本文主要是介绍hdfs java客户端使用，文件上传下载，预览的实现，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！
1. 环境部署
1.1 Linux hadoop集群搭建 Hadoop大数据集群搭建（超详细）_hadoop集群搭建-CSDN博客
1.2 windows hadoop util 安装
Hadoop——Windows系统下Hadoop单机环境搭建_hadoop windows开发环境搭建-CSDN博客
1.3 温馨提示，如果要使用java客户端的api，本地就必须需要安装hadoop才能调用，如果要脱离环境，可以使用WebHDFS，具体的可以搜索一下Hadoop REST API – WebHDFS
本项目是基于java客户端api实现的
2.Maven 配置
<dependency><groupId>cn.hutool</groupId><artifactId>hutool-all</artifactId><version>5.3.9</version></dependency><!-- hadoop --><dependency><groupId>org.apache.hadoop</groupId><artifactId>hadoop-client</artifactId><version>3.2.4</version></dependency><dependency><groupId>org.apache.hadoop</groupId><artifactId>hadoop-hdfs</artifactId><version>3.2.4</version></dependency><dependency><groupId>org.apache.hadoop</groupId><artifactId>hadoop-common</artifactId><version>3.2.4</version></dependency>3.hdfs java api 工具类
import org.apache.commons.lang3.StringUtils;
import org.apache.hadoop.fs.*;
import org.apache.hadoop.io.IOUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnBean;
import org.springframework.stereotype.Component;import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.text.SimpleDateFormat;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;/*** @author maple* @describe* @createTime 2024/05/12*/
@Component
@ConditionalOnBean(FileSystem.class)
public class HadoopTemplate {private static final Logger log = LoggerFactory.getLogger(HadoopConfig.class);@Autowiredprivate FileSystem fileSystem;public void uploadFile(String srcFile, String destPath) {copyFileToHDFS(false, true, srcFile, destPath);}public void uploadFile(boolean del, String srcFile, String destPath) {copyFileToHDFS(del, true, srcFile, destPath);}public void delDir(String path) {rmdir(path, null);}public void download(String fileName, String savePath) {getFile(fileName, savePath);}/*** 创建目录** @param filePath* @param create* @return*/public boolean existDir(String filePath, boolean create) throws IOException {boolean flag = false;if (StringUtils.isEmpty(filePath)) {throw new IllegalArgumentException("filePath不能为空");}Path path = new Path(filePath);if (create) {if (!fileSystem.exists(path)) {fileSystem.mkdirs(path);}}if (fileSystem.isDirectory(path)) {flag = true;}return flag;}/*** 创建目录** @param filePath* @return*/public boolean existFile(String filePath) throws IOException {if (StringUtils.isEmpty(filePath)) {throw new IllegalArgumentException("filePath不能为空");}Path path = new Path(filePath);return fileSystem.exists(path);}/*** 文件上传至 HDFS** @param delSrc 指是否删除源文件，true 为删除，默认为 false* @param overwrite* @param srcFile 源文件，上传文件路径* @param destPath hdfs的目的路径*/public void copyFileToHDFS(boolean delSrc, boolean overwrite, String srcFile, String destPath) {// 源文件路径是Linux下的路径，如果在 windows 下测试，需要改写为Windows下的路径，比如D://hadoop/djt/weibo.txtPath srcPath = new Path(srcFile);Path dstPath = new Path(destPath);// 实现文件上传try {// 获取FileSystem对象fileSystem.copyFromLocalFile(delSrc, overwrite, srcPath, dstPath);System.out.println(dstPath);} catch (IOException e) {log.error("", e);}}/*** 删除文件或者文件目录** @param path*/public void rmdir(String path, String fileName) {try {if (StringUtils.isNotBlank(fileName)) {path = path + "/" + fileName;}// 删除文件或者文件目录 delete(Path f) 此方法已经弃用fileSystem.delete(new Path(path), true);} catch (IllegalArgumentException | IOException e) {log.error("", e);}}/*** 从 HDFS 下载文件** @param hdfsFile* @param destPath 文件下载后,存放地址*/public void getFile(String hdfsFile, String destPath) {Path hdfsPath = new Path(hdfsFile);Path dstPath = new Path(destPath);try {// 下载hdfs上的文件fileSystem.copyToLocalFile(hdfsPath, dstPath);} catch (IOException e) {log.error("", e);}}public void writer(String destPath, InputStream in) {try {FSDataOutputStream out = fileSystem.create(new Path(destPath));IOUtils.copyBytes(in, out, fileSystem.getConf());} catch (IOException e) {e.printStackTrace();}}public void open(String destPath, OutputStream out) {FSDataInputStream in = null;try {in = fileSystem.open(new Path(destPath));IOUtils.copyBytes(in,out,4096,false);in.seek(0);IOUtils.copyBytes(in,out,4096,false);} catch (IOException e) {e.printStackTrace();} finally {IOUtils.closeStream(in);}}public String getFileExtension(String destPath) {Path path = new Path(destPath);FileStatus fileStatus = null;try {// 获取文件的状态信息fileStatus = fileSystem.getFileStatus(path);} catch (IOException e) {log.info("获取文件的状态信息 IOException? " + e);}// 检查是否是目录boolean isDir = fileStatus.isDirectory();log.info("Is directory? " + isDir);// 检查是否是文件boolean isFile = fileStatus.isFile();log.info("Is file? " + isFile);// 如果是文件，可以获取文件的扩展名if (isFile) {String fileName = path.getName();String fileExtension = fileName.substring(fileName.lastIndexOf('.') + 1);log.info("File extension: " + fileExtension);return fileExtension;}return "";}public static String getContentType(String destPath) throws IOException {Path hdfsPath = new Path(destPath);// 获取文件名String fileName = hdfsPath.getName();// 根据文件扩展名推断ContentType，这里只是一个简单的例子if (fileName.endsWith(".txt")) {return "text/plain";} else if (fileName.endsWith(".jpg")) {return "image/jpeg";} else if (fileName.endsWith(".png")) {return "image/png";} else {// 默认返回"application/octet-stream"return "application/octet-stream";}}//获取特定路径的所有文件public void getFileList(String path) throws IOException {SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");FileStatus[] fileStatuses = fileSystem.listStatus(new Path(path));for(FileStatus fileStatus: fileStatuses) {System.out.println(fileStatus.getPath().getName());System.out.println(format.format(fileStatus.getModificationTime()));if(fileStatus.isDirectory())System.out.println("目录");elseSystem.out.println("文件");}//排序，目录放前面，文件放后面//Collator collator = Collator.getInstance(Locale.CHINA);//fileList.sort((f1, f2) -> (collator.compare(f1.getType(), f2.getType())));//return System.out.println(format.format(fileStatus.getModificationTime()));;}/*** 多文件(文件夹)** @param cloudPath* cloudPath* @author liudz* @date 2020/6/8* @return 执行结果**/public OutputStream down(String cloudPath,ZipOutputStream zos,ByteArrayOutputStream out) {try {compress(cloudPath, zos, fileSystem);} catch (IOException e) {log.info("----error:{}----" + e.getMessage());}return out;}/*** 多文件(文件夹)** @param cloudPath* cloudPath* @author liudz* @date 2020/6/8* @return 执行结果**/public OutputStream down2(String cloudPath) {// 1获取对象ByteArrayOutputStream out = null;try {out = new ByteArrayOutputStream();ZipOutputStream zos = new ZipOutputStream(out);compress(cloudPath, zos, fileSystem);zos.close();} catch (IOException e) {log.info("----error:{}----" + e.getMessage());}return out;}/*** compress** @param baseDir* baseDir* @param zipOutputStream* zipOutputStream* @param fs* fs* @author liudz* @date 2020/6/8**/public void compress(String baseDir, ZipOutputStream zipOutputStream, FileSystem fs) throws IOException {try {FileStatus[] fileStatulist = fs.listStatus(new Path(baseDir));log.info("basedir = " + baseDir);String[] strs = baseDir.split("/");//lastName代表路径最后的单词String lastName = strs[strs.length - 1];for (int i = 0; i < fileStatulist.length; i++) {String name = fileStatulist[i].getPath().toString();name = name.substring(name.indexOf("/" + lastName));if (fileStatulist[i].isFile()) {Path path = fileStatulist[i].getPath();FSDataInputStream inputStream = fs.open(path);zipOutputStream.putNextEntry(new ZipEntry(name.substring(1)));IOUtils.copyBytes(inputStream, zipOutputStream, Integer.parseInt("1024"));inputStream.close();} else {zipOutputStream.putNextEntry(new ZipEntry(fileStatulist[i].getPath().getName() + "/"));log.info("fileStatulist[i].getPath().toString() = " + fileStatulist[i].getPath().toString());compress(fileStatulist[i].getPath().toString(), zipOutputStream, fs);}}} catch (IOException e) {log.info("----error:{}----" + e.getMessage());}}}4. 配置
/*** @author maple* @describe* @createTime 2024-05-01*/
@Configuration
public class HadoopConfig {private static final Logger log = LoggerFactory.getLogger(HadoopConfig.class);@Value("${hadoop.user}")private String user;@Value("${hadoop.password}")private String password;@Value("${hdfs.hdfs-site}")private String hdfsSite;@Value("${hdfs.core-site}")private String coreSite;@Bean("fileSystem")public FileSystem createFs() throws Exception {System.setProperty("HADOOP_USER_NAME", user);System.setProperty("HADOOP_USER_PASSWORD", password);//读取配置文件org.apache.hadoop.conf.Configuration conf = new org.apache.hadoop.conf.Configuration();
// conf.addResource(coreSite);
// conf.addResource(hdfsSite);conf.set("fs.defaultFS",hdfsSite);conf.set("fs.hdfs.impl", "org.apache.hadoop.hdfs.DistributedFileSystem");log.info("===============【hadoop configuration info start.】===============");log.info("【hadoop conf】: size:{}, {}", conf.size(), conf.toString());log.info("【fs.defaultFS】: {}", conf.get("fs.defaultFS"));log.info("【fs.hdfs.impl】: {}", conf.get("fs.hdfs.impl"));FileSystem fs = FileSystem.newInstance(conf);log.info("【fileSystem scheme】: {}", fs.getScheme());log.info("===============【hadoop configuration info end.】===============");return fs;}
}hadoop:user: user001password: ******hdfs:hdfs-site: hdfs://hadoop101:9000core-site:5.使用案例
上传文件
/*** 通用上传请求（单个）*/@PostMapping("/upload/{parentId}")@Transactionalpublic AjaxResult uploadFile(MultipartFile file,@PathVariable Long parentId) throws Exception{try{String extension = FileUploadUtils.getExtension(file);// 上传文件路径String filePath = RuoYiConfig.getProfile();// 获取当前用户本人的存储目录DiskStorage diskStorage = diskStorageService.selectDiskStorageByUserId(SecurityUtils.getUserId());if (Objects.isNull(diskStorage)) throw new ServiceException("未初始化存储空间");if (diskStorage.getTotalCapacity()-diskStorage.getUsedCapacity()<=0) throw new ServiceException("存储空间不足");if (parentId.equals(0L)) {filePath = filePath+"/"+diskStorage.getBaseDir();} else {DiskFile parentIdFile = diskFileService.selectDiskFileById(parentId);if (Objects.isNull(parentIdFile)) throw new ServiceException("父文件夹不存在");filePath = filePath+StringUtils.substringAfter(parentIdFile.getUrl(), Constants.HADOOP_PREFIX).replace("--","/");}diskSensitiveWordService.filterSensitiveWord(file.getOriginalFilename());DiskFile diskFile = new DiskFile();String fileName = RandomUtil.randomString(4)+"_"+file.getOriginalFilename();diskFile.setName(fileName);// 上传并返回新文件名称fileName = FileUploadUtils.upload(filePath,false, file,fileName);// 上传到hdfsString descPath = StringUtils.substringAfter(fileName, Constants.RESOURCE_PREFIX);
//把本地文件上传到hdfshadoopTemplate.copyFileToHDFS(true,true,RuoYiConfig.getProfile()+ StringUtils.substringAfter(fileName, Constants.RESOURCE_PREFIX), descPath);String url = serverConfig.getUrl() + Constants.HADOOP_PREFIX + descPath.replace("/","--");diskFile.setCreateId(getUserId());diskFile.setOldName(file.getOriginalFilename());diskFile.setIsDir(0);diskFile.setOrderNum(0);diskFile.setParentId(parentId);diskFile.setUrl(url.replace(serverConfig.getUrl(),""));diskFile.setSize(file.getSize());diskFile.setType(diskFileService.getType(extension));diskFileService.save(diskFile,diskStorage);AjaxResult ajax = AjaxResult.success();ajax.put("url", url);ajax.put("fileName", url.replace(serverConfig.getUrl(),""));ajax.put("newFileName", FileUtils.getName(fileName));ajax.put("originalFilename", file.getOriginalFilename());ajax.put("size", file.getSize());ajax.put("type", extension);return ajax;}catch (Exception e){return AjaxResult.error(e.getMessage());}}文件下载
/*** hadoop文件下载*/@GetMapping("/download/zip")public void hadoopDownload(DownloadBo downloadBo, HttpServletResponse response) {List<DiskFile> diskFiles;String dest = RuoYiConfig.getProfile()+"/";if (StringUtils.isNotEmpty(downloadBo.getUuid())&&StringUtils.isNotEmpty(downloadBo.getSecretKey())) {diskFiles = diskFileService.selectDiskFileListByIds(Arrays.stream(downloadBo.getIds().split(",")).map(String::trim).map(Long::valueOf).toArray(Long[]::new));dest = dest + downloadBo.getUuid();} else {diskFiles = diskFileService.selectDiskFileListByIds(Arrays.stream(downloadBo.getIds().split(",")).map(String::trim).map(Long::valueOf).toArray(Long[]::new),getUserId());dest = dest + RandomUtil.randomString(6);}String downloadPath = dest + ".zip";try {ByteArrayOutputStream out = null;try {out = new ByteArrayOutputStream();ZipOutputStream zos = new ZipOutputStream(out);for (int i = 0; i < diskFiles.size(); i++) {String path = StringUtils.substringAfter(diskFiles.get(i).getUrl(),Constants.HADOOP_PREFIX);// 本地资源路径path = path.replace("--","/");//从远程下载文件到本地hadoopTemplate.down(path,zos,out);}zos.close();} catch (Exception e) {log.debug("diskfile 从远程下载文件到本地报错: "+e);}// 调用zip方法进行压缩byte[] data = out.toByteArray();out.close();response.reset();response.addHeader("Access-Control-Allow-Origin", "*");response.addHeader("Access-Control-Expose-Headers", "Content-Disposition");response.setHeader("Content-Disposition", "attachment; filename=\"ruoyi.zip\"");response.addHeader("Content-Length", "" + data.length);response.setContentType("application/octet-stream; charset=UTF-8");IOUtils.write(data, response.getOutputStream());} catch (IOException e) {log.error("diskFile 下载文件失败", e);} finally {FileUtils.deleteFile(downloadPath);}}文件预览
import com.ruoyi.disk.HadoopTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.core.io.ByteArrayResource;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;import java.io.ByteArrayOutputStream;@Controller
@RequestMapping("/hadoop")
public class HadoopController {@Autowiredprivate HadoopTemplate hadoopTemplate;@Value("${hdfs.hdfs-site}")private String hdfsSite;@GetMapping("/{descPath}")public ResponseEntity<ByteArrayResource> preview(@PathVariable("descPath") String descPath) {ByteArrayOutputStream outputStream = new ByteArrayOutputStream();hadoopTemplate.open(descPath.replace("--", "/"), outputStream);String fileExtension = hadoopTemplate.getFileExtension(descPath.replace("--", "/"));byte[] byteArray = outputStream.toByteArray();// 创建字节数组资源ByteArrayResource resource = new ByteArrayResource(byteArray);// 设置响应头HttpHeaders headers = new HttpHeaders();switch (fileExtension) {case "png":headers.setContentType(MediaType.IMAGE_PNG);break;case "gif":headers.setContentType(MediaType.IMAGE_GIF);break;case "jpeg":headers.setContentType(MediaType.IMAGE_JPEG);break;default:headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);break;}// 返回字节数组资源作为响应return ResponseEntity.ok().headers(headers).contentLength(byteArray.length).body(resource);}}
6. 完整项目代码地址：netdisk: 在线网盘系统，有本存储版，和hadoop大数据hdfs分布式文件存储版本，使用了DFA算法，实现了文件夹的创建与修改，多级目录，很正常的文件夹一样，支持所有文件上传，并按文件类型分类，支持文件删除，回收站管理，恢复与彻底删除，支持公开分享和私密分享可自动生成提取码，设置过期时间或永久有效，支持图片，视频文件的预览，支持文件夹及文件的批量压缩下载
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