java实现文件的断点续传：
依赖：
<!--文件上传-->
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.2.1</version>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>1.4</version>
</dependency>
前端实现：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>文件上传</title> <script type="text/javascript" src="js/jquery-1.8.3.min.js" ></script> </head> <body> <div class="row"> <label for="fileToUpload">请选择需要上传的文件</label> <input type="file" name="fileToUpload" id="fileToUpload" onchange="fileSelected();" multiple/> </div> <div class="row"> <button onclick="uploadFiles()">上传</button> <button onclick="pauseUpload()">暂停</button> <label id="progressNumber"></label> </div> <div id="fileFrame"></div> <div id="msg" style="max-height: 400px; overflow:auto;min-height: 100px;"> </div> <br> <div><h6>支持批量，支持断点续传</h6></div> </body> <script> var msg = null; var paragraph = 1024*1024*2; //每次分片传输文件的大小 2M var blob = null;// 分片数据的载体Blob对象 var fileList = null; //传输的文件 var uploadState = 0; // 0: 无上传/取消， 1： 上传中， 2： 暂停 //初始化消息框 function init(){ msg = document.getElementById("msg"); } function uploadFiles(){ //将上传状态设置成1 uploadState = 1; if(fileList.files.length>0){ for(var i = 0; i< fileList.files.length; i++){ var file = fileList.files[i]; uploadFileInit(file,i); } }else{ msg.innerHTML = "请选择上传文件！"; } } /** * 获取服务器文件大小，开始续传 * @param file * @param i */ function uploadFileInit(file,i){ if(file){ var startSize = 0; var endSize = 0; var date = file.lastModifiedDate; var lastModifyTime = date.getFullYear()+"-"+(date.getMonth()+1)+"-"+date.getDate()+"-" +date.getHours()+"-"+date.getMinutes()+"-"+date.getSeconds() //获取当前文件已经上传大小 jQuery.post("http://localhost:8084/crm/file/getChunkedFileSize", {"fileName":encodeURIComponent(file.name),"fileSize":file.size,"lastModifyTime":lastModifyTime,"chunkedFileSize":"chunkedFileSize"}, function(data){ if(data != -1){ endSize = Number(data); } uploadFile(file,startSize,endSize,i); }); } } /** * 分片上传文件 */ function uploadFile(file,startSize,endSize,i) { var date = file.lastModifiedDate; var lastModifyTime = date.getFullYear()+"-"+(date.getMonth()+1)+"-"+date.getDate()+"-" +date.getHours()+"-"+date.getMinutes()+"-"+date.getSeconds() var reader = new FileReader(); reader.onload = function loaded(evt) { // 构造 XMLHttpRequest 对象，发送文件 Binary 数据 var xhr = new XMLHttpRequest(); xhr.sendAsBinary = function(text){ var data = new ArrayBuffer(text.length); var ui8a = new Uint8Array(data, 0); for (var i = 0; i < text.length; i++) ui8a[i] = (text.charCodeAt(i) & 0xff); this.send(ui8a); } xhr.onreadystatechange = function(){ if(xhr.readyState==4){ //表示服务器的相应代码是200；正确返回了数据 if(xhr.status==200){ //纯文本数据的接受方法 var message=xhr.responseText; message = Number(message); uploadProgress(file,startSize,message,i); } else{ msg.innerHTML = "上传出错，服务器相应错误！"; } } };//创建回调方法 xhr.open("POST", "http://localhost:8084/crm/file/appendUpload2Server/"+"?"+"fileName="+encodeURIComponent(file.name)+"&fileSize="+file.size+"&lastModifyTime="+lastModifyTime ,false); xhr.overrideMimeType("application/octet-stream;charset=utf-8"); xhr.sendAsBinary(evt.target.result); }; if(endSize < file.size){ //处理文件发送（字节） startSize = endSize; if(paragraph > (file.size - endSize)){ endSize = file.size; }else{ endSize += paragraph ; } if (file.webkitSlice) { //webkit浏览器 blob = file.webkitSlice(startSize, endSize); }else blob = file.slice(startSize, endSize); reader.readAsBinaryString(blob); }else{ document.getElementById('progressNumber'+i).innerHTML = '100%'; } } //显示处理进程 function uploadProgress(file,startSize,uploadLen,i) { var percentComplete = Math.round(uploadLen * 100 / file.size); document.getElementById('progressNumber'+i).innerHTML = percentComplete.toString() + '%'; //续传 if(uploadState == 1){ uploadFile(file,startSize,uploadLen,i); } } /* 暂停上传 */ function pauseUpload(){ uploadState = 2; } /** * 选择文件之后触发事件 */ function fileSelected() { fileList = document.getElementById('fileToUpload'); var length = fileList.files.length; var frame = document.getElementById('fileFrame'); for(var i=0; i<length; i++){ file = fileList.files[i]; if(file){ var fileSize = 0; if (file.size > 1024 * 1024) fileSize = (Math.round(file.size * 100 / (1024 * 1024)) / 100).toString() + 'MB'; else fileSize = (Math.round(file.size * 100 / 1024) / 100).toString() + 'KB'; var nameDiv = document.createElement("div"); nameDiv.setAttribute("id","fileName"+i); nameDiv.innerHTML='Name: ' + file.name; var sizeDiv = document.createElement("div"); sizeDiv.setAttribute("id","fileSize"+i); sizeDiv.innerHTML='fileSize: ' + fileSize; var typeDiv = document.createElement("div"); typeDiv.setAttribute("id","progressNumber"+i); typeDiv.innerHTML=''; } frame.appendChild(nameDiv); frame.appendChild(sizeDiv); frame.appendChild(typeDiv); } } </script> </html>
java后端工具类：
package com.zhl.push.utils; import org.omg.IOP.Encoding; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.File; import java.io.InputStream; import java.io.PrintWriter; import java.io.RandomAccessFile; /** * @Author * @ClassName ImgDdUploadUtil * @Description TODO * @Date 2018/11/9 15:46 * @Version 1.0 */ public class ImgDdUploadUtil { /** * 获取已上传的文件大小 * * @param request * @param */ public static Long getChunkedFileSize(HttpServletRequest request) { //存储文件的路径，根据自己实际确定 String currentFilePath = "E:\front\fileUpload\tinyImgUpload-master\20181109\"; // PrintWriter print = null; try { request.setCharacterEncoding("utf-8"); // print = response.getWriter(); String fileName = new String(request.getParameter("fileName").getBytes("ISO-8859-1"), "UTF-8"); String lastModifyTime = request.getParameter("lastModifyTime"); File file = new File(currentFilePath + fileName + "." + lastModifyTime); if (file.exists()) { return file.length(); } else { return -1L; } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } /** * 断点文件上传 1.先判断断点文件是否存在 2.存在直接流上传 3.不存在直接新创建一个文件 4.上传完成以后设置文件名称 */ public static Long appendUpload2Server(HttpServletRequest request) { try { request.setCharacterEncoding("utf-8"); String fileSize = request.getParameter("fileSize"); // long totalSize = StringUtil.toLong(fileSize); Long totalSize = 0L; if (fileSize != null && !fileSize.equals("")) { totalSize = Long.valueOf(fileSize); } RandomAccessFile randomAccessfile = null; long currentFileLength = 0;// 记录当前文件大小，用于判断文件是否上传完成 String currentFilePath = "E:\front\fileUpload\tinyImgUpload-master\20181109";// 记录当前文件的绝对路径 String fileName = new String(request.getParameter("fileName").getBytes("UTF-8"), "UTF-8"); String lastModifyTime = request.getParameter("lastModifyTime"); String filela = fileName.substring(fileName.lastIndexOf("."), fileName.length());//文件后缀 String filef = fileName.substring(0, fileName.lastIndexOf("."));//文件前缀 // File file = new File(currentFilePath+fileName+"."+lastModifyTime); File file = new File(currentFilePath+"/" + filef +"_"+ lastModifyTime + filela); // 存在文件 if (file.exists()) { randomAccessfile = new RandomAccessFile(file, "rw"); } else { // 不存在文件，根据文件标识创建文件 randomAccessfile = new RandomAccessFile(currentFilePath+"/" + filef +"_"+ lastModifyTime + filela, "rw"); } // 开始文件传输 InputStream in = request.getInputStream(); randomAccessfile.seek(randomAccessfile.length()); byte b[] = new byte[1024]; int n; while ((n = in.read(b)) != -1) { Thread.sleep(1000); randomAccessfile.write(b, 0, n); } currentFileLength = randomAccessfile.length(); // 关闭文件 closeRandomAccessFile(randomAccessfile); randomAccessfile = null; // 整个文件上传完成,修改文件后缀 // if (currentFileLength == totalSize) { // File oldFile = new File(currentFilePath + fileName + "." + lastModifyTime); // File newFile = new File(currentFilePath + fileName); // if (!oldFile.exists()) { // return -1L;//重命名文件不存在 // } // if (newFile.exists()) {// 如果存在形如test.txt的文件，则新的文件存储为test+当前时间戳.txt, 没处理不带扩展名的文件 // String newName = fileName.substring(0, fileName.lastIndexOf(".")) // + System.currentTimeMillis() + "." // + fileName.substring(fileName.lastIndexOf(".") + 1); // newFile = new File(currentFilePath + newName); // } // if (!oldFile.renameTo(newFile)) { // oldFile.delete(); // } // // } return currentFileLength; } catch (Exception e) { e.printStackTrace(); } return null; } /** * 关闭随机访问文件 * * @param */ public static void closeRandomAccessFile(RandomAccessFile rfile) { if (null != rfile) { try { rfile.close(); } catch (Exception e) { e.printStackTrace(); } } } }
Controller 层：
@RestController @RequestMapping("/file") public class FileUpload { @RequestMapping("/getChunkedFileSize") //requestParam要写才知道是前台的那个数组 public Long getChunkedFileSize(HttpServletRequest request){ Long chunkedFileSize = ImgDdUploadUtil.getChunkedFileSize(request); return chunkedFileSize; } @RequestMapping("/appendUpload2Server") //requestParam要写才知道是前台的那个数组 public Long appendUpload2Server(HttpServletRequest request){ Long aLong = ImgDdUploadUtil.appendUpload2Server(request); return aLong; } }