package com.css.hdfs04;import java.io.File;import java.io.FileInputStream;import java.io.FileOutputStream;import java.io.IOException;import java.net.URI;import java.net.URISyntaxException;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.fs.FSDataInputStream;import org.apache.hadoop.fs.FSDataOutputStream;import org.apache.hadoop.fs.FileSystem;import org.apache.hadoop.fs.Path;import org.apache.hadoop.io.IOUtils;import org.junit.Before;import org.junit.Test;/** * IOUtils方式上传下载文件 */public class HdfsIo { ???Configuration conf = null; ???FileSystem fs =null; ???@Before ???public void init() throws IOException, InterruptedException, URISyntaxException { ???????// 1.加载配置 ???????conf = new Configuration(); ???????// 2.构造客户端 ???????fs = FileSystem.get(new URI("hdfs://192.168.146.132:9000/"), conf, "root"); ???} ???????/** ????* 文件上传HDFS ????*/ ???@Test ???public void putFileToHDFS() throws IllegalArgumentException, IOException{ ???????// 1.获取输入流 ???????FileInputStream fis = new FileInputStream(new File("c:/hello.txt")); ???????// 2.获取输出流 ???????FSDataOutputStream fos = fs.create(new Path("/hello.txt")); ???????// 3.流的拷贝 ???????IOUtils.copyBytes(fis, fos, conf); ???????// 4.关闭资源 ???????IOUtils.closeStream(fis); ???????IOUtils.closeStream(fos); ???} ???????/** ????* 文件下载HDFS ????*/ ???@Test ???public void getFileFromHDFS() throws IllegalArgumentException, IOException{ ???????// 1.获取输入流 ???????FSDataInputStream fis = fs.open(new Path("/hello")); ???????// 2.获取输出流 ???????FileOutputStream fos = new FileOutputStream(new File("c:/hello")); ???????// 3.流的对拷 ???????IOUtils.copyBytes(fis, fos, conf); ???????// 4.关闭资源 ???????IOUtils.closeStream(fis); ???????IOUtils.closeStream(fos); ???}}IOUtils方式上传下载文件
原文地址：https://www.cnblogs.com/areyouready/p/9795442.html