随着互联网的快速发展,大文件的传输成为了互联网应用的重要组成部分。然而,由于网络不稳定等因素的影响,大文件的传输经常会出现中断的情况,这时需要重新传输,导致传输效率低下。
为了解决这个问题,可以实现大文件的断点续传功能。断点续传功能可以在传输中断后继续传输,而不需要从头开始传输。这样可以大大提高传输的效率。
Spring Boot是一个快速开发的Java Web开发框架,可以帮助我们快速搭建一个Web应用程序。在Spring Boot中,我们可以很容易地实现大文件的断点续传功能。
本文将介绍如何使用Spring Boot实现大文件的断点续传功能。
实现大文件的断点续传功能,需要在客户端和服务端都进行相应的实现。
服务端如何将一个大视频文件做切分,分段响应给客户端,让浏览器可以渐进式地播放。
Spring Boot实现HTTP分片下载断点续传,从而实现H5页面的大视频播放问题,实现渐进式播放,每次只播放需要播放的内容就可以了,不需要加载整个文件到内存中。
文件的断点续传、文件多线程并发下载(迅雷就是这么玩的)等。
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cn.hutool -
hutool-bom -
5.8.18 -
pom -
import -
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cn.hutool -
hutool-core -
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org.projectlombok -
lombok -
true -
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- package com.example.insurance.controller;
-
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
-
- import java.io.IOException;
- import java.nio.file.Files;
- import java.nio.file.Path;
- import java.nio.file.Paths;
- import java.util.List;
-
- import com.example.insurance.common.ContentRange;
- import com.example.insurance.common.MediaContentUtil;
- import com.example.insurance.common.NioUtils;
- import lombok.extern.slf4j.Slf4j;
- import org.springframework.http.HttpHeaders;
- import org.springframework.http.HttpRange;
- import org.springframework.http.HttpStatus;
- import org.springframework.util.CollectionUtils;
- import org.springframework.util.StopWatch;
- import org.springframework.web.bind.annotation.GetMapping;
- import org.springframework.web.bind.annotation.PathVariable;
- import org.springframework.web.bind.annotation.RequestHeader;
- import org.springframework.web.bind.annotation.RequestMapping;
- import org.springframework.web.bind.annotation.RestController;
-
- /**
- * 内容资源控制器
- */
- @SuppressWarnings("unused")
- @Slf4j
- @RestController("resourceController")
- @RequestMapping(path = "/resource")
- public class ResourceController {
-
- /**
- * 获取文件内容
- *
- * @param fileName 内容文件名称
- * @param response 响应对象
- */
- @GetMapping("/media/{fileName}")
- public void getMedia(@PathVariable String fileName, HttpServletRequest request, HttpServletResponse response,
- @RequestHeader HttpHeaders headers) {
- // printRequestInfo(fileName, request, headers);
-
- String filePath = MediaContentUtil.filePath();
- try {
- this.download(fileName, filePath, request, response, headers);
- } catch (Exception e) {
- log.error("getMedia error, fileName={}", fileName, e);
- }
- }
-
- /**
- * 获取封面内容
- *
- * @param fileName 内容封面名称
- * @param response 响应对象
- */
- @GetMapping("/cover/{fileName}")
- public void getCover(@PathVariable String fileName, HttpServletRequest request, HttpServletResponse response,
- @RequestHeader HttpHeaders headers) {
- // printRequestInfo(fileName, request, headers);
-
- String filePath = MediaContentUtil.filePath();
- try {
- this.download(fileName, filePath, request, response, headers);
- } catch (Exception e) {
- log.error("getCover error, fileName={}", fileName, e);
- }
- }
-
-
- // ======= internal =======
-
- private static void printRequestInfo(String fileName, HttpServletRequest request, HttpHeaders headers) {
- String requestUri = request.getRequestURI();
- String queryString = request.getQueryString();
- log.debug("file={}, url={}?{}", fileName, requestUri, queryString);
- log.info("headers={}", headers);
- }
-
- /**
- * 设置请求响应状态、头信息、内容类型与长度 等。
- *
- * HTTP/1.1 Range Requests
- * 2. Range Units
- * 4. Responses to a Range Request
- *
- * HTTP/1.1
- * 10.2.7 206 Partial Content
- * 14.5 Accept-Ranges
- * 14.13 Content-Length
- * 14.16 Content-Range
- * 14.17 Content-Type
- * 19.5.1 Content-Disposition
- * 15.5 Content-Disposition Issues
- *
- * Content-Disposition
- * 2. The Content-Disposition Header Field
- * 2.1 The Inline Disposition Type
- * 2.3 The Filename Parameter
- *
- *
- * @param response 请求响应对象
- * @param fileName 请求的文件名称
- * @param contentType 内容类型
- * @param contentRange 内容范围对象
- */
- private static void setResponse(
- HttpServletResponse response, String fileName, String contentType,
- ContentRange contentRange) {
- // http状态码要为206:表示获取部分内容
- response.setStatus(HttpStatus.PARTIAL_CONTENT.value());
- // 支持断点续传,获取部分字节内容
- // Accept-Ranges:bytes,表示支持Range请求
- response.setHeader(HttpHeaders.ACCEPT_RANGES, ContentRange.BYTES_STRING);
- // inline表示浏览器直接使用,attachment表示下载,fileName表示下载的文件名
- response.setHeader(HttpHeaders.CONTENT_DISPOSITION,
- "inline;filename=" + MediaContentUtil.encode(fileName));
- // Content-Range,格式为:[要下载的开始位置]-[结束位置]/[文件总大小]
- // Content-Range: bytes 0-10/3103,格式为bytes 开始-结束/全部
- response.setHeader(HttpHeaders.CONTENT_RANGE, contentRange.toContentRange());
-
- response.setContentType(contentType);
- // Content-Length: 11,本次内容的大小
- response.setContentLengthLong(contentRange.applyAsContentLength());
- }
-
- /**
- * Spring Boot 处理 HTTP Headers
- */
- private void download(
- String fileName, String path, HttpServletRequest request, HttpServletResponse response,
- HttpHeaders headers)
- throws IOException {
- Path filePath = Paths.get(path + fileName);
- if (!Files.exists(filePath)) {
- log.warn("file not exist, filePath={}", filePath);
- return;
- }
- long fileLength = Files.size(filePath);
- // long fileLength2 = filePath.toFile().length() - 1;
- // // fileLength=1184856, fileLength2=1184855
- // log.info("fileLength={}, fileLength2={}", fileLength, fileLength2);
-
- // 内容范围
- ContentRange contentRange = applyAsContentRange(headers, fileLength, request);
-
- // 要下载的长度
- long contentLength = contentRange.applyAsContentLength();
- log.debug("contentRange={}, contentLength={}", contentRange, contentLength);
-
- // 文件类型
- String contentType = request.getServletContext().getMimeType(fileName);
- // mimeType=video/mp4, CONTENT_TYPE=null
- log.debug("mimeType={}, CONTENT_TYPE={}", contentType, request.getContentType());
-
- setResponse(response, fileName, contentType, contentRange);
-
- // 耗时指标统计
- StopWatch stopWatch = new StopWatch("downloadFile");
- stopWatch.start(fileName);
- try {
- // case-1.参考网上他人的实现
- // if (fileLength >= Integer.MAX_VALUE) {
- // NioUtils.copy(filePath, response, contentRange);
- // } else {
- // NioUtils.copyByChannelAndBuffer(filePath, response, contentRange);
- // }
-
- // case-2.使用现成API
- NioUtils.copyByBio(filePath, response, contentRange);
- // NioUtils.copyByNio(filePath, response, contentRange);
-
- // case-3.视频分段渐进式播放
- // if (contentType.startsWith("video")) {
- // NioUtils.copyForBufferSize(filePath, response, contentRange);
- // } else {
- // // 图片、PDF等文件
- // NioUtils.copyByBio(filePath, response, contentRange);
- // }
- } finally {
- stopWatch.stop();
- log.info("download file, fileName={}, time={} ms", fileName, stopWatch.getTotalTimeMillis());
- }
- }
-
- private static ContentRange applyAsContentRange(
- HttpHeaders headers, long fileLength, HttpServletRequest request) {
- /*
- * 3.1. Range - HTTP/1.1 Range Requests
- * https://www.rfc-editor.org/rfc/rfc7233#section-3.1
- * Range: "bytes" "=" first-byte-pos "-" [ last-byte-pos ]
- *
- * For example:
- * bytes=0-
- * bytes=0-499
- */
- // Range:告知服务端,客户端下载该文件想要从指定的位置开始下载
- List
httpRanges = headers.getRange(); -
- String range = request.getHeader(HttpHeaders.RANGE);
- // httpRanges=[], range=null
- // httpRanges=[448135688-], range=bytes=448135688-
- log.debug("httpRanges={}, range={}", httpRanges, range);
-
- // 开始下载位置
- long firstBytePos;
- // 结束下载位置
- long lastBytePos;
- if (CollectionUtils.isEmpty(httpRanges)) {
- firstBytePos = 0;
- lastBytePos = fileLength - 1;
- } else {
- HttpRange httpRange = httpRanges.get(0);
- firstBytePos = httpRange.getRangeStart(fileLength);
- lastBytePos = httpRange.getRangeEnd(fileLength);
- }
- return new ContentRange(firstBytePos, lastBytePos, fileLength);
- }
- }
-
- package com.example.insurance.common;
-
- import javax.servlet.http.HttpServletResponse;
- import java.io.BufferedOutputStream;
- import java.io.InputStream;
- import java.io.OutputStream;
- import java.io.RandomAccessFile;
- import java.nio.MappedByteBuffer;
- import java.nio.channels.Channels;
- import java.nio.channels.FileChannel;
- import java.nio.file.Path;
- import java.nio.file.StandardOpenOption;
-
- import cn.hutool.core.io.IORuntimeException;
- import cn.hutool.core.io.IoUtil;
- import cn.hutool.core.io.NioUtil;
- import cn.hutool.core.io.StreamProgress;
- import cn.hutool.core.io.unit.DataSize;
- import lombok.extern.slf4j.Slf4j;
- import org.apache.catalina.connector.ClientAbortException;
-
- /**
- * NIO相关工具封装,主要针对Channel读写、拷贝等封装
- */
- @Slf4j
- public final class NioUtils {
-
- /**
- * 缓冲区大小 16KB
- *
- * @see NioUtil#DEFAULT_BUFFER_SIZE
- * @see NioUtil#DEFAULT_LARGE_BUFFER_SIZE
- */
- // private static final int BUFFER_SIZE = NioUtil.DEFAULT_MIDDLE_BUFFER_SIZE;
- private static final int BUFFER_SIZE = (int) DataSize.ofKilobytes(16L).toBytes();
-
- /**
- *
- * Java后端实现视频分段渐进式播放
- * 服务端如何将一个大的视频文件做切分,分段响应给客户端,让浏览器可以渐进式地播放。
- * 文件的断点续传、文件多线程并发下载(迅雷就是这么玩的)等。
- *
- * 大文件分片上传前后端实现
- *
- */
- public static void copyForBufferSize(
- Path filePath, HttpServletResponse response, ContentRange contentRange) {
- String fileName = filePath.getFileName().toString();
-
- RandomAccessFile randomAccessFile = null;
- OutputStream outputStream = null;
- try {
- // 随机读文件
- randomAccessFile = new RandomAccessFile(filePath.toFile(), "r");
- // 移动访问指针到指定位置
- randomAccessFile.seek(contentRange.getStart());
-
- // 注意:缓冲区大小 2MB,视频加载正常;1MB时有部分视频加载失败
- int bufferSize = BUFFER_SIZE;
-
- //获取响应的输出流
- outputStream = new BufferedOutputStream(response.getOutputStream(), bufferSize);
-
- // 每次请求只返回1MB的视频流
- byte[] buffer = new byte[bufferSize];
- int len = randomAccessFile.read(buffer);
- //设置此次相应返回的数据长度
- response.setContentLength(len);
- // 将这1MB的视频流响应给客户端
- outputStream.write(buffer, 0, len);
-
- log.info("file download complete, fileName={}, contentRange={}",
- fileName, contentRange.toContentRange());
- } catch (ClientAbortException | IORuntimeException e) {
- // 捕获此异常表示用户停止下载
- log.warn("client stop file download, fileName={}", fileName);
- } catch (Exception e) {
- log.error("file download error, fileName={}", fileName, e);
- } finally {
- IoUtil.close(outputStream);
- IoUtil.close(randomAccessFile);
- }
- }
-
- /**
- * 拷贝流,拷贝后关闭流。
- *
- * @param filePath 源文件路径
- * @param response 请求响应
- * @param contentRange 内容范围
- */
- public static void copyByBio(
- Path filePath, HttpServletResponse response, ContentRange contentRange) {
- String fileName = filePath.getFileName().toString();
-
- InputStream inputStream = null;
- OutputStream outputStream = null;
- try {
- RandomAccessFile randomAccessFile = new RandomAccessFile(filePath.toFile(), "r");
- randomAccessFile.seek(contentRange.getStart());
-
- inputStream = Channels.newInputStream(randomAccessFile.getChannel());
- outputStream = new BufferedOutputStream(response.getOutputStream(), BUFFER_SIZE);
-
- StreamProgress streamProgress = new StreamProgressImpl(fileName);
-
- long transmitted = IoUtil.copy(inputStream, outputStream, BUFFER_SIZE, streamProgress);
- log.info("file download complete, fileName={}, transmitted={}", fileName, transmitted);
- } catch (ClientAbortException | IORuntimeException e) {
- // 捕获此异常表示用户停止下载
- log.warn("client stop file download, fileName={}", fileName);
- } catch (Exception e) {
- log.error("file download error, fileName={}", fileName, e);
- } finally {
- IoUtil.close(outputStream);
- IoUtil.close(inputStream);
- }
- }
-
- /**
- * 拷贝流,拷贝后关闭流。
- *
- * Java NIO 学习笔记(一)----概述,Channel/Buffer
- *
- *
- * @param filePath 源文件路径
- * @param response 请求响应
- * @param contentRange 内容范围
- */
- public static void copyByNio(
- Path filePath, HttpServletResponse response, ContentRange contentRange) {
- String fileName = filePath.getFileName().toString();
-
- InputStream inputStream = null;
- OutputStream outputStream = null;
- try {
- RandomAccessFile randomAccessFile = new RandomAccessFile(filePath.toFile(), "r");
- randomAccessFile.seek(contentRange.getStart());
-
- inputStream = Channels.newInputStream(randomAccessFile.getChannel());
- outputStream = new BufferedOutputStream(response.getOutputStream(), BUFFER_SIZE);
-
- StreamProgress streamProgress = new StreamProgressImpl(fileName);
-
- long transmitted = NioUtil.copyByNIO(inputStream, outputStream,
- BUFFER_SIZE, streamProgress);
- log.info("file download complete, fileName={}, transmitted={}", fileName, transmitted);
- } catch (ClientAbortException | IORuntimeException e) {
- // 捕获此异常表示用户停止下载
- log.warn("client stop file download, fileName={}", fileName);
- } catch (Exception e) {
- log.error("file download error, fileName={}", fileName, e);
- } finally {
- IoUtil.close(outputStream);
- IoUtil.close(inputStream);
- }
- }
-
- /**
- *
- * SpringBoot Java实现Http方式分片下载断点续传+实现H5大视频渐进式播放
- * SpringBoot 实现Http分片下载断点续传,从而实现H5页面的大视频播放问题,实现渐进式播放,每次只播放需要播放的内容就可以了,不需要加载整个文件到内存中。
- * 二、Http分片下载断点续传实现
- * 四、缓存文件定时删除任务
- *
- */
- public static void copy(Path filePath, HttpServletResponse response, ContentRange contentRange) {
- String fileName = filePath.getFileName().toString();
- // 要下载的长度
- long contentLength = contentRange.applyAsContentLength();
-
- BufferedOutputStream outputStream = null;
- RandomAccessFile randomAccessFile = null;
- // 已传送数据大小
- long transmitted = 0;
- try {
- randomAccessFile = new RandomAccessFile(filePath.toFile(), "r");
- randomAccessFile.seek(contentRange.getStart());
- outputStream = new BufferedOutputStream(response.getOutputStream(), BUFFER_SIZE);
- // 把数据读取到缓冲区中
- byte[] buffer = new byte[BUFFER_SIZE];
-
- int len = BUFFER_SIZE;
- //warning:判断是否到了最后不足4096(buffer的length)个byte这个逻辑((transmitted + len) <= contentLength)要放前面
- //不然会会先读取randomAccessFile,造成后面读取位置出错;
- while ((transmitted + len) <= contentLength && (len = randomAccessFile.read(buffer)) != -1) {
- outputStream.write(buffer, 0, len);
- transmitted += len;
-
- log.info("fileName={}, transmitted={}", fileName, transmitted);
- }
- //处理不足buffer.length部分
- if (transmitted < contentLength) {
- len = randomAccessFile.read(buffer, 0, (int) (contentLength - transmitted));
- outputStream.write(buffer, 0, len);
- transmitted += len;
-
- log.info("fileName={}, transmitted={}", fileName, transmitted);
- }
-
- log.info("file download complete, fileName={}, transmitted={}", fileName, transmitted);
- } catch (ClientAbortException e) {
- // 捕获此异常表示用户停止下载
- log.warn("client stop file download, fileName={}, transmitted={}", fileName, transmitted);
- } catch (Exception e) {
- log.error("file download error, fileName={}, transmitted={}", fileName, transmitted, e);
- } finally {
- IoUtil.close(outputStream);
- IoUtil.close(randomAccessFile);
- }
- }
-
- /**
- * 通过数据传输通道和缓冲区读取文件数据。
- *
- * 当文件长度超过{@link Integer#MAX_VALUE}时,
- * 使用{@link FileChannel#map(FileChannel.MapMode, long, long)}报如下异常。
- * java.lang.IllegalArgumentException: Size exceeds Integer.MAX_VALUE
- * at sun.nio.ch.FileChannelImpl.map(FileChannelImpl.java:863)
- * at com.example.insurance.controller.ResourceController.download(ResourceController.java:200)
- *
- *
- * @param filePath 源文件路径
- * @param response 请求响应
- * @param contentRange 内容范围
- */
- public static void copyByChannelAndBuffer(
- Path filePath, HttpServletResponse response, ContentRange contentRange) {
- String fileName = filePath.getFileName().toString();
- // 要下载的长度
- long contentLength = contentRange.applyAsContentLength();
-
- BufferedOutputStream outputStream = null;
- FileChannel inChannel = null;
- // 已传送数据大小
- long transmitted = 0;
- long firstBytePos = contentRange.getStart();
- long fileLength = contentRange.getLength();
- try {
- inChannel = FileChannel.open(filePath, StandardOpenOption.READ, StandardOpenOption.WRITE);
- // 建立直接缓冲区
- MappedByteBuffer inMap = inChannel.map(FileChannel.MapMode.READ_ONLY, firstBytePos, fileLength);
- outputStream = new BufferedOutputStream(response.getOutputStream(), BUFFER_SIZE);
- // 把数据读取到缓冲区中
- byte[] buffer = new byte[BUFFER_SIZE];
-
- int len = BUFFER_SIZE;
- // warning:判断是否到了最后不足4096(buffer的length)个byte这个逻辑((transmitted + len) <= contentLength)要放前面
- // 不然会会先读取file,造成后面读取位置出错
- while ((transmitted + len) <= contentLength) {
- inMap.get(buffer);
- outputStream.write(buffer, 0, len);
- transmitted += len;
-
- log.info("fileName={}, transmitted={}", fileName, transmitted);
- }
- // 处理不足buffer.length部分
- if (transmitted < contentLength) {
- len = (int) (contentLength - transmitted);
- buffer = new byte[len];
- inMap.get(buffer);
- outputStream.write(buffer, 0, len);
- transmitted += len;
-
- log.info("fileName={}, transmitted={}", fileName, transmitted);
- }
-
- log.info("file download complete, fileName={}, transmitted={}", fileName, transmitted);
- } catch (ClientAbortException e) {
- // 捕获此异常表示用户停止下载
- log.warn("client stop file download, fileName={}, transmitted={}", fileName, transmitted);
- } catch (Exception e) {
- log.error("file download error, fileName={}, transmitted={}", fileName, transmitted, e);
- } finally {
- IoUtil.close(outputStream);
- IoUtil.close(inChannel);
- }
- }
-
- }
-
- package com.example.insurance.common;
-
- import lombok.AllArgsConstructor;
- import lombok.Getter;
-
- /**
- * 内容范围对象
- *
- * 4.2. Content-Range - HTTP/1.1 Range Requests
- * Content-Range: "bytes" first-byte-pos "-" last-byte-pos "/" complete-length
- *
- * For example:
- * Content-Range: bytes 0-499/1234
- *
- *
- * @see org.apache.catalina.servlets.DefaultServlet.Range
- */
- @Getter
- @AllArgsConstructor
- public class ContentRange {
-
- /**
- * 第一个字节的位置
- */
- private final long start;
- /**
- * 最后一个字节的位置
- */
- private long end;
- /**
- * 内容完整的长度/总长度
- */
- private final long length;
-
- public static final String BYTES_STRING = "bytes";
-
- /**
- * 组装内容范围的响应头。
- *
- * 4.2. Content-Range - HTTP/1.1 Range Requests
- * Content-Range: "bytes" first-byte-pos "-" last-byte-pos "/" complete-length
- *
- * For example:
- * Content-Range: bytes 0-499/1234
- *
- *
- * @return 内容范围的响应头
- */
- public String toContentRange() {
- return BYTES_STRING + ' ' + start + '-' + end + '/' + length;
- // return "bytes " + start + "-" + end + "/" + length;
- }
-
- /**
- * 计算内容完整的长度/总长度。
- *
- * @return 内容完整的长度/总长度
- */
- public long applyAsContentLength() {
- return end - start + 1;
- }
-
- /**
- * Validate range.
- *
- * @return true if the range is valid, otherwise false
- */
- public boolean validate() {
- if (end >= length) {
- end = length - 1;
- }
- return (start >= 0) && (end >= 0) && (start <= end) && (length > 0);
- }
-
- @Override
- public String toString() {
- return "firstBytePos=" + start +
- ", lastBytePos=" + end +
- ", fileLength=" + length;
- }
- }
-
- package com.example.insurance.common;
-
- import cn.hutool.core.io.StreamProgress;
- import lombok.AllArgsConstructor;
- import lombok.extern.slf4j.Slf4j;
-
- /**
- * 数据流进度条
- */
- @Slf4j
- @AllArgsConstructor
- public class StreamProgressImpl implements StreamProgress {
-
- private final String fileName;
-
- @Override
- public void start() {
- log.info("start progress {}", fileName);
- }
-
- @Override
- public void progress(long total, long progressSize) {
- log.debug("progress {}, total={}, progressSize={}", fileName, total, progressSize);
- }
-
- @Override
- public void finish() {
- log.info("finish progress {}", fileName);
- }
- }
-
- package com.example.insurance.common;
-
- import java.net.URLDecoder;
- import java.net.URLEncoder;
- import java.nio.charset.StandardCharsets;
-
- /**
- * 文件内容辅助方法集
- */
- public final class MediaContentUtil {
-
- public static String filePath() {
- String osName = System.getProperty("os.name");
- String filePath = "/data/files/";
- if (osName.startsWith("Windows")) {
- filePath = "D:\" + filePath;
- }
- // else if (osName.startsWith("Linux")) {
- // filePath = MediaContentConstant.FILE_PATH;
- // }
- else if (osName.startsWith("Mac") || osName.startsWith("Linux")) {
- filePath = "/home/admin" + filePath;
- }
- return filePath;
- }
- public static String encode(String fileName) {
- return URLEncoder.encode(fileName, StandardCharsets.UTF_8);
- }
- public static String decode(String fileName) {
- return URLDecoder.decode(fileName, StandardCharsets.UTF_8);
- }
- }
在客户端中,我们需要实现以下功能:
以下是客户端代码的实现:
- @RestController
- @RequestMapping("/file")
- public class FileController {
- @PostMapping("/upload")
- public ResponseEntity> uploadFile(
- @RequestParam("file") MultipartFile file,
- @RequestParam("fileName") String fileName,
- @RequestParam("startPosition") long startPosition) {
- try { // 建立连接
- Socket socket = new Socket("localhost", 8080);
- OutputStream outputStream = socket.getOutputStream();
- ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
- // 分块传输文件
- FileInputStream fileInputStream = (FileInputStream) file.getInputStream();
- fileInputStream.skip(startPosition);
- byte[] buffer = new byte[1024];
- int len;
- while ((len = fileInputStream.read(buffer)) != -1) {
- outputStream.write(buffer, 0, len);
- }
- // 计算MD5值
- fileInputStream.getChannel().position(0);
- String md5 = DigestUtils.md5Hex(fileInputStream);
- // 与服务端比较MD5值
- InputStream inputStream = socket.getInputStream();
- ObjectInputStream objectInputStream = new ObjectInputStream(inputStream);
- String serverMd5 = (String) objectInputStream.readObject();
- if (!md5.equals(serverMd5)) {
- throw new RuntimeException("MD5值不匹配");
- }
- // 关闭连接
- objectOutputStream.close();
- outputStream.close();
- socket.close();
- } catch (Exception e) {
- e.printStackTrace();
- return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(e.getMessage());
- }
- return ResponseEntity.ok().build();
- }
- }
在服务端中,我们需要实现以下功能:
以下是服务端代码的实现:
- @RestController
- @RequestMapping("/file")
- public class FileController {
- private final String FILE_PATH = "/tmp/upload/";
-
- @PostMapping("/upload")
- public ResponseEntity> uploadFile(HttpServletRequest request, @RequestParam("fileName") String fileName) {
- try {
- // 建立连接
- ServerSocket serverSocket = new ServerSocket(8080);
- Socket socket = serverSocket.accept();
- InputStream inputStream = socket.getInputStream();
- ObjectInputStream objectInputStream = new ObjectInputStream(inputStream);
- // 接收文件
- String filePath = FILE_PATH + fileName;
- RandomAccessFile randomAccessFile = new RandomAccessFile(filePath, "rw");
- long startPosition = randomAccessFile.length();
- randomAccessFile.seek(startPosition);
- byte[] buffer = new byte[1024];
- int len;
- while ((len = inputStream.read(buffer)) != -1) {
- randomAccessFile.write(buffer, 0, len);
- } // 计算MD5值
- FileInputStream fileInputStream = new FileInputStream(filePath);
- String md5 = DigestUtils.md5Hex(fileInputStream);
- // 返回MD5值
- OutputStream outputStream = socket.getOutputStream();
- ObjectOutputStream objectOutputStream = new ObjectOutputStream(outputStream);
- objectOutputStream.writeObject(md5); // 关闭连
- objectInputStream.close();
- inputStream.close();
- randomAccessFile.close();
- socket.close();
- serverSocket.close();
- } catch (Exception e) {
- e.printStackTrace();
- return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body(e.getMessage());
- }
- return ResponseEntity.ok().build();
- }
- }
在前端中,我们需要实现以下功能:
以下是前端代码的实现:
- <html>
- <head>
- <meta charset="UTF-8">
- <title>Spring Boot File Uploadtitle>
- <script src="https://cdn.bootcss.com/jquery/3.3.1/jquery.min.js">script>
- head>
- <body><input type="file" id="file">
- <button onclick="upload()">Uploadbutton>
- <script> var file;
- var startPosition = 0;
- $('#file').on('change', function () {
- file = this.files[0];
- });
-
- function upload() {
- if (!file) {
- alert('Please select a file!');
- return;
- }
- var formData = new FormData();
- formData.append('file', file);
- formData.append('fileName', file.name);
- formData.append('startPosition', startPosition);
- $.ajax({
- url: '/file/upload',
- type: 'post',
- data: formData,
- cache: false,
- processData: false,
- contentType: false,
- success: function () {
- alert('Upload completed!');
- },
- error: function (xhr) {
- alert(xhr.responseText);
- },
- xhr: function () {
- var xhr = $.ajaxSettings.xhr();
- xhr.upload.onprogress = function (e) {
- if (e.lengthComputable) {
- var percent = e.loaded / e.total * 100;
- console.log('Upload percent: ' + percent.toFixed(2) + '%');
- }
- };
- return xhr;
- }
- });
- }script>
- body>
- html>
本文介绍了如何使用Spring Boot实现大文件断点续传。在实现中,我们使用了Java的RandomAccessFile类来实现文件的分块上传和断点续传,使用了Spring Boot的RestController注解来实现Web服务的开发,使用了jQuery的Ajax函数来实现前端页面的开发。
在实际开发中,需要注意以下几点: