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;
}
}