用java程序把本地的一个文件拷贝到hdfs上并显示进度

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把程序打成jar包放到Linux上
转到目录下执行命令 hadoop jar mapreducer.jar /home/clq/export/java/count.jar hdfs://ubuntu:9000/out06/count/
上面一个是本地文件，一个是上传hdfs位置

成功后出现：打印出来，你所要打印的字符。

package com.clq.hdfs;import java.io.BufferedInputStream;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.net.URI;import org.apache.hadoop.conf.Configuration;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.apache.hadoop.util.Progressable;public class FileCopyWithProgress {//********************************//把本地的一个文件拷贝到hdfs上//********************************public static void main(String[] args) throws IOException {String localSrc = args[0];String dst = args[1];InputStream in = new BufferedInputStream(new FileInputStream(localSrc));Configuration conf = new Configuration();FileSystem fs = FileSystem.get(URI.create(dst), conf);FSDataOutputStream out = fs.create(new Path(dst), new Progressable() {@Overridepublic void progress() {System.out.print(".");}});IOUtils.copyBytes(in, out, conf, true);}}

可能出现异常：
Exception in thread "main" org.apache.hadoop.ipc.RemoteException: java.io.IOException: Cannot create /out06; already exists as a directory
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFileInternal(FSNamesystem.java:1569)
at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.startFile(FSNamesystem.java:1527)
at org.apache.hadoop.hdfs.server.namenode.NameNode.create(NameNode.java:710)
at org.apache.hadoop.hdfs.server.namenode.NameNode.create(NameNode.java:689)
at sun.reflect.GeneratedMethodAccessor7.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.hadoop.ipc.RPC$Server.call(RPC.java:587)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1432)
at org.apache.hadoop.ipc.Server$Handler$1.run(Server.java:1428)
at java.security.AccessController.doPrivileged(Native Method)
at javax.security.auth.Subject.doAs(Subject.java:415)
说明你这个路径在hdfs上已经存在，换一个即可。

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