hadoop学习笔记4：java实现hdfs -ls/-lsr

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作业1：java代码实现hadoop fs -lsr的功能，调用FileSystem.listStatus(...)方法，显示结果，要求结果显示样式如hadoop fs -ls xxx的结果类似。

作业2：java 代码实现 hadoop fs -lsr 的功能

------上面两题的代码如下：

package hdfs;

import java.io.IOException;

import java.net.URI;

import java.net.URISyntaxException;

import org.apache.commons.lang.time.DateFormatUtils;

import org.apache.hadoop.conf.Configuration;

import org.apache.hadoop.fs.FileStatus;

import org.apache.hadoop.fs.FileSystem;

import org.apache.hadoop.fs.Path;

public class TestFIleSystem {

public static void main(String[] args) throws IOException,

URISyntaxException {

final FileSystem fs = FileSystem.get( new URI("hdfs://chaoren1:9012" ),

new Configuration());

FileStatus[] listStatus = fs.listStatus( new Path("/" ));

// java代码实现hadoop fs - lsr的功能，调用FileSystem.listStatus(...)方法，显示结果，要求结果显示样式如 hadoop fs -ls xxx的结果类似。

//ls (fs);

// java 代码实现 hadoop fs - lsr 的功能

lsr(fs, listStatus);

}

private static void lsr(FileSystem fs, FileStatus[] listStatus)

throws IOException {

for (FileStatus fileStatus : listStatus) {

// 判断是否是文件夹

final boolean isdir = fileStatus.isDir();

final String permission = fileStatus.getPermission().toString();

final short replication = fileStatus.getReplication();

final String group = fileStatus.getGroup().toString();

final String owner = fileStatus.getOwner().toString();

final long blockSize = fileStatus.getBlockSize();

final String modificationTime = DateFormatUtils.format (

fileStatus.getModificationTime(), "yyyy-MM-dd HH:mm:ss");

final String path = fileStatus.getPath().toString();

final String substringPath = path.substring(20, path.length());

System. out.println((isdir ? "d" : "-" )+ permission + " "

+ (replication > 0 ? replication : "-").toString() + " "

+ owner + " " + group + " " + blockSize + "\t\t"

+ modificationTime + " " + substringPath);

if (isdir) {

lsr(fs, fs.listStatus(fileStatus.getPath()));

}

private static void ls( final FileSystem fs) throws IOException {

final FileStatus[] listStatus = fs.listStatus(new Path( "/"));