运行Hadoop权威指南中的例子：3.5.3：FileCopyWithProgress
1、编写代码：package crt.hadoop.test;
import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;
import org.apache.hadoop.conf.Configuration;
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 {
/**
* @param args
*/
public static void main(String[] args) throws Exception{
// TODO Auto-generated method stub
String localSrc = args;
String dst = args;
InputStream in = new BufferedInputStream(new FileInputStream(localSrc));
Configuration conf = new Configuration();
FileSystem fs = FileSystem.get(URI.create(dst), conf);
OutputStream out = fs.create(new Path(dst), new Progressable(){
public void progress(){
System.out.print(".");
}
});
IOUtils.copyBytes(in, out, 4096, true);
}
}
2、复制FileCopyWithProgress.java到$HADOOP_HOME/build/classes
3、建测试文件
$ cd /home/hadoop/workspace/
$ mkdir writedata
$ cd writedata
$ mkdir input
$ cd input
$ cp -a /home/hadoop/workspace/writedata/crt/hadoop/test/FileCopyWithProgress.java ./writdatatestinput.txt
4、编译
$ javac -classpath $HADOOP_HOME/hadoop-common-0.21.0.jar
$HADOOP_HOME/build/classes/crt/hadoop/test/FileCopyWithProgress.java
5、运行
$ export HADOOP_CLASSPATH=build/classes
$ cd /home/hadoop/workspace/writedata/input
$ hadoop crt.hadoop.test.FileCopyWithProgress writedatatestinput.txt
hdfs://hadoop-namenode:9001/tmp/writedatatestinput.txt
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