分片上传本质就是在前端把一个完整的文件拆分成若干份文件上传，上传完成后，服务器再把上传的若干份文件合并成一个完整的文件，再删除若干份分片文件。
首先导包
org.springframework.boot
spring-boot-starter-web
mysql
mysql-connector-java
tk.mybatis
mapper-spring-boot-starter
2.1.5
com.alibaba
fastjson
1.2.79
org.projectlombok
lombok
1.18.22
application.yml配置：
server:
port: 8080
servlet:
context-path: /test
tomcat:
max-http-form-post-size: -1
spring:
datasource:
name: DS #如果存在多个数据源，监控的时候可以通过名字来区分开来。如果没有配置，将会生成一个名字，格式是："DataSource-" + System.identityHashCode(this)
type: com.zaxxer.hikari.HikariDataSource
url: jdbc:mysql://127.0.0.1:3306/upload?useUnicode=true&characterEncoding=UTF-8&allowMultiQueries=true&useSSL=false&serverTimezone=GMT
#hikari相关配置
hikari:
driver-class-name: com.mysql.cj.jdbc.Driver
username: root
password: 123456
servlet:
multipart:
max-file-size: 50MB
max-request-size: 50MB
# mybatis配置
mybatis:
type-aliases-package: com.upload.pojo
# mapper-locations: classpath:mapper/*.xml
configuration:
map-underscore-to-camel-case: true
cache-enabled: true #使全局的映射器启用或禁用缓存。
lazy-loading-enabled: true #全局启用或禁用延迟加载。当禁用时，所有关联对象都会即时加载。
aggressive-lazy-loading: true #当启用时，有延迟加载属性的对象在被调用时将会完全加载任意属性。否则，每种属性将会按需要加载。
jdbc-type-for-null: null #设置但JDBC类型为空时,某些驱动程序 要指定值,default:OTHER，插入空值时不需要指定类型
logging:
level:
com.upload.dao: debug
再数据库建一张表 file
CREATE TABLE `file` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`path` varchar(255) NOT NULL DEFAULT '' COMMENT '文件路径',
`name` varchar(255) NOT NULL DEFAULT '' COMMENT '文件名称',
`size` bigint(20) unsigned NOT NULL DEFAULT '0' COMMENT '文件大小',
`suffix` varchar(10) NOT NULL DEFAULT '' COMMENT '后缀',
`type` varchar(10) NOT NULL DEFAULT '' COMMENT '文件类型',
`share_total` int(10) unsigned NOT NULL DEFAULT '0' COMMENT '文件分片总数',
`share_index` int(10) unsigned NOT NULL DEFAULT '0' COMMENT '已上传分片索引,默认0',
`key` varchar(32) NOT NULL DEFAULT '' COMMENT '文件唯一Key',
`create_time` datetime DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP,
`update_time` datetime DEFAULT NULL ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (`id`),
UNIQUE KEY `key` (`key`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8mb4 COMMENT='文件分片上传表';
创建对应实体类 FilePojo：
package com.upload.pojo;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;
import javax.persistence.Column;
import javax.persistence.Id;
import javax.persistence.Table;
import java.io.Serializable;
import java.util.Date;
/**
* @author xiaochi
* @date 2022/3/14 22:52
* @desc FilePojo
*/
@Data
@Builder
@NoArgsConstructor
@AllArgsConstructor
@Table(name = "file")
public class FilePojo implements Serializable {
private static final long serialVersionUID = -6334172193008858856L;
@Id
private Integer id;
private String path;
private String name;
private Long size;
private String suffix;
@Column(name = "`type`")
private String type;
private Integer shareTotal;
private Integer shareIndex;
@Column(name = "`key`")
private String key;
private Date createTime;
private Date updateTime;
}
接着再创建一个接收前端参数的Vo文件 FileVo
package com.upload.vo;
import com.upload.pojo.FilePojo;
import lombok.Data;
import lombok.EqualsAndHashCode;
import org.springframework.web.multipart.MultipartFile;
/**
* @author xiaochi
* @date 2022/3/15 8:38
* @desc FileVo
*/
@Data
@EqualsAndHashCode(callSuper = true)
public class FileVo extends FilePojo {
private static final long serialVersionUID = -4528742454491886780L;
private MultipartFile file;
}
FileVo拥有 FilePojo 的所有属性。接着创建一个 FileDao文件
/**
* @author xiaochi
* @date 2022/3/14 22:56
* @desc FileDao
*/
public interface FileDao extends Mapper, MySqlMapper {
}
接着创建控制器 UploadController
package com.upload.controller;
import com.upload.common.R;
import com.upload.dao.FileDao;
import com.upload.pojo.FilePojo;
import com.upload.vo.FileVo;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import tk.mybatis.mapper.entity.Example;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;
/**
* @author xiaochi
* @date 2022/3/14 22:08
* @desc UploadController
*/
@Slf4j
@CrossOrigin("*")
@RestController
@RequestMapping("/file")
public class UploadController {
private static final String FILE_PATH = "d:/upload/";
@Autowired
private FileDao fileDao;
/**
* 根据文件唯一key判断是否有上传
* @param key
* @return
*/
@GetMapping("/check/{key}")
public R check(@PathVariable String key){
return R.ok(findByKey(key));
}
/**
* 分片上传（表单接收）
* @param fileVo
* @return
* @throws Exception
*/
@PostMapping(value = "/upload")
// public R upload(@RequestBody @RequestParam("file") MultipartFile file) throws IOException {
public R upload(FileVo fileVo) throws Exception {// 表单接收
MultipartFile file = fileVo.getFile();
String filename = file.getOriginalFilename();
String date = new SimpleDateFormat("yyyy/MM/dd").format(new Date());
String localPath = new StringBuilder()
.append(date)
.append(File.separator)
.append(fileVo.getName())
.append(".")
.append(fileVo.getShareIndex())
.toString();// 分片文件路径与后缀处理 2022/03/15\13-提交Git仓库.mp4.0 、2022/03/15\13-提交Git仓库.mp4.1、2022/03/15\13-提交Git仓库.mp4.2 .....
fileVo.setPath(localPath);
File dest = new File(FILE_PATH + localPath);
if (!dest.getParentFile().exists()){
dest.getParentFile().setWritable(true);
dest.getParentFile().mkdirs();// 不加 getParentFile() 创建的是文件夹，不是文件
}
file.transferTo(dest);
FilePojo filePojo = new FilePojo();
BeanUtils.copyProperties(fileVo,filePojo);
String path = new StringBuilder()
.append(date)
.append(File.separator)
.append(fileVo.getName())
.toString();// 数据库保存的最后完整文件的路径与名称， 2022/03/15\13-提交Git仓库.mp4
filePojo.setPath(path);
// 查询之前是否有过上传
Example example = new Example(FilePojo.class);
Example.Criteria criteria = example.createCriteria();
criteria.andEqualTo("key",filePojo.getKey());
FilePojo filePojoDb = fileDao.selectOneByExample(example);
if (filePojoDb == null){
fileDao.insertSelective(filePojo);
}else {
fileDao.updateByExampleSelective(filePojo,example);
}
// 判断是否上传玩最后一个分片文件，然后进行合并完整文件并删除所有分片文件
if (fileVo.getShareIndex().equals(fileVo.getShareTotal()-1)){
this.merge(filePojo);
}
return R.ok(path);
}
/**
* 合并所有分片文件成功后并删除所有分片文件
* @param filePojo
* @throws Exception
*/
private void merge(FilePojo filePojo) throws Exception {
String path = FILE_PATH + filePojo.getPath();
//FileOutputStream outputStream = new FileOutputStream(new File(path), true);// true表示可追加
BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(new File(path), true));
//FileInputStream inputStream = null;
BufferedInputStream bis = null;
byte[] byt = new byte[10* 1024 * 1024];
int len;
try {
for (int i = 0,leng = filePojo.getShareTotal(); i < leng; i++) {
// 从第i个分片读取
/*inputStream = new FileInputStream(new File(path + "." + i));//
while ((len = inputStream.read(byt)) != -1){
outputStream.write(byt,0,len);
}*/
bis = new BufferedInputStream(new FileInputStream(new File(path + "." + i)));
while ((len = bis.read(byt))!= -1){
bos.write(byt,0,len);
}
}
}catch (IOException e){
log.error("分片合并异常", e);
}finally {
/*try {
if (inputStream != null){
inputStream.close();
}
outputStream.close();
}catch (Exception e){
log.error("IO流关闭异常", e);
}*/
bos.flush();
bos.close();
if (bis != null){
bis.close();
}
}
// 删除分片文件
System.gc();
Thread.sleep(100);
for (int i = 0,leng = filePojo.getShareTotal(); i < leng; i++) {
String localPath = path + "." + i;
File file = new File(localPath);
if (file.exists()){
boolean result = file.delete();
log.info("删除分片文件{}，{}", localPath, result ? "成功" : "失败");
}
}
}
/**
* 根据文件唯一key查询
* @param key
* @return
*/
private FilePojo findByKey(String key){
Example example = new Example(FilePojo.class);
Example.Criteria criteria = example.createCriteria();
criteria.andEqualTo("key",key);
return fileDao.selectOneByExample(example);
}
}
然后前端对应的请求代码：
Title
上传：
到此完成，但是这里后台接口没有做文件完整性验证，如要进行完整性验证，请看下面
文件完整性验证上传
要进行文件完整性验证就不能直接 MultipartFile接收了，要在前端吧文件转成 Base64 进行上传了，然后后台接收后解析成 MultipartFile
首先，FileVo文件要修改下
package com.upload.vo;
import com.upload.pojo.FilePojo;
import lombok.Data;
import lombok.EqualsAndHashCode;
import org.springframework.web.multipart.MultipartFile;
/**
* @author xiaochi
* @date 2022/3/15 8:38
* @desc FileVo
*/
@Data
@EqualsAndHashCode(callSuper = true)
public class FileVo extends FilePojo {
private static final long serialVersionUID = -4528742454491886780L;
private String file;// base64文件字符串
private String encryFile;// 前端进行md5加密后的符
}
接着新建一个文件 Base64DecodeMultipartFile 用来将接收到的Base64字符串转成 MultipartFile
package com.upload.util;
import org.springframework.web.multipart.MultipartFile;
import sun.misc.BASE64Decoder;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
/** base64转为multipartFile
* @author xiaochi
* @date 2022/4/11 15:30
* @desc Base64DecodeMultipartFile
*/
public class Base64DecodeMultipartFile implements MultipartFile {
private final byte[] imgContent;
private final String header;
public Base64DecodeMultipartFile(byte[] imgContent, String header) {
this.imgContent = imgContent;
this.header = header.split(";")[0];
}
@Override
public String getName() {
return System.currentTimeMillis() + Math.random() + "." + header.split("/")[1];
}
@Override
public String getOriginalFilename() {
return System.currentTimeMillis() + (int) Math.random() * 10000 + "." + header.split("/")[1];
}
@Override
public String getContentType() {
return header.split(":")[1];
}
@Override
public boolean isEmpty() {
return imgContent == null || imgContent.length == 0;
}
@Override
public long getSize() {
return imgContent.length;
}
@Override
public byte[] getBytes() throws IOException {
return imgContent;
}
@Override
public InputStream getInputStream() throws IOException {
return new ByteArrayInputStream(imgContent);
}
@Override
public void transferTo(File dest) throws IOException, IllegalStateException {
new FileOutputStream(dest).write(imgContent);
}
/**
* * base64转multipartFile
* * @param base64
* * @return
*/
public static MultipartFile base64Convert(String base64) {
String[] baseStrs = base64.split(",");
BASE64Decoder decoder = new BASE64Decoder();
byte[] b = new byte[0];
try {
b = decoder.decodeBuffer(baseStrs[1]);
} catch (IOException e) {
e.printStackTrace();
}
for (int i = 0; i < b.length; ++i) {
if (b[i] < 0) {
b[i] += 256;
}
}
return new Base64DecodeMultipartFile(b, baseStrs[0]);
}
}
接着修改上传文件的接口控制器方法 UploadController的上传方法 upload
/**
* 分片上传（表单接收），且进行文件完整性验证
* @param fileVo
* @return
* @throws Exception
*/
@PostMapping("/upload")
public R upload(FileVo fileVo) throws Exception {
MultipartFile file = Base64DecodeMultipartFile.base64Convert(fileVo.getFile());// 将 Base64 字符串解析成 MultipartFile
// 验证文件完整性
if (!Objects.equals(fileVo.getEncryFile(),DigestUtils.md5DigestAsHex(fileVo.getFile().getBytes()))){
return R.error("上传文件已被损坏");
}
String date = new SimpleDateFormat("yyyy/MM/dd").format(new Date());
String localPath = new StringBuilder()
.append(date)
.append(File.separator)
.append(fileVo.getName())
.append(".")
.append(fileVo.getShareIndex())
.toString();// 分片文件路径与后缀处理 2022/03/15\13-提交Git仓库.mp4.0 、2022/03/15\13-提交Git仓库.mp4.1、2022/03/15\13-提交Git仓库.mp4.2 .....
fileVo.setPath(localPath);
File dest = new File(FILE_PATH + localPath);
if (!dest.getParentFile().exists()){
dest.getParentFile().setWritable(true);
dest.getParentFile().mkdirs();// 不加 getParentFile() 创建的是文件夹，不是文件
}
file.transferTo(dest);
FilePojo filePojo = new FilePojo();
BeanUtils.copyProperties(fileVo,filePojo);
String path = new StringBuilder()
.append(date)
.append(File.separator)
.append(fileVo.getName())
.toString();// 数据库保存的最后完整文件的路径与名称， 2022/03/15\13-提交Git仓库.mp4
filePojo.setPath(path);
// 查询之前是否有过上传
Example example = new Example(FilePojo.class);
Example.Criteria criteria = example.createCriteria();
criteria.andEqualTo("key",filePojo.getKey());
FilePojo filePojoDb = fileDao.selectOneByExample(example);
if (filePojoDb == null){
fileDao.insertSelective(filePojo);
}else {
fileDao.updateByExampleSelective(filePojo,example);
}
// 判断是否上传玩最后一个分片文件，然后进行合并完整文件并删除所有分片文件
if (fileVo.getShareIndex().equals(fileVo.getShareTotal()-1)){
this.merge(filePojo);
}
return R.ok(path);
}
接着修改对应的前端代码
Title
上传：
然后运行上传完整，ok，到此结束。