文件上传、下载、合并、分片、删除

2023-11-07 22:27| 来源: 网络整理| 查看: 265

文件上传、下载、合并、分片、删除 Controller层Service层使用了Hutool工具类库

Controller层

除了 MultipartFile 其他参数可以忽视

/** * 前端上传文件 * * @param file * @param proxyId * @return * @throws IOException */ @PostMapping("/upload") public Result fileUpload(@RequestParam("file")MultipartFile file, String proxyId) throws IOException { fileListService.upload(file, proxyId); return Result.success(); } /** * 前端下载文件 * * @param proxyId * @param name * @return * @throws IOException */ @GetMapping("/download") public Result download(@RequestParam("proxyId") String proxyId, @RequestParam("name") String name, String size, HttpServletResponse response) throws IOException { return fileListService.download(proxyId, name, size, response) ? Result.success("下载成功") : Result.failed("下载失败，请检查文件目录"); } Service层

上传文件

public void upload(MultipartFile multipartFile, String proxyId) throws IOException { //文件夹路径 String folder = MqttConstants.FILE_PATH_OUTPUT + "/" + proxyId; File dist = new File(folder); if (!dist.isDirectory()) { //文件夹不存在 --> 创建文件夹 dist.mkdirs(); } //文件夹 + 文件名(带后缀) File file = new File(folder + "/" + multipartFile.getOriginalFilename()); multipartFile.transferTo(file); }

下载文件，这里包含了已分片文件合并成整个文件和删除文件操作

// 下载文件 --> 去OUTPUT目录查看是否有这个文件 // 无 --> 去INPUT目录查找目录，将文件分片合并成一个文件，到OUTPUT目录，并删除INPUT目录下的分片文件 // 有 --> 去OUTPUT目录下载文件 public boolean download(String proxyId, String name, String size, HttpServletResponse response) throws IOException { //1、判断是否存在这个文件 // output/proxyId/name File folder = new File(MqttConstants.FILE_PATH_OUTPUT + "/" + proxyId + "/" + name); log.info("去目录判断是否存在:" + MqttConstants.FILE_PATH_OUTPUT + "/" + proxyId + "/" + name); //文件不存在去合并文件 if (!folder.exists()) { log.info( "文件不存在,去合并文件,合并目录内的文件:" + MqttConstants.FILE_PATH_INPUT + "/" + proxyId + "/" + name + "/"); File input = new File(MqttConstants.FILE_PATH_INPUT + "/" + proxyId + "/" + name + "/"); if (!input.exists()) { log.info("=============合并目录不存在============="); return false; } else { FilterByText filter = new FilterByText(name); String[] list = input.list(filter); assert list != null; byte[] bytes = new byte[Integer.parseInt(size)]; int length = list.length; System.out.println("文件个数:" + length); BufferedOutputStream bufferedOutput = null; if (list.length != 0) { int count = 0; TimeInterval timer = DateUtil.timer(); for (String str : list) { //#& --> 接收文件分片后重新命名文件,作为标识符的 int i = Integer.parseInt(str.split("#&")[0]); File file = new File(input + "/" + str); count++; FileReader reader = new FileReader(file); byte[] bb = reader.readBytes(); System.arraycopy(bb, 0, bytes, (i - 1) * 2, bb.length); File outFile = new File(MqttConstants.FILE_PATH_OUTPUT + "/" + proxyId); if (!outFile.exists()) { outFile.mkdirs(); } File out = new File(MqttConstants.FILE_PATH_OUTPUT + "/" + proxyId + "/" + name); OutputStream output = new FileOutputStream(out); bufferedOutput = new BufferedOutputStream(output); bufferedOutput.write(bytes); } bufferedOutput.close(); log.info("文件总个数:" + length + "个,合并了" + count + "个文件,共耗时" + timer.intervalSecond() + "秒"); } //删除文件目录以及目录内容 deleteDir(input); } } response.setHeader("Content-disposition", "attachment;filename=" + name); //拿到需要下载的文件 File file = new File(MqttConstants.FILE_PATH_OUTPUT + "/" + proxyId + "/" + name); //file转byte[] FileReader reader = new FileReader(file); byte[] bb = reader.readBytes(); //文件大小 response.addHeader("Content-Length", "" + file.length()); ServletOutputStream outputStream = response.getOutputStream(); outputStream.write(bb); outputStream.close(); return true; } /** * 递归删除目录下的所有文件及子目录下所有文件 * * @param dir 将要删除的文件目录 * @return boolean Returns "true" if all deletions were successful. If a deletion fails, the * method stops attempting to delete and returns "false". */ private static boolean deleteDir(File dir) { if (dir.isDirectory()) { String[] children = dir.list(); //递归删除目录中的子目录下 for (int i = 0; i return false; } } } // 目录此时为空，可以删除 return dir.delete(); }

文件分片这里将文件分片后转成Base64通过MQTT发了出去

public Boolean setFile(String proxyId, String name) throws IOException, InterruptedException { String folder = MqttConstants.FILE_PATH_OUTPUT + "/" + proxyId; File dist = new File(folder); if (!dist.isDirectory()) { return false; } //读取文件 File file = new File(folder + "/" + name); FileReader reader = new FileReader(file); BufferedInputStream inputStream = reader.getInputStream(); //file转byte[] byte[] bytes = reader.readBytes(); int length = bytes.length; //这里是具体的业务逻辑了可以忽视 MqttMsg mqttMsg = new MqttMsg(); mqttMsg.setServiceId(proxyId); mqttMsg.setClientId(MqttConstants.EMP); mqttMsg.setDirection(MqttConstants.DIRECTION_REQUEST); mqttMsg.setVersion(MqttConstants.VERSION_V1); mqttMsg.setDeviceId("xx"); mqttMsg.setMId("xx"); mqttMsg.setTimestamp("xx"); mqttMsg.setExpire("xx"); mqttMsg.setType(TopicType.SET_FILE); //字节小于10KB 不需要分片 //这里可以根据自己的分片需要定义 if (bytes.length //字节大于 10KB 情况1整除情况2非整除,有余数 int yu = length % 10240; int split = length / 10240; byte[] bb = new byte[10240]; //非整除，有余数最后一片小于10KB 需特殊处理 if (yu != 0) { for (int i = 0; i bb = new byte[i]; inputStream.read(bb, 0, i); } else { //每片 10KB inputStream.read(bb, 0, 10240); } String base64 = Base64.getEncoder().encodeToString(bb); JSONObject object = new JSONObject(); object.put("name", name); object.put("total", String.valueOf(split)); object.put("size", String.valueOf(length)); object.put("current", String.valueOf(i)); object.put("data", base64); mqttMsg.setParams(object); mqttPublishService.publishRequest(mqttMsg, MqttConstants.QOS_1); //避免丢包延时2ms Thread.sleep(2); } } else { //整除 for (int i = 0; i

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