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1.定义一个实体类
用于接收前台传过来的信息，信息应该包括总切片数，当前切片数，文件名称，文件总大小。
import com.geely.tcm.common.annotation.Excel;import lombok.Data; import javax.validation.constraints.Max;import javax.validation.constraints.Min;import javax.validation.constraints.NotNull;import java.io.Serializable; @Datapublic class MutilFileInfo implements Serializable { private static final long serialVersionUID = 1L; @NotNull(message = "车型不能为空") @Excel(name = "车型") private String model; @Excel(name = "文件名称") private String name; @Excel(name = "文件总大小") private Long totalSize; @Min(value = 1, message = "不能小于1") @Max(value = 10000, message = "不能大于10000") @Excel(name = "当前分片序号") private Integer chunk; @Min(value = 1, message = "不能小于1") @Max(value = 10000, message = "不能大于10000") @Excel(name = "分片总数") private Integer chunks;}2.创建controller
用于处理前端过来的文件及信息
import com.alibaba.fastjson.JSON;import com.baidubce.services.bos.model.PartETag;import com.geely.tcm.common.annotation.Log;import com.geely.tcm.common.bean.MutilFileInfo;import com.geely.tcm.common.bean.baidu.CustomPartETag;import com.geely.tcm.common.bean.measure.Cmm3dModel;import com.geely.tcm.common.configuration.RedisUtils;import com.geely.tcm.common.enums.BusinessType;import com.geely.tcm.common.util.StringUtils;import com.geely.tcom.remote.api.baidu.BaiduCloudBosService;import io.swagger.annotations.Api;import io.swagger.annotations.ApiImplicitParam;import io.swagger.annotations.ApiImplicitParams;import io.swagger.annotations.ApiOperation;import lombok.extern.slf4j.Slf4j;import org.apache.dubbo.config.annotation.DubboReference;import org.springframework.web.bind.annotation.PostMapping;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 java.util.*;import java.util.concurrent.Semaphore;import java.util.stream.Collectors; @Api(tags = "文件上传下载服务")@RequestMapping("/threeModel")@RestController@Slf4jpublic class Model3DController1 { //DubboReference这个是远程调用，如果没有远程调用，直接Autowired就可以 @DubboReference(version = "${sheet.service.version}") private BaiduCloudBosService baiduCloudBosService; //通过加锁保证线程安全 private Semaphore lock = new Semaphore(1); //api开头的这些是swagger用到的，如果没使用swagger可以删到PostMapping上边 @ApiOperation(value = "obj模型上传") @ApiImplicitParams({ @ApiImplicitParam(name = "totalSize", value = "文件总大小",dataTypeClass = Long.class), @ApiImplicitParam(name = "chunks", value = "总切片数",dataTypeClass = Integer.class), @ApiImplicitParam(name = "chunk", value = "当前切片数",dataTypeClass = Integer.class), @ApiImplicitParam(name = "model", value = "车型",dataTypeClass = String.class), @ApiImplicitParam(name = "file", value = "切片文件",dataTypeClass = MultipartFile.class) }) @Log(title = "obj模型上传", businessType = BusinessType.INSERT) @PostMapping("/upload3DToBos") public Object upload3DToBos( MutilFileInfo fileinfo, @RequestParam(required=false,value="file") MultipartFile multipartFile) { String model=fileinfo.getModel().trim(); Map<String,Object> m=new HashMap(); String fileName=fileinfo.getName(); if (StringUtils.isEmpty(fileName)) {//判断文件名称是否为空 m.put("key","error"); m.put("value","文件名不能为空"); return m; } if (multipartFile == null) {//判断上传过来的切片是否为空 m.put("key","error"); m.put("value","请上传文件"); return m; } try{ String filePath="/test/"+model+"/"+fileName;//拼接百度云地址 String redisKey="partETags-"+model+"-"+fileName;//缓存的键 Integer current =fileinfo.getChunk();//当前切片数 Integer total = fileinfo.getChunks();//总切片数 Long size=multipartFile.getSize();//文件大小 String uploadId = getUploadId(redisKey, filePath);//该方法获取百度云的唯一标识uploadId byte[] file = multipartFile.getBytes();//将切片过来的文件转成字节数组 if(current==1){//这块进行断点续传，如果是第一个切片，查询一下缓存中是否有数据了，如果有返回给前台，如果没有进行上传 if(getCurrentEqualsOne(redisKey).size()>0) { //给前台提供是否缓存中已有数据 return getCurrentEqualsOne(redisKey); } } //切片上传百度云 List<CustomPartETag> customPartETags = getPartEtags(redisKey, uploadId, filePath, file, size, current); //如果缓存中成功的切片数等于总数，那么进行合并 if (customPartETags.size() == total) { customPartETags = customPartETags.stream().sorted(Comparator.comparing(PartETag::getPartNumber)).collect(Collectors.toList());//进行排序 baiduCloudBosService.completePart(uploadId, customPartETags, filePath);//执行合并 RedisUtils.hdel(redisKey,"uploadId","customPartETags");//如果合并成功，删除缓存中的数据 // 入库做记录 m.put("key","success"); m.put("value","上传成功"); return m; } m.put("key","continue"); m.put("value",current+1); return m; }catch (Exception e){ e.printStackTrace(); m.put("key","error"); m.put("value","上传失败"); return m; } } private List<CustomPartETag> getPartEtags(String redisPartKey, String uploadId, String filePath, byte[] file, long size, int current) { List<CustomPartETag> customPartETags = null; try { lock.acquire(); //因为每次上传成功后都会把成功的切片存进百度云，如注解下方第四行代码，所以每次上传之前需要先取出来，将成功的切片放进去 customPartETags = RedisUtils.hget(redisPartKey, "customPartETags") == null ? new ArrayList<>() : JSON.parseArray((String) RedisUtils.hget(redisPartKey, "customPartETags"), CustomPartETag.class); //上传百度云成功之后会返回一个PartETagg对象，由于项目中存在dubbo，顾将CustomPartETag类继承PartETagg进行序列化 CustomPartETag customPartETag = baiduCloudBosService.uploadCustomPartETag(uploadId, filePath, file, size, current); customPartETags.add(customPartETag); setPartEtagsToRedis(redisPartKey, customPartETags); } catch (InterruptedException e) { e.printStackTrace(); } finally { lock.release(); } return customPartETags; } private String getUploadId(String redisPartKey, String filePath) { String uploadId = null; try { lock.acquire();//线程锁 uploadId = (String) RedisUtils.hget(redisPartKey, "uploadId");//先去redis中找，是否已经有uploadId if (StringUtils.isEmpty(uploadId)) {//判断是否为空，如果为空，说明之前没上传过，为首次上传，如果已经存在，返回该uploadId uploadId = baiduCloudBosService.initMultipartUpload(filePath);//进行初始化，返回一个唯一标识uploadId RedisUtils.hset(redisPartKey, "uploadId", uploadId, 60 * 60);//将返回来的uploadId放到缓存中，下个切片上传直接使用这个uploadId } } catch (InterruptedException e) { e.printStackTrace(); } finally { lock.release(); } return uploadId; } private void setPartEtagsToRedis(String redisPartKey, List<CustomPartETag> customPartETags) { RedisUtils.hset(redisPartKey, "customPartETags", JSON.toJSONString(customPartETags), 60 * 60); } public Map<String,Object> getCurrentEqualsOne(String redisKey){ Map<String,Object> m=new HashMap<>(); List<CustomPartETag> customPartETags = RedisUtils.hget(redisKey, "customPartETags") == null ? new ArrayList<>() : JSON.parseArray((String) RedisUtils.hget(redisKey, "customPartETags"), CustomPartETag.class); //给前台提供是否缓存中已有数据 if(customPartETags.size()==0){ return m; }else{ //缓存中有数据,返回缓存中数据 int t= customPartETags.get(customPartETags.size()-1).getPartNumber(); m.put("key","hasValue"); m.put("value",t); return m; } }}3.远程的service
(如果不用远程调用，直接创建一个service就可以)
package com.geely.tcm.sheet.service; import com.baidubce.services.bos.BosClient;import com.baidubce.services.bos.model.*;import com.geely.tcm.common.bean.baidu.BosResult;import com.geely.tcm.common.bean.baidu.CustomPartETag;import com.geely.tcm.common.util.StringUtils;import com.geely.tcom.remote.api.baidu.BaiduCloudBosService;import lombok.extern.slf4j.Slf4j;import org.apache.dubbo.config.annotation.DubboService;import org.springframework.beans.factory.annotation.Autowired; import java.io.*;import java.net.URL;import java.util.ArrayList;import java.util.List; @Slf4j@DubboService(version = "${sheet.service.version}")public class BaiduCloudBosServiceImpl{ @Autowired private BosClient bosClient; public String initMultipartUpload(String filePath) { // 开始Multipart Upload InitiateMultipartUploadRequest initiateMultipartUploadRequest = new InitiateMultipartUploadRequest(null, filePath); InitiateMultipartUploadResponse initiateMultipartUploadResponse = bosClient.initiateMultipartUpload(initiateMultipartUploadRequest); // 打印UploadId，它是区分分块上传事件的唯一标识 String uploadId = initiateMultipartUploadResponse.getUploadId(); log.info("filePath= {},uploadId = {}", filePath, uploadId); return uploadId; } public CustomPartETag uploadCustomPartETag(String uploadId, String filePath, byte[] file, long partSize, int partNumber) { UploadPartRequest uploadPartRequest = new UploadPartRequest(); uploadPartRequest.setBucketName(null); uploadPartRequest.setKey(filePath); uploadPartRequest.setUploadId(uploadId); InputStream input= new ByteArrayInputStream(file); uploadPartRequest.setInputStream(input); uploadPartRequest.setPartSize(partSize); uploadPartRequest.setPartNumber(partNumber ); uploadPartRequest.setMd5Digest(""); UploadPartResponse uploadPartResponse = bosClient.uploadPart(uploadPartRequest); PartETag partETag = uploadPartResponse.getPartETag(); CustomPartETag customPartETag = new CustomPartETag(); customPartETag.setETag(partETag.getETag()); customPartETag.setPartNumber(partETag.getPartNumber()); return customPartETag; } public void completePart(String uploadId, List<CustomPartETag> customPartETags, String filePath) { //for循环转一下 CustomPartETag 转PartETag if(customPartETags.size()>0){ List<PartETag> partETags=new ArrayList<>(); for(CustomPartETag c:customPartETags){ PartETag partETag=new PartETag(); partETag.setETag(c.getETag()); partETag.setPartNumber(c.getPartNumber()); partETags.add(partETag); } CompleteMultipartUploadRequest completeMultipartUploadRequest = new CompleteMultipartUploadRequest(null, filePath, uploadId, partETags); CompleteMultipartUploadResponse completeMultipartUploadResponse = bosClient.completeMultipartUpload(completeMultipartUploadRequest); log.info("完成分片上传 ， filePath = {},uploadId = {}, etag = {}", filePath, uploadId,completeMultipartUploadResponse.getETag()); } }}4.定义一个实体类
继承，实现序列化，（dubbo不序列化就会传不过去）
import com.baidubce.services.bos.model.PartETag;import java.io.Serializable; public class CustomPartETag extends PartETag implements Serializable {}5.这里提供一个临时测试的前端代码
<html lang="en"><head> <meta charset="UTF-8"> <title>upload</title> <script src="https://cdn.bootcss.com/jquery/3.2.1/jquery.min.js"></script></head><body> <input type="file" name="file" id="file"> <button id="upload" onClick="upload()">upload</button> <script type="text/javascript"> var bytesPerPiece = 1024 * 1024; // 每个文件切片大小定为1MB . var totalPieces; function upload() { var blob = document.getElementById("file").files[0]; var start = 0; var end; var index = 1; var filesize = blob.size; var filename = blob.name; //计算文件切片总数 totalPieces = Math.ceil(filesize / bytesPerPiece); while(start < filesize) { end = start + bytesPerPiece; if(end > filesize) { end = filesize; } var chunk = blob.slice(start,end);//切割文件 var sliceIndex= blob.name + index; var formData = new FormData(); formData.append("file", chunk, filename); formData.append("totalSize",filesize); formData.append("chunks",totalPieces); formData.append("chunk",index); formData.append("model",'kx11'); $.ajax({//路径换成你的路径 url: 'http://127.0.0.1:6300/threeModel/upload3DToBos', type: 'POST', dataType:'json', cache: false, data: formData, processData: false, contentType: false, mimeType: "multipart/form-data", success: function (result){ console.log(result.value); } }); start = end; index++; } } </script></body></html>以上是“java如何实现文件切片上传服务器+断点续传”这篇文章的所有内容，感谢各位的阅读！相信大家都有了一定的了解，希望分享的内容对大家有所帮助，如果还想学习更多知识，欢迎关注编程网行业资讯频道！
