response.getOutputStream();          BufferedOutputStream bufferOut = new BufferedOutputStream(out);          InputStream inputStream = new FileInputStream(proposeFile);          String contentRange = new StringBuffer("bytes ").append(                  new Long(pos).toString()).append("-").append(                  new Long(fSize - 1).toString()).append("/").append(                  new Long(fSize).toString()).toString();          response.setHeader("Content-Range", contentRange);          log.debug("Content-Range", contentRange);          inputStream.skip(pos);          byte[] buffer = new byte[5 * 1024];          int length = 0;          while ((length = inputStream.read(buffer, 0, buffer.length)) != -1)               bufferOut.write(buffer, 0, length);                    bufferOut.flush();          bufferOut.close();          out.close();          inputStream.close();        

追问

你这个好像是断点下载的，上传的有吗

参考技术B

我项目中用到的关键代码，断点下载文件：

URL url = new URL("http://f1.market.xiaomi.com/download/AppStore/0279e54e42c95454b29ac9628eccb1bfb5be22aeb/dian.zi.com.zidian.apk");

HttpURLConnection httpConnection = (HttpURLConnection) url.openConnection();

httpConnection.setRequestProperty("User-Agent", "NetFox");

httpConnection.setReadTimeout(60000);

//xxx表示你已下载的文件大小

httpConnection.setRequestProperty("RANGE", "bytes=" + xxx + "-");