我们在工作中可能会遇到大文件的上传，如果一次传输，很有可能会遇到 网络、超时各种各样的问题。这里将分片上传和断点续传两种方式介绍一下方案。

一、分片上传

分片上传的原理：前端首先请求接口获取这次上传的uuid,上传的时间等信息返回给前端页面。前端将所要上传文件进行分片，在上传的时候包含 服务器返回给前端的 该次上传的uuid，该篇文件的md5，上传的第几片的的标识，和文件名称等标识。等到上传的片数等于总片数的时候对所有分片进行合并，删除临时分片。

这里由springboot+freemarker 来演示这个原理
(服务端用到工具类和前端用到的 js由于断点续传 同样也用到，在介绍完 断点续传 之后统一贴出来)

1、首先添加配置文件 application.properties（由于断点续传 需要依赖mysql故也将mysql引入）

server.port=8080spring.freemarker.expose-spring-macro-helpers=true
# 是否优先从文件系统加载template，以支持热加载，默认为true
spring.freemarker.prefer-file-system-access=true
# 设定模板的后缀.
spring.freemarker.suffix=.ftl
# 设定模板的加载路径，多个以逗号分隔，默认:
spring.freemarker.template-loader-path=classpath:/templates/
spring.mvc.static-path-pattern=/static/**spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/pingyougou
spring.datasource.username=root
spring.datasource.password=root#配置.xml文件路径
mybatis.config-locations=classpath:mybatis/mybatis-config.xml
mybatis.mapper-locations=classpath:conf/mapper/*Mapper.xml
#配置模型路径
mybatis.type-aliases-package=com.yin.freemakeradd.pojo

2、引入controller类

localhost:8080/upload2/index 第断点上传入口

@Controller
@RequestMapping(value = "/test")
public class IndexController {@GetMapping(value = "/upload/index")public String  index(Model model){return "breakpointBurst";}@GetMapping(value = "/upload2/index")public String  index2(Model model){return "burst";}}

分片上传的具体上传逻辑

@RestController
@RequestMapping(value = "/burst/test")
public class BurstController {private static final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMdd");private static final String temp_dir = "C:\\Users\\Administrator\\Desktop\\upload";private static final String final_dir = "C:\\Users\\Administrator\\Desktop\\test";/*** 上传文件** @param request* @return* @throws IllegalStateException* @throws IOException*/@RequestMapping(value = "/upload")public Map<String, Object> upload(HttpServletRequest request, @RequestParam(value = "data",required = false) MultipartFile multipartFile) throws IllegalStateException, IOException, Exception {String uuid = request.getParameter("uuid");String fileName = request.getParameter("name");//总大小String size = request.getParameter("size");//总片数int total = Integer.valueOf(request.getParameter("total"));//当前是第几片int index = Integer.valueOf(request.getParameter("index"));//整个文件的md5String fileMd5 = request.getParameter("filemd5"); //文件第一个分片上传的日期(如:20200118)String date = request.getParameter("date"); //分片的md5String md5 = request.getParameter("md5"); //生成上传文件的路径信息，按天生成String savePath = "\\upload" + File.separator + date;String saveDirectory = temp_dir + savePath +File.separator+uuid;//验证路径是否存在，不存在则创建目录File path = new File(saveDirectory);if (!path.exists()) {path.mkdirs();}//文件分片位置//File file = new File(saveDirectory, uuid + "_" + index);multipartFile.transferTo(new File(saveDirectory, uuid + "_" + index));if (path.isDirectory()) {File[] fileArray = path.listFiles();if (fileArray != null) {if (fileArray.length == total) {//分块全部上传完毕,合并String suffix = NameUtil.getExtensionName(fileName);String dir = final_dir + savePath;File newFile = new File(dir, uuid + "." + suffix);File copyDir = new File(dir);if(!copyDir.mkdir()){copyDir.mkdirs();}FileOutputStream outputStream = new FileOutputStream(newFile, true);//文件追加写入byte[] byt = new byte[10 * 1024 * 1024];int len;// FileInputStream temp = null;//分片文件for (int i = 0; i < total; i++) {int j = i + 1;FileInputStream temp  = new FileInputStream(new File(saveDirectory, uuid + "_" + j));while ((len = temp.read(byt)) != -1) {System.out.println("-----" + len);outputStream.write(byt, 0, len);}//关闭流temp.close();}outputStream.close();//删除临时文件FileUtil.deleteFolder( temp_dir+ savePath +File.separator+uuid);}}}HashMap map = new HashMap<>();map.put("fileId", uuid);return map;}/*** 上传文件前获取id和日期（如果是分片上传这一步可以交给前端处理）** @param request* @return* @throws IOException*/@RequestMapping(value = "/isUpload")public Map<String, Object> getUpload(HttpServletRequest request) throws Exception {HashMap<String,Object> map = new HashMap<>();String uuid = UUID.randomUUID().toString();map.put("fileId", uuid);map.put("date", formatter.format(LocalDateTime.now()));return map;}}

分片前端展示：

<!DOCTYPE HTML>
<html>
<head><meta charset="utf-8"><title>HTML5大文件分片上传示例</title><script src="http://cdn.bootcss.com/jquery/1.12.4/jquery.min.js"></script><script type="text/javascript" src="/static/md5.js"></script><script>var i = -1;var succeed = 0;var databgein;  //开始时间var dataend;    //结束时间var action = false;    //false检验分片是否上传过(默认); true上传文件var page = {init: function () {$("#upload").click(function () {$("#upload").attr('disabled', true)databgein = new Date();var file = $("#file")[0].files[0];  //文件对象isUpload(file);});}};$(function () {page.init();});function isUpload(file) {//构造一个表单，FormData是HTML5新增的var form = new FormData();var r = new FileReader();r.readAsBinaryString(file);$(r).load(function (e) {var bolb = e.target.result;var md5 = hex_md5(bolb);form.append("md5", md5);//Ajax提交$.ajax({url: "http://localhost:8080//burst/test/isUpload",type: "POST",data: form,//异步async: true,       //很重要，告诉jquery不要对form进行处理processData: false,  //很重要，指定为false才能形成正确的Content-TypecontentType: false,  success: function (dataObj) {// var dataObj = eval("("+data+")");var uuid = dataObj.fileId;var date = dataObj.date;//没有上传过文件upload(file, uuid, md5, date);}, error: function (XMLHttpRequest, textStatus, errorThrown) {alert("服务器出错!");}});})}/** file 文件对象* uuid 后端生成的uuid* filemd5 整个文件的md5* date  文件第一个分片上传的日期(如:20170122)*/function upload(file, uuid, filemd5, date) {name = file.name;        //文件名size = file.size;        //总大小var shardSize = 512 * 1024,    //以0.5m为一个分片shardCount = Math.ceil(size / shardSize);  //总片数if (i > shardCount) {i = -1;i = shardCount;} else {i += 1;  //只有在检测分片时,i才去加1; 上传文件时无需加1}//计算每一片的起始与结束位置var start = i * shardSize,end = Math.min(size, start + shardSize);//构造一个表单，FormData是HTML5新增的var form = new FormData();form.append("action", "upload");  //直接上传分片form.append("data", file.slice(start, end));  //slice方法用于切出文件的一部分$("#param").append("action==upload ");form.append("uuid", uuid);form.append("filemd5", filemd5);form.append("date", date);form.append("name", name);form.append("size", size);form.append("total", shardCount);  //总片数form.append("index", i + 1);        //当前是第几片var ssindex = i + 1;$("#param").append("index==" + ssindex + "<br/>");//按大小切割文件段　　var data = file.slice(start, end);var r = new FileReader();r.readAsBinaryString(data);$(r).load(function (e) {var bolb = e.target.result;var md5 = hex_md5(bolb);form.append("md5", md5);//Ajax提交$.ajax({url: "http://localhost:8080//burst/test/upload",type: "POST",data: form,async: true,        //异步processData: false,  //很重要，告诉jquery不要对form进行处理contentType: false,  //很重要，指定为false才能形成正确的Content-Typesuccess: function (dataObj) {//var dataObj = eval("("+data+")");var fileuuid = dataObj.fileId;//服务器返回分片是否上传成功//改变界面++succeed;$("#output").text(succeed + " / " + shardCount);if (i + 1 == shardCount) {dataend = new Date();$("#uuid").append(fileuuid);$("#usetime").append(dataend.getTime() - databgein.getTime());$("#upload").attr('disabled', false);} else if (i + 1 < shardCount) {//递归调用                　upload(file, uuid, filemd5, date);} else {i = -1;succeed = 0;$("#upload").attr('disabled', true)databgein = new Date();file = $("#file")[0].files[0];  //文件对象isUpload(file);}}, error: function (XMLHttpRequest, textStatus, errorThrown) {$("#upload").attr('disabled', false);alert("服务器出错!");}});})}</script></head><body><input type="file" id="file"/><button id="upload">上传</button><span id="output" style="font-size:12px">等待</span><span id="usetime" style="font-size:12px;margin-left:20px;">用时</span><span id="uuid" style="font-size:12px;margin-left:20px;">uuid==</span><br/><br/>
<br/>
<br/>
<span id="param" style="font-size:12px;margin-left:20px;">param==</span></body></html>

分片上传每当一次上传失败，都需要重新生成一个上传唯一uuid,全部从头开始上传。但是相对后面断点续传 同样有上传与服务器的交互少了一半，不用依赖数据库的优点。

二、断点续传

断点续传的原理：前端首先请求接口通过上传文件的MD5来获取此次是否上传，如果上传通过md5将上一次的uuid返回给前端。前端将所要上传文件进行分片，在上传的时候包含 服务器返回给前端的 该次上传的uuid，该篇文件的md5，上传的第几片的的标识，首先去检查是否此片是否上传，如果上传，直接跳到下一片的检查。如果没有上传，再上传文件。上传第一片的时候将信息记录到mysql。等上传完毕，将文件信息改为上传成功。删除临时文件夹。
1、由于首先添加配置文件 application.properties和 入口controller已经添加，这里不再继续贴出。

2、上传具体controller

@RestController
@RequestMapping(value = "/breakpointBusrt/test")
public class BreakpointBurstController {@Autowiredprivate FileUploadService fileUploadService;private static final DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMdd");private static final String temp_dir = "C:\\Users\\Administrator\\Desktop\\upload";private static final String final_dir = "C:\\Users\\Administrator\\Desktop\\test";/*** 上传文件** @param request* @return* @throws IllegalStateException* @throws IOException*/@RequestMapping(value = "/upload")public Map<String, Object> upload(HttpServletRequest request, @RequestParam(value = "data",required = false) MultipartFile multipartFile) throws IllegalStateException, IOException, Exception {String action = request.getParameter("action");String uuid = request.getParameter("uuid");String fileName = request.getParameter("name");String size = request.getParameter("size");//总大小int total = Integer.valueOf(request.getParameter("total"));//总片数int index = Integer.valueOf(request.getParameter("index"));//当前是第几片String fileMd5 = request.getParameter("filemd5"); //整个文件的md5String date = request.getParameter("date"); //文件第一个分片上传的日期(如:20170122)String md5 = request.getParameter("md5"); //分片的md5//生成上传文件的路径信息，按天生成String savePath = "\\upload" + File.separator + date;String saveDirectory = temp_dir + savePath +File.separator+uuid;//验证路径是否存在，不存在则创建目录File path = new File(saveDirectory);if (!path.exists()) {path.mkdirs();}//文件分片位置File file = new File(saveDirectory, uuid + "_" + index);//根据action不同执行不同操作. check:校验分片是否上传过; upload:直接上传分片Map<String, Object> map = null;if("check".equals(action)){String md5Str = FileMd5Util.getFileMD5(file);if (md5Str != null && md5Str.length() == 31) {System.out.println("check length =" + md5.length() + " md5Str length" + md5Str.length() + "   " + md5 + " " + md5Str);md5Str = "0" + md5Str;}if (md5Str != null && md5Str.equals(md5)) {//分片已上传过map = new HashMap<>();map.put("flag", "2");map.put("fileId", uuid);map.put("status", true);return map;} else {//分片未上传map = new HashMap<>();map.put("flag", "1");map.put("fileId", uuid);map.put("status", true);return map;}}else if("upload".equals(action)){//分片上传过程中出错,有残余时需删除分块后,重新上传if (file.exists()) {file.delete();}multipartFile.transferTo(new File(saveDirectory, uuid + "_" + index));}if (path.isDirectory()) {File[] fileArray = path.listFiles();if (fileArray != null) {if (fileArray.length == total) {//分块全部上传完毕,合并String suffix = NameUtil.getExtensionName(fileName);String dir = final_dir + savePath;File newFile = new File(dir, uuid + "." + suffix);File copyDir = new File(dir);if(!copyDir.mkdir()){copyDir.mkdirs();}//文件追加写入FileOutputStream outputStream = new FileOutputStream(newFile, true);byte[] byt = new byte[10 * 1024 * 1024];int len;//FileInputStream temp = null;//分片文件for (int i = 0; i < total; i++) {int j = i + 1;FileInputStream temp = new FileInputStream(new File(saveDirectory, uuid + "_" + j));while ((len = temp.read(byt)) != -1) {System.out.println("-----" + len);outputStream.write(byt, 0, len);}//关闭流temp.close();}outputStream.close();//修改FileRes记录为上传成功fileUploadService.updateUploadRecord(fileMd5, FileConstant.FileStatusEnum.UPLOAD_FINSH.getStatus());}else if(index == 1){//文件第一个分片上传时记录到数据库FileUploadRecord fileUploadRecord = new FileUploadRecord();String name = NameUtil.getFileNameNoEx(fileName);if (name.length() > 50) {name = name.substring(0, 50);}String suffix = NameUtil.getExtensionName(fileName);fileUploadRecord.setName(name);fileUploadRecord.setTimeContent(date);fileUploadRecord.setUuid(uuid);fileUploadRecord.setPath(savePath + File.separator + uuid + "." + suffix);fileUploadRecord.setSize(size);fileUploadRecord.setMd5(fileMd5);fileUploadRecord.setStatus(FileConstant.FileStatusEnum.UPLOAD_BEGIN.getStatus());fileUploadService.insertUploadRecord(fileUploadRecord);}}}map = new HashMap<>();map.put("flag", "3");map.put("fileId", uuid);map.put("status", true);return map;}/*** 上传文件前校验** @param request* @return* @throws IOException*/@RequestMapping(value = "/isUpload")public Map<String, Object> isUpload(HttpServletRequest request) throws Exception {String fileMd5 = request.getParameter("md5");FileUploadRecord fileUploadRecord=fileUploadService.findByFileMd5(fileMd5);HashMap<String,Object> map = new HashMap<>();if(Objects.isNull(fileUploadRecord)){//没有上传过文件String uuid = UUID.randomUUID().toString();map.put("flag", "1");map.put("fileId", uuid);map.put("date", formatter.format(LocalDateTime.now()));map.put("status", true);return map;}if(FileConstant.FileStatusEnum.UPLOAD_FINSH.getStatus().equals(fileUploadRecord.getStatus())){//文件上传成功map.put("flag", "3");map.put("fileId", fileUploadRecord.getUuid());map.put("date",fileUploadRecord.getTimeContent());map.put("status", true);return map;}if(FileConstant.FileStatusEnum.UPLOAD_FINSH.getStatus().equals(fileUploadRecord.getStatus())){map.put("flag", "1");map.put("fileId",  fileUploadRecord.getUuid());map.put("date", fileUploadRecord.getTimeContent());map.put("status", true);return map;}//状态不对String uuid = UUID.randomUUID().toString();map.put("flag", "1");map.put("fileId", uuid);map.put("date", formatter.format(LocalDateTime.now()));map.put("status", true);return map;}}

3、上传的前端页面

<!DOCTYPE HTML>
<html>
<head><meta charset="utf-8"><title>HTML5大文件分片上传示例</title><script src="http://cdn.bootcss.com/jquery/1.12.4/jquery.min.js"></script><script type="text/javascript"  src="/static/md5.js"></script><script>var i = -1;var succeed = 0;var databgein;  //开始时间var dataend;    //结束时间var action=false;    //false检验分片是否上传过(默认); true上传文件var page = {init: function(){$("#upload").click(function(){$("#upload").attr('disabled',true)databgein=new Date();var file = $("#file")[0].files[0];  //文件对象isUpload(file);});}};$(function(){page.init();});function isUpload (file) {//构造一个表单，FormData是HTML5新增的var form = new FormData();var r = new FileReader();r.readAsBinaryString(file);$(r).load(function(e){var bolb = e.target.result;var md5 = hex_md5(bolb);form.append("md5", md5);//Ajax提交$.ajax({url: "http://localhost:8080//breakpointBusrt/test/isUpload",type: "POST",data: form,async: true,        //异步processData: false,  //很重要，告诉jquery不要对form进行处理contentType: false,  //很重要，指定为false才能形成正确的Content-Typesuccess: function(dataObj){// var dataObj = eval("("+data+")");var uuid = dataObj.fileId;var date = dataObj.date;if (dataObj.flag == "1") {//没有上传过文件upload(file,uuid,md5,date);} else if(dataObj.flag == "2") {//已经上传部分upload(file,uuid,md5,date);} else if(dataObj.flag == "3") {//文件已经上传过alert("文件已经上传过,秒传了！！");$("#uuid").append(uuid);}},error: function(XMLHttpRequest, textStatus, errorThrown) {alert("服务器出错!");}});})}/** file 文件对象* uuid 后端生成的uuid* filemd5 整个文件的md5* date  文件第一个分片上传的日期*/function upload (file,uuid,filemd5,date) {name = file.name;        //文件名size = file.size;        //总大小var shardSize = 512 * 1024 ,    //以0.5m为一个分片shardCount = Math.ceil(size / shardSize);  //总片数if (i > shardCount) {i = -1;i = shardCount;} else {if(!action){i += 1;  //只有在检测分片时,i才去加1; 上传文件时无需加1}}//计算每一片的起始与结束位置var start = i * shardSize,end = Math.min(size, start + shardSize);//构造一个表单，FormData是HTML5新增的var form = new FormData();if(!action){form.append("action", "check");  //检测分片是否上传$("#param").append("action==check ");}else{form.append("action", "upload");  //直接上传分片form.append("data", file.slice(start,end));  //slice方法用于切出文件的一部分$("#param").append("action==upload ");}form.append("uuid", uuid);form.append("filemd5", filemd5);form.append("date", date);form.append("name", name);form.append("size", size);form.append("total", shardCount);  //总片数form.append("index", i+1);        //当前是第几片var ssindex = i+1;$("#param").append("index=="+ssindex+"<br/>");//按大小切割文件段　　var data = file.slice(start, end);var r = new FileReader();r.readAsBinaryString(data);$(r).load(function(e){var bolb = e.target.result;var md5 = hex_md5(bolb);form.append("md5", md5);//Ajax提交$.ajax({url: "http://localhost:8080//breakpointBusrt/test/upload",type: "POST",data: form,async: true,        //异步processData: false,  //很重要，告诉jquery不要对form进行处理contentType: false,  //很重要，指定为false才能形成正确的Content-Typesuccess: function(dataObj){var fileuuid = dataObj.fileId;var flag = dataObj.flag;//服务器返回该分片是否上传过if(!action){if (flag == "1") {//未上传action = true;} else if(dataObj.flag == "2") {//已上传action = false;++succeed;}//递归调用                　upload(file,uuid,filemd5,date);}else{//服务器返回分片是否上传成功//改变界面++succeed;$("#output").text(succeed + " / " + shardCount);if (i+1 == shardCount) {dataend=new Date();$("#uuid").append(fileuuid);$("#usetime").append(dataend.getTime()-databgein.getTime());$("#upload").attr('disabled',false);} else {//已上传成功,然后检测下一个分片action = false;//递归调用                　upload(file,uuid,filemd5,date);}}},error: function(XMLHttpRequest, textStatus, errorThrown) {$("#upload").attr('disabled',false);alert("服务器出错!");}});})}</script></head><body><input type="file" id="file" /><button id="upload">上传</button><span id="output" style="font-size:12px">等待</span><span id="usetime" style="font-size:12px;margin-left:20px;">用时</span><span id="uuid" style="font-size:12px;margin-left:20px;">uuid==</span><br/><br/>
<br/>
<br/>
<span id="param" style="font-size:12px;margin-left:20px;">param==</span></body></html>

这里用到mybatis，mybatis大家都有用到。这里就仅将使用到建表语句和实体类贴出

DROP TABLE IF EXISTS `upload_file_record`;
CREATE TABLE `upload_file_record`  (`uuid` varchar(50) not null,`name` varchar(50)   not null COMMENT '文件名',`timeContent` varchar(10) not NULL COMMENT 'yyyyMMdd',`c_path` varchar(225) CHARACTER SET utf8 COLLATE utf8_general_ci not NULL COMMENT '文件地址',`c_size` varchar(20) CHARACTER SET utf8 COLLATE utf8_general_ci not NULL  COMMENT '大小',`file_md5` varchar(100) CHARACTER SET utf8 COLLATE utf8_general_ci not NULL  COMMENT 'fileMd5',`status`  TINYINT(2)  not NULL  COMMENT '文件上传状态',`createTime` TIMESTAMP   COMMENT '创建时间',PRIMARY KEY (`uuid`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8 COLLATE = utf8_general_ci ROW_FORMAT = Compact;

实体类：

package com.yin.freemakeradd.pojo;import com.yin.freemakeradd.utils.NameUtil;import java.io.File;/*** @author yin* @Date 2020/1/17 22:31* @Method*/@Data
public class FileUploadRecord {private String uuid;private String name;private String timeContent;private String path;private String size;private String md5;private Integer status;private String createTime;

附（这里将使用到工具类和md5.js贴出）：

1、服务端使用md5生成工具

public class FileMd5Util {public static final String KEY_MD5 = "MD5";public static final String CHARSET_ISO88591 = "ISO-8859-1";/*** Get MD5 of one file:hex string,test OK!** @param file* @return*/public static String getFileMD5(File file) {if (!file.exists() || !file.isFile()) {return null;}MessageDigest digest = null;FileInputStream in = null;byte buffer[] = new byte[1024];int len;try {digest = MessageDigest.getInstance("MD5");in = new FileInputStream(file);while ((len = in.read(buffer, 0, 1024)) != -1) {digest.update(buffer, 0, len);}in.close();} catch (Exception e) {e.printStackTrace();return null;}BigInteger bigInt = new BigInteger(1, digest.digest());return bigInt.toString(16);}/**** Get MD5 of one file！test ok!** @param filepath* @return*/public static String getFileMD5(String filepath) {File file = new File(filepath);return getFileMD5(file);}/*** MD5 encrypt,test ok** @param data* @return byte[]* @throws Exception*/public static byte[] encryptMD5(byte[] data) throws Exception {MessageDigest md5 = MessageDigest.getInstance(KEY_MD5);md5.update(data);return md5.digest();}public static byte[] encryptMD5(String data) throws Exception {return encryptMD5(data.getBytes(CHARSET_ISO88591));}/**** compare two file by Md5** @param file1* @param file2* @return*/public static boolean isSameMd5(File file1,File file2){String md5_1= FileMd5Util.getFileMD5(file1);String md5_2= FileMd5Util.getFileMD5(file2);return md5_1.equals(md5_2);}/**** compare two file by Md5** @param filepath1* @param filepath2* @return*/public static boolean isSameMd5(String filepath1,String filepath2){File file1=new File(filepath1);File file2=new File(filepath2);return isSameMd5(file1, file2);}}

2、文件名生成工具。

public class NameUtil {/*** Java文件操作 获取文件扩展名*/public static String getExtensionName(String filename) {if ((filename != null) && (filename.length() > 0)) {int dot = filename.lastIndexOf('.');if ((dot > -1) && (dot < (filename.length() - 1))) {return filename.substring(dot + 1);}}return filename.toLowerCase();}/*** Java文件操作 获取不带扩展名的文件名*/public static String getFileNameNoEx(String filename) {if ((filename != null) && (filename.length() > 0)) {int dot = filename.lastIndexOf('.');if ((dot > -1) && (dot < (filename.length()))) {return filename.substring(0, dot);}}return filename.toLowerCase();}public static void main(String[] args) {String str = "AAbbbCC.jpg";System.out.println(getExtensionName(str).toLowerCase());System.out.println(getFileNameNoEx(str).toUpperCase());}
}

删除文件工具类

package com.yin.freemakeradd.utils;import java.io.File;public class FileUtil {/*** 删除单个文件* @param   filePath    被删除文件的文件名* @return 文件删除成功返回true，否则返回false*/public static boolean deleteFile(String filePath) {File file = new File(filePath);if (file.isFile() && file.exists()) {return file.delete();}return false;}/*** 删除文件夹以及目录下的文件* @param   filePath 被删除目录的文件路径* @return  目录删除成功返回true，否则返回false*/public static boolean deleteDirectory(String filePath) {boolean flag = false;//如果filePath不以文件分隔符结尾，自动添加文件分隔符if (!filePath.endsWith(File.separator)) {filePath = filePath + File.separator;}File dirFile = new File(filePath);if (!dirFile.exists() || !dirFile.isDirectory()) {return false;}flag = true;File[] files = dirFile.listFiles();//遍历删除文件夹下的所有文件(包括子目录)for (int i = 0; i < files.length; i++) {if (files[i].isFile()) {//删除子文件flag = deleteFile(files[i].getAbsolutePath());if (!flag){break;}} else {//删除子目录flag = deleteDirectory(files[i].getAbsolutePath());if (!flag){break;}}}if (!flag){return false;}//删除当前空目录return dirFile.delete();}/*** 根据路径删除指定的目录或文件，无论存在与否* @param filePath  要删除的目录或文件* @return 删除成功返回 true，否则返回 false。*/public static boolean deleteFolder(String filePath) {File file = new File(filePath);if (!file.exists()) {return false;} else {if (file.isFile()) {// 为文件时调用删除文件方法return deleteFile(filePath);} else {// 为目录时调用删除目录方法return deleteDirectory(filePath);}}}public static void main(String[] args) {deleteFolder("C:\\Users\\Administrator\\Desktop\\upload"+"\\upload" + File.separator + "20200118"+File.separator+"eed4e9e3-52f0-4755-a391-aaba54d606cc");}
}

前端引入md5.js文件

/* A JavaScript implementation of the RSA Data Security, Inc. MD5 Message
* Digest Algorithm, as defined in RFC 1321.
* Version 2.1 Copyright (C) Paul Johnston 1999 - 2002.
* Other contributors: Greg Holt, Andrew Kepert, Ydnar, Lostinet
* Distributed under the BSD License
* See http://pajhome.org.uk/crypt/md5 for more info.*//** Configurable variables. You may need to tweak these to be compatible with* the server-side, but the defaults work in most cases.*/
var hexcase = 0;  /* hex output format. 0 - lowercase; 1 - uppercase        */
var b64pad  = ""; /* base-64 pad character. "=" for strict RFC compliance   */
var chrsz   = 8;  /* bits per input character. 8 - ASCII; 16 - Unicode      *//** These are the functions you'll usually want to call* They take string arguments and return either hex or base-64 encoded strings*/
function hex_md5(s){ return binl2hex(core_md5(str2binl(s), s.length * chrsz));}
function b64_md5(s){ return binl2b64(core_md5(str2binl(s), s.length * chrsz));}
function str_md5(s){ return binl2str(core_md5(str2binl(s), s.length * chrsz));}
function hex_hmac_md5(key, data) { return binl2hex(core_hmac_md5(key, data)); }
function b64_hmac_md5(key, data) { return binl2b64(core_hmac_md5(key, data)); }
function str_hmac_md5(key, data) { return binl2str(core_hmac_md5(key, data)); }/** Perform a simple self-test to see if the VM is working*/
function md5_vm_test()
{return hex_md5("abc") == "900150983cd24fb0d6963f7d28e17f72";
}/** Calculate the MD5 of an array of little-endian words, and a bit length*/
function core_md5(x, len)
{/* append padding */x[len >> 5] |= 0x80 << ((len) % 32);x[(((len + 64) >>> 9) << 4) + 14] = len;var a =  1732584193;var b = -271733879;var c = -1732584194;var d =  271733878;for(var i = 0; i < x.length; i += 16){var olda = a;var oldb = b;var oldc = c;var oldd = d;a = md5_ff(a, b, c, d, x[i+ 0], 7 , -680876936);d = md5_ff(d, a, b, c, x[i+ 1], 12, -389564586);c = md5_ff(c, d, a, b, x[i+ 2], 17,  606105819);b = md5_ff(b, c, d, a, x[i+ 3], 22, -1044525330);a = md5_ff(a, b, c, d, x[i+ 4], 7 , -176418897);d = md5_ff(d, a, b, c, x[i+ 5], 12,  1200080426);c = md5_ff(c, d, a, b, x[i+ 6], 17, -1473231341);b = md5_ff(b, c, d, a, x[i+ 7], 22, -45705983);a = md5_ff(a, b, c, d, x[i+ 8], 7 ,  1770035416);d = md5_ff(d, a, b, c, x[i+ 9], 12, -1958414417);c = md5_ff(c, d, a, b, x[i+10], 17, -42063);b = md5_ff(b, c, d, a, x[i+11], 22, -1990404162);a = md5_ff(a, b, c, d, x[i+12], 7 ,  1804603682);d = md5_ff(d, a, b, c, x[i+13], 12, -40341101);c = md5_ff(c, d, a, b, x[i+14], 17, -1502002290);b = md5_ff(b, c, d, a, x[i+15], 22,  1236535329);a = md5_gg(a, b, c, d, x[i+ 1], 5 , -165796510);d = md5_gg(d, a, b, c, x[i+ 6], 9 , -1069501632);c = md5_gg(c, d, a, b, x[i+11], 14,  643717713);b = md5_gg(b, c, d, a, x[i+ 0], 20, -373897302);a = md5_gg(a, b, c, d, x[i+ 5], 5 , -701558691);d = md5_gg(d, a, b, c, x[i+10], 9 ,  38016083);c = md5_gg(c, d, a, b, x[i+15], 14, -660478335);b = md5_gg(b, c, d, a, x[i+ 4], 20, -405537848);a = md5_gg(a, b, c, d, x[i+ 9], 5 ,  568446438);d = md5_gg(d, a, b, c, x[i+14], 9 , -1019803690);c = md5_gg(c, d, a, b, x[i+ 3], 14, -187363961);b = md5_gg(b, c, d, a, x[i+ 8], 20,  1163531501);a = md5_gg(a, b, c, d, x[i+13], 5 , -1444681467);d = md5_gg(d, a, b, c, x[i+ 2], 9 , -51403784);c = md5_gg(c, d, a, b, x[i+ 7], 14,  1735328473);b = md5_gg(b, c, d, a, x[i+12], 20, -1926607734);a = md5_hh(a, b, c, d, x[i+ 5], 4 , -378558);d = md5_hh(d, a, b, c, x[i+ 8], 11, -2022574463);c = md5_hh(c, d, a, b, x[i+11], 16,  1839030562);b = md5_hh(b, c, d, a, x[i+14], 23, -35309556);a = md5_hh(a, b, c, d, x[i+ 1], 4 , -1530992060);d = md5_hh(d, a, b, c, x[i+ 4], 11,  1272893353);c = md5_hh(c, d, a, b, x[i+ 7], 16, -155497632);b = md5_hh(b, c, d, a, x[i+10], 23, -1094730640);a = md5_hh(a, b, c, d, x[i+13], 4 ,  681279174);d = md5_hh(d, a, b, c, x[i+ 0], 11, -358537222);c = md5_hh(c, d, a, b, x[i+ 3], 16, -722521979);b = md5_hh(b, c, d, a, x[i+ 6], 23,  76029189);a = md5_hh(a, b, c, d, x[i+ 9], 4 , -640364487);d = md5_hh(d, a, b, c, x[i+12], 11, -421815835);c = md5_hh(c, d, a, b, x[i+15], 16,  530742520);b = md5_hh(b, c, d, a, x[i+ 2], 23, -995338651);a = md5_ii(a, b, c, d, x[i+ 0], 6 , -198630844);d = md5_ii(d, a, b, c, x[i+ 7], 10,  1126891415);c = md5_ii(c, d, a, b, x[i+14], 15, -1416354905);b = md5_ii(b, c, d, a, x[i+ 5], 21, -57434055);a = md5_ii(a, b, c, d, x[i+12], 6 ,  1700485571);d = md5_ii(d, a, b, c, x[i+ 3], 10, -1894986606);c = md5_ii(c, d, a, b, x[i+10], 15, -1051523);b = md5_ii(b, c, d, a, x[i+ 1], 21, -2054922799);a = md5_ii(a, b, c, d, x[i+ 8], 6 ,  1873313359);d = md5_ii(d, a, b, c, x[i+15], 10, -30611744);c = md5_ii(c, d, a, b, x[i+ 6], 15, -1560198380);b = md5_ii(b, c, d, a, x[i+13], 21,  1309151649);a = md5_ii(a, b, c, d, x[i+ 4], 6 , -145523070);d = md5_ii(d, a, b, c, x[i+11], 10, -1120210379);c = md5_ii(c, d, a, b, x[i+ 2], 15,  718787259);b = md5_ii(b, c, d, a, x[i+ 9], 21, -343485551);a = safe_add(a, olda);b = safe_add(b, oldb);c = safe_add(c, oldc);d = safe_add(d, oldd);}return Array(a, b, c, d);}/** These functions implement the four basic operations the algorithm uses.*/
function md5_cmn(q, a, b, x, s, t)
{return safe_add(bit_rol(safe_add(safe_add(a, q), safe_add(x, t)), s),b);
}
function md5_ff(a, b, c, d, x, s, t)
{return md5_cmn((b & c) | ((~b) & d), a, b, x, s, t);
}
function md5_gg(a, b, c, d, x, s, t)
{return md5_cmn((b & d) | (c & (~d)), a, b, x, s, t);
}
function md5_hh(a, b, c, d, x, s, t)
{return md5_cmn(b ^ c ^ d, a, b, x, s, t);
}
function md5_ii(a, b, c, d, x, s, t)
{return md5_cmn(c ^ (b | (~d)), a, b, x, s, t);
}/** Calculate the HMAC-MD5, of a key and some data*/
function core_hmac_md5(key, data)
{var bkey = str2binl(key);if(bkey.length > 16) bkey = core_md5(bkey, key.length * chrsz);var ipad = Array(16), opad = Array(16);for(var i = 0; i < 16; i++){ipad[i] = bkey[i] ^ 0x36363636;opad[i] = bkey[i] ^ 0x5C5C5C5C;}var hash = core_md5(ipad.concat(str2binl(data)), 512 + data.length * chrsz);return core_md5(opad.concat(hash), 512 + 128);
}/** Add integers, wrapping at 2^32. This uses 16-bit operations internally* to work around bugs in some JS interpreters.*/
function safe_add(x, y)
{var lsw = (x & 0xFFFF) + (y & 0xFFFF);var msw = (x >> 16) + (y >> 16) + (lsw >> 16);return (msw << 16) | (lsw & 0xFFFF);
}/** Bitwise rotate a 32-bit number to the left.*/
function bit_rol(num, cnt)
{return (num << cnt) | (num >>> (32 - cnt));
}/** Convert a string to an array of little-endian words* If chrsz is ASCII, characters >255 have their hi-byte silently ignored.*/
function str2binl(str)
{var bin = Array();var mask = (1 << chrsz) - 1;for(var i = 0; i < str.length * chrsz; i += chrsz)bin[i>>5] |= (str.charCodeAt(i / chrsz) & mask) << (i%32);return bin;
}/** Convert an array of little-endian words to a string*/
function binl2str(bin)
{var str = "";var mask = (1 << chrsz) - 1;for(var i = 0; i < bin.length * 32; i += chrsz)str += String.fromCharCode((bin[i>>5] >>> (i % 32)) & mask);return str;
}/** Convert an array of little-endian words to a hex string.*/
function binl2hex(binarray)
{var hex_tab = hexcase ? "0123456789ABCDEF" : "0123456789abcdef";var str = "";for(var i = 0; i < binarray.length * 4; i++){str += hex_tab.charAt((binarray[i>>2] >> ((i%4)*8+4)) & 0xF) +hex_tab.charAt((binarray[i>>2] >> ((i%4)*8  )) & 0xF);}return str;
}/** Convert an array of little-endian words to a base-64 string*/
function binl2b64(binarray)
{var tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";var str = "";for(var i = 0; i < binarray.length * 4; i += 3){var triplet = (((binarray[i   >> 2] >> 8 * ( i   %4)) & 0xFF) << 16)| (((binarray[i+1 >> 2] >> 8 * ((i+1)%4)) & 0xFF) << 8 )|  ((binarray[i+2 >> 2] >> 8 * ((i+2)%4)) & 0xFF);for(var j = 0; j < 4; j++){if(i * 8 + j * 6 > binarray.length * 32) str += b64pad;else str += tab.charAt((triplet >> 6*(3-j)) & 0x3F);}}return str;
}