依赖包

<!-- https://mvnrepository.com/artifact/org.apache.hadoop/hadoop-client -->
        <dependency>
            <groupId>org.apache.hadoop</groupId>
            <artifactId>hadoop-client</artifactId>
            <version>2.7.3</version>
        </dependency>

代码样例

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package com.lys.app.oozie;

import java.net.URI;

import org.apache.hadoop.fs.*;
import org.apache.hadoop.conf.Configuration;

/**
 * @Auther: liuysh
 * @Date: 2020/12/1 16:23
 * @Description: http://node223.xdata:50070/explorer.html#/test/lys
 */
public class HdfsUtils {

    public static FileSystem getFileSystem() throws Exception{
        Configuration conf = new Configuration();
        conf.set("fs.hdfs.impl", "org.apache.hadoop.hdfs.DistributedFileSystem");
//        conf.set("fs.defaultFS", "hdfs://node223.xdata:8020");
        FileSystem fileSystem= FileSystem.get(new URI("hdfs://node223.xdata:8020"), conf, "hdfs");
        return fileSystem;
    }



    public static void mkDir(String path) throws Exception{
        FileSystem fileSystem=getFileSystem();
        Path dirHdfsPath = new Path(path);
        if (!fileSystem.exists(dirHdfsPath))
            fileSystem.mkdirs(dirHdfsPath);

    }


    public static void write(String path, String content) throws Exception{
        write(path, content.getBytes());
    }

    public static void write(String path, byte[] file) throws Exception {
        FileSystem fs = getFileSystem();
        FSDataOutputStream outputStream = null;

        String dirPath = path.substring(0, path.lastIndexOf("/"));
        Path dirHdfsPath = new Path(dirPath);
        if (!fs.exists(dirHdfsPath))
            fs.mkdirs(dirHdfsPath);
        outputStream = fs.create(new Path(path));
        outputStream.write(file);

    }


    public static void copyFromLocalFile(Path src, Path dst) throws Exception {
        FileSystem fs = getFileSystem();
        fs.copyFromLocalFile(src,dst);

    }

    public static void copyToLocalFile(Path src, Path dst) throws Exception {
        FileSystem fs = getFileSystem();
        // 第一个false表示不会删除源文件, 第二个true表示使用本地文件系统
        fs.copyToLocalFile(false,src,dst,true);

    }


    private static void list(Path path) throws Exception {
        FileSystem fs = getFileSystem();
        FileStatus[] fileStatuses = fs.listStatus(path);
        for (FileStatus file:fileStatuses
        ) {
            if(file.isFile()){
                System.out.println(file.getPath().toString());
            }else{
                System.out.println(file.getPath().toString());
                list(file.getPath());
            }
        }
        fs.close();
    }



    public static void main(String[] args) throws Exception{
        mkDir("/test/lys");
        write("/test/lys/20201202.sql","show tables;");



        copyToLocalFile(new Path("/test/lys/shell/VGG.pdf"),new Path("E:\\person_management\\hdfs001\\VGG.pdf"));

        list(new Path("/test"));

    }
}