SpringBoot集成Hadoop對HDFS的文件操作方法
更新時間：2024年07月11日 14:36:21 作者：碼學弟
這篇文章主要介紹了SpringBoot集成Hadoop對HDFS的文件操作方法,本文給大家介紹的非常詳細,感興趣的朋友跟隨小編一起看看吧
一、對HDFS操作設計以下幾個主要的類：
Configuration：封裝了客戶端或者服務器的配置信息；
FileSystem：此類的對象是一個文件系統(tǒng)對象，可以用該對象的一些方法來對文件進行操作通過FileSystem的靜態(tài)方法get獲得該對象，例：FileSystem hdfs = FileSystem.get(conf)；
FSDataInputStream：這是HDFS中的輸入流，通過由FileSystem的open方法獲?。?/p>
FSDataOutputStream：這是HDFS中的輸出流，通過由FileSystem的create方法獲取。
二、依賴配置
Maven
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.hdfs</groupId>
<artifactId>HadoopTest</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>HadoopTest</name>
<url>http://maven.apache.org</url>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.0.RELEASE</version>
<relativePath />
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-common</artifactId>
<version>3.1.1</version>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-hdfs</artifactId>
<version>3.1.1</version>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-client</artifactId>
<version>3.1.1</version>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-mapreduce-client-core</artifactId>
<version>3.1.1</version>
</dependency>
<dependency>
<groupId>cn.bestwu</groupId>
<artifactId>ik-analyzers</artifactId>
<version>5.1.0</version>
</dependency>
<dependency>
<groupId>jdk.tools</groupId>
<artifactId>jdk.tools</artifactId>
<version>1.8</version>
<scope>system</scope>
<systemPath>${JAVA_HOME}/lib/tools.jar</systemPath>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>Application.properties
# tomcat thread = 200 server.tomcat.max-threads=1000 # edit tomcat port server.port=8900 # session time 30 server.session-timeout=60 spring.application.name=hadoop spring.servlet.multipart.max-file-size=50MB spring.servlet.multipart.max-request-size=50MB hdfs.path=hdfs://localhost:9000 hdfs.username=linhaiy logging.config=classpath:logback.xml
三、HDFS文件操作接口開發(fā)
Config
package com.hadoop.config;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Configuration;
/**
* HDFS配置類
* @author linhaiy
* @date 2019.05.18
*/
@Configuration
public class HdfsConfig {
@Value("${hdfs.path}")
private String path;
public String getPath() {
return path;
}
public void setPath(String path) {
this.path = path;
}
}Entity
package com.hadoop.hdfs.entity;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import org.apache.hadoop.io.Writable;
/**
* 用戶實體類
* @author linhaiy
* @date 2019.05.18
*/
public class User implements Writable {
private String username;
private Integer age;
private String address;
public User() {
super();
// TODO Auto-generated constructor stub
}
public User(String username, Integer age, String address) {
super();
this.username = username;
this.age = age;
this.address = address;
}
@Override
public void write(DataOutput output) throws IOException {
// 把對象序列化
output.writeChars(username);
output.writeInt(age);
output.writeChars(address);
}
@Override
public void readFields(DataInput input) throws IOException {
// 把序列化的對象讀取到內(nèi)存中
username = input.readUTF();
age = input.readInt();
address = input.readUTF();
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "User [username=" + username + ", age=" + age + ", address=" + address + "]";
}
}Service
package com.hadoop.hdfs.service;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URI;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.annotation.PostConstruct;
import org.apache.commons.lang.StringUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.BlockLocation;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.LocatedFileStatus;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.RemoteIterator;
import org.apache.hadoop.io.IOUtils;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.web.multipart.MultipartFile;
import com.hadoop.util.JsonUtil;
@Component
public class HdfsService {
@Value("${hdfs.path}")
private String path;
@Value("${hdfs.username}")
private String username;
private static String hdfsPath;
private static String hdfsName;
private static final int bufferSize = 1024 * 1024 * 64;
/**
* 獲取HDFS配置信息
* @return
*/
private static Configuration getConfiguration() {
Configuration configuration = new Configuration();
configuration.set("fs.defaultFS", hdfsPath);
return configuration;
}
/**
* 獲取HDFS文件系統(tǒng)對象
* @return
* @throws Exception
*/
public static FileSystem getFileSystem() throws Exception {
// 客戶端去操作hdfs時是有一個用戶身份的，默認情況下hdfs客戶端api會從jvm中獲取一個參數(shù)作為自己的用戶身份
// DHADOOP_USER_NAME=hadoop
// 也可以在構(gòu)造客戶端fs對象時，通過參數(shù)傳遞進去
FileSystem fileSystem = FileSystem.get(new URI(hdfsPath), getConfiguration(), hdfsName);
return fileSystem;
}
/**
* 在HDFS創(chuàng)建文件夾
* @param path
* @return
* @throws Exception
*/
public static boolean mkdir(String path) throws Exception {
if (StringUtils.isEmpty(path)) {
return false;
}
if (existFile(path)) {
return true;
}
FileSystem fs = getFileSystem();
// 目標路徑
Path srcPath = new Path(path);
boolean isOk = fs.mkdirs(srcPath);
fs.close();
return isOk;
}
/**
* 判斷HDFS文件是否存在
* @param path
* @return
* @throws Exception
*/
public static boolean existFile(String path) throws Exception {
if (StringUtils.isEmpty(path)) {
return false;
}
FileSystem fs = getFileSystem();
Path srcPath = new Path(path);
boolean isExists = fs.exists(srcPath);
return isExists;
}
/**
* 讀取HDFS目錄信息
* @param path
* @return
* @throws Exception
*/
public static List<Map<String, Object>> readPathInfo(String path) throws Exception {
if (StringUtils.isEmpty(path)) {
return null;
}
if (!existFile(path)) {
return null;
}
FileSystem fs = getFileSystem();
// 目標路徑
Path newPath = new Path(path);
FileStatus[] statusList = fs.listStatus(newPath);
List<Map<String, Object>> list = new ArrayList<>();
if (null != statusList && statusList.length > 0) {
for (FileStatus fileStatus : statusList) {
Map<String, Object> map = new HashMap<>();
map.put("filePath", fileStatus.getPath());
map.put("fileStatus", fileStatus.toString());
list.add(map);
}
return list;
} else {
return null;
}
}
/**
* HDFS創(chuàng)建文件
* @param path
* @param file
* @throws Exception
*/
public static void createFile(String path, MultipartFile file) throws Exception {
if (StringUtils.isEmpty(path) || null == file.getBytes()) {
return;
}
String fileName = file.getOriginalFilename();
FileSystem fs = getFileSystem();
// 上傳時默認當前目錄，后面自動拼接文件的目錄
Path newPath = new Path(path + "/" + fileName);
// 打開一個輸出流
FSDataOutputStream outputStream = fs.create(newPath);
outputStream.write(file.getBytes());
outputStream.close();
fs.close();
}
/**
* 讀取HDFS文件內(nèi)容
* @param path
* @return
* @throws Exception
*/
public static String readFile(String path) throws Exception {
if (StringUtils.isEmpty(path)) {
return null;
}
if (!existFile(path)) {
return null;
}
FileSystem fs = getFileSystem();
// 目標路徑
Path srcPath = new Path(path);
FSDataInputStream inputStream = null;
try {
inputStream = fs.open(srcPath);
// 防止中文亂碼
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
String lineTxt = "";
StringBuffer sb = new StringBuffer();
while ((lineTxt = reader.readLine()) != null) {
sb.append(lineTxt);
}
return sb.toString();
} finally {
inputStream.close();
fs.close();
}
}
/**
* 讀取HDFS文件列表
* @param path
* @return
* @throws Exception
*/
public static List<Map<String, String>> listFile(String path) throws Exception {
if (StringUtils.isEmpty(path)) {
return null;
}
if (!existFile(path)) {
return null;
}
FileSystem fs = getFileSystem();
// 目標路徑
Path srcPath = new Path(path);
// 遞歸找到所有文件
RemoteIterator<LocatedFileStatus> filesList = fs.listFiles(srcPath, true);
List<Map<String, String>> returnList = new ArrayList<>();
while (filesList.hasNext()) {
LocatedFileStatus next = filesList.next();
String fileName = next.getPath().getName();
Path filePath = next.getPath();
Map<String, String> map = new HashMap<>();
map.put("fileName", fileName);
map.put("filePath", filePath.toString());
returnList.add(map);
}
fs.close();
return returnList;
}
/**
* HDFS重命名文件
* @param oldName
* @param newName
* @return
* @throws Exception
*/
public static boolean renameFile(String oldName, String newName) throws Exception {
if (StringUtils.isEmpty(oldName) || StringUtils.isEmpty(newName)) {
return false;
}
FileSystem fs = getFileSystem();
// 原文件目標路徑
Path oldPath = new Path(oldName);
// 重命名目標路徑
Path newPath = new Path(newName);
boolean isOk = fs.rename(oldPath, newPath);
fs.close();
return isOk;
}
/**
* 刪除HDFS文件
* @param path
* @return
* @throws Exception
*/
public static boolean deleteFile(String path) throws Exception {
if (StringUtils.isEmpty(path)) {
return false;
}
if (!existFile(path)) {
return false;
}
FileSystem fs = getFileSystem();
Path srcPath = new Path(path);
boolean isOk = fs.deleteOnExit(srcPath);
fs.close();
return isOk;
}
/**
* 上傳HDFS文件
* @param path
* @param uploadPath
* @throws Exception
*/
public static void uploadFile(String path, String uploadPath) throws Exception {
if (StringUtils.isEmpty(path) || StringUtils.isEmpty(uploadPath)) {
return;
}
FileSystem fs = getFileSystem();
// 上傳路徑
Path clientPath = new Path(path);
// 目標路徑
Path serverPath = new Path(uploadPath);
// 調(diào)用文件系統(tǒng)的文件復制方法，第一個參數(shù)是否刪除原文件true為刪除，默認為false
fs.copyFromLocalFile(false, clientPath, serverPath);
fs.close();
}
/**
* 下載HDFS文件
* @param path
* @param downloadPath
* @throws Exception
*/
public static void downloadFile(String path, String downloadPath) throws Exception {
if (StringUtils.isEmpty(path) || StringUtils.isEmpty(downloadPath)) {
return;
}
FileSystem fs = getFileSystem();
// 上傳路徑
Path clientPath = new Path(path);
// 目標路徑
Path serverPath = new Path(downloadPath);
// 調(diào)用文件系統(tǒng)的文件復制方法，第一個參數(shù)是否刪除原文件true為刪除，默認為false
fs.copyToLocalFile(false, clientPath, serverPath);
fs.close();
}
/**
* HDFS文件復制
* @param sourcePath
* @param targetPath
* @throws Exception
*/
public static void copyFile(String sourcePath, String targetPath) throws Exception {
if (StringUtils.isEmpty(sourcePath) || StringUtils.isEmpty(targetPath)) {
return;
}
FileSystem fs = getFileSystem();
// 原始文件路徑
Path oldPath = new Path(sourcePath);
// 目標路徑
Path newPath = new Path(targetPath);
FSDataInputStream inputStream = null;
FSDataOutputStream outputStream = null;
try {
inputStream = fs.open(oldPath);
outputStream = fs.create(newPath);
IOUtils.copyBytes(inputStream, outputStream, bufferSize, false);
} finally {
inputStream.close();
outputStream.close();
fs.close();
}
}
/**
* 打開HDFS上的文件并返回byte數(shù)組
* @param path
* @return
* @throws Exception
*/
public static byte[] openFileToBytes(String path) throws Exception {
if (StringUtils.isEmpty(path)) {
return null;
}
if (!existFile(path)) {
return null;
}
FileSystem fs = getFileSystem();
// 目標路徑
Path srcPath = new Path(path);
try {
FSDataInputStream inputStream = fs.open(srcPath);
return IOUtils.readFullyToByteArray(inputStream);
} finally {
fs.close();
}
}
/**
* 打開HDFS上的文件并返回java對象
* @param path
* @return
* @throws Exception
*/
public static <T extends Object> T openFileToObject(String path, Class<T> clazz) throws Exception {
if (StringUtils.isEmpty(path)) {
return null;
}
if (!existFile(path)) {
return null;
}
String jsonStr = readFile(path);
return JsonUtil.fromObject(jsonStr, clazz);
}
/**
* 獲取某個文件在HDFS的集群位置
* @param path
* @return
* @throws Exception
*/
public static BlockLocation[] getFileBlockLocations(String path) throws Exception {
if (StringUtils.isEmpty(path)) {
return null;
}
if (!existFile(path)) {
return null;
}
FileSystem fs = getFileSystem();
// 目標路徑
Path srcPath = new Path(path);
FileStatus fileStatus = fs.getFileStatus(srcPath);
return fs.getFileBlockLocations(fileStatus, 0, fileStatus.getLen());
}
@PostConstruct
public void getPath() {
hdfsPath = this.path;
}
@PostConstruct
public void getName() {
hdfsName = this.username;
}
public static String getHdfsPath() {
return hdfsPath;
}
public String getUsername() {
return username;
}
}Controller
package com.hadoop.hdfs.controller;
import java.util.List;
import java.util.Map;
import org.apache.commons.lang.StringUtils;
import org.apache.hadoop.fs.BlockLocation;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import com.hadoop.hdfs.entity.User;
import com.hadoop.hdfs.service.HdfsService;
import com.hadoop.util.Result;
@RestController
@RequestMapping("/hadoop/hdfs")
public class HdfsAction {
private static Logger LOGGER = LoggerFactory.getLogger(HdfsAction.class);
/**
* 創(chuàng)建文件夾
* @param path
* @return
* @throws Exception
*/
@RequestMapping(value = "mkdir", method = RequestMethod.POST)
@ResponseBody
public Result mkdir(@RequestParam("path") String path) throws Exception {
if (StringUtils.isEmpty(path)) {
LOGGER.debug("請求參數(shù)為空");
return new Result(Result.FAILURE, "請求參數(shù)為空");
}
// 創(chuàng)建空文件夾
boolean isOk = HdfsService.mkdir(path);
if (isOk) {
LOGGER.debug("文件夾創(chuàng)建成功");
return new Result(Result.SUCCESS, "文件夾創(chuàng)建成功");
} else {
LOGGER.debug("文件夾創(chuàng)建失敗");
return new Result(Result.FAILURE, "文件夾創(chuàng)建失敗");
}
}
/**
* 讀取HDFS目錄信息
* @param path
* @return
* @throws Exception
*/
@PostMapping("/readPathInfo")
public Result readPathInfo(@RequestParam("path") String path) throws Exception {
List<Map<String, Object>> list = HdfsService.readPathInfo(path);
return new Result(Result.SUCCESS, "讀取HDFS目錄信息成功", list);
}
/**
* 獲取HDFS文件在集群中的位置
* @param path
* @return
* @throws Exception
*/
@PostMapping("/getFileBlockLocations")
public Result getFileBlockLocations(@RequestParam("path") String path) throws Exception {
BlockLocation[] blockLocations = HdfsService.getFileBlockLocations(path);
return new Result(Result.SUCCESS, "獲取HDFS文件在集群中的位置", blockLocations);
}
/**
* 創(chuàng)建文件
* @param path
* @return
* @throws Exception
*/
@PostMapping("/createFile")
public Result createFile(@RequestParam("path") String path, @RequestParam("file") MultipartFile file)
throws Exception {
if (StringUtils.isEmpty(path) || null == file.getBytes()) {
return new Result(Result.FAILURE, "請求參數(shù)為空");
}
HdfsService.createFile(path, file);
return new Result(Result.SUCCESS, "創(chuàng)建文件成功");
}
/**
* 讀取HDFS文件內(nèi)容
* @param path
* @return
* @throws Exception
*/
@PostMapping("/readFile")
public Result readFile(@RequestParam("path") String path) throws Exception {
String targetPath = HdfsService.readFile(path);
return new Result(Result.SUCCESS, "讀取HDFS文件內(nèi)容", targetPath);
}
/**
* 讀取HDFS文件轉(zhuǎn)換成Byte類型
* @param path
* @return
* @throws Exception
*/
@PostMapping("/openFileToBytes")
public Result openFileToBytes(@RequestParam("path") String path) throws Exception {
byte[] files = HdfsService.openFileToBytes(path);
return new Result(Result.SUCCESS, "讀取HDFS文件轉(zhuǎn)換成Byte類型", files);
}
/**
* 讀取HDFS文件裝換成User對象
* @param path
* @return
* @throws Exception
*/
@PostMapping("/openFileToUser")
public Result openFileToUser(@RequestParam("path") String path) throws Exception {
User user = HdfsService.openFileToObject(path, User.class);
return new Result(Result.SUCCESS, "讀取HDFS文件裝換成User對象", user);
}
/**
* 讀取文件列表
* @param path
* @return
* @throws Exception
*/
@PostMapping("/listFile")
public Result listFile(@RequestParam("path") String path) throws Exception {
if (StringUtils.isEmpty(path)) {
return new Result(Result.FAILURE, "請求參數(shù)為空");
}
List<Map<String, String>> returnList = HdfsService.listFile(path);
return new Result(Result.SUCCESS, "讀取文件列表成功", returnList);
}
/**
* 重命名文件
* @param oldName
* @param newName
* @return
* @throws Exception
*/
@PostMapping("/renameFile")
public Result renameFile(@RequestParam("oldName") String oldName, @RequestParam("newName") String newName)
throws Exception {
if (StringUtils.isEmpty(oldName) || StringUtils.isEmpty(newName)) {
return new Result(Result.FAILURE, "請求參數(shù)為空");
}
boolean isOk = HdfsService.renameFile(oldName, newName);
if (isOk) {
return new Result(Result.SUCCESS, "文件重命名成功");
} else {
return new Result(Result.FAILURE, "文件重命名失敗");
}
}
/**
* 刪除文件
* @param path
* @return
* @throws Exception
*/
@PostMapping("/deleteFile")
public Result deleteFile(@RequestParam("path") String path) throws Exception {
boolean isOk = HdfsService.deleteFile(path);
if (isOk) {
return new Result(Result.SUCCESS, "delete file success");
} else {
return new Result(Result.FAILURE, "delete file fail");
}
}
/**
* 上傳文件
* @param path
* @param uploadPath
* @return
* @throws Exception
*/
@PostMapping("/uploadFile")
public Result uploadFile(@RequestParam("path") String path, @RequestParam("uploadPath") String uploadPath)
throws Exception {
HdfsService.uploadFile(path, uploadPath);
return new Result(Result.SUCCESS, "upload file success");
}
/**
* 下載文件
* @param path
* @param downloadPath
* @return
* @throws Exception
*/
@PostMapping("/downloadFile")
public Result downloadFile(@RequestParam("path") String path, @RequestParam("downloadPath") String downloadPath)
throws Exception {
HdfsService.downloadFile(path, downloadPath);
return new Result(Result.SUCCESS, "download file success");
}
/**
* HDFS文件復制
* @param sourcePath
* @param targetPath
* @return
* @throws Exception
*/
@PostMapping("/copyFile")
public Result copyFile(@RequestParam("sourcePath") String sourcePath, @RequestParam("targetPath") String targetPath)
throws Exception {
HdfsService.copyFile(sourcePath, targetPath);
return new Result(Result.SUCCESS, "copy file success");
}
/**
* 查看文件是否已存在
* @param path
* @return
* @throws Exception
*/
@PostMapping("/existFile")
public Result existFile(@RequestParam("path") String path) throws Exception {
boolean isExist = HdfsService.existFile(path);
return new Result(Result.SUCCESS, "file isExist: " + isExist);
}
}四、一些測試結(jié)果截圖
到此這篇關(guān)于SpringBoot集成Hadoop——對HDFS的文件操作的文章就介紹到這了,更多相關(guān)SpringBoot 操作HDFS內(nèi)容請搜索腳本之家以前的文章或繼續(xù)瀏覽下面的相關(guān)文章希望大家以后多多支持腳本之家！
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