hdfs java操作

一般操作都是shell命令，记一下java操作

package hdfs;

import java.io.FileInputStream;

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.fs.Trash;

import org.apache.hadoop.io.IOUtils;

public class HDFS{

public static void main(String[] args) throws Exception {

//http://www.baidu.com

final FileSystem fileSystem = FileSystem.get(new URI("hdfs://server4:9000"), new Configuration());

System.out.println("**************"+fileSystem.toString());

System.out.println("**************"+fileSystem.getClass());

//创建文件夹mkdirs

//fileSystem.mkdirs(new Path("mydir"));

//fileSystem.mkdirs(new Path("/dir2"), new FsPermission("111"));

//上传文件create

//final FSDataOutputStream out = fileSystem.create(new Path("/dir1/file1"), true, 1024000, (short)2, 1048576);

//final FileInputStream in = new FileInputStream("/root/Downloads/hello");

//IOUtils.copyBytes(in, out, 1024, true);

//final AtomicInteger writeBytes = new AtomicInteger(0);

//final FSDataOutputStream out = fileSystem.create(new Path("/dir1/file2"), new Progressable() {

//@Override

//public void progress() {

//System.out.println("WriteBytes = "+writeBytes.get());

//}

//});

//

//final FileInputStream in = new FileInputStream("/root/Downloads/hello");

//byte[] buffer = new byte[4];

//int readBytes = in.read(buffer);

//while(readBytes!=-1) {

//out.write(buffer);

//out.flush();

//out.hsync();

//writeBytes.addAndGet(readBytes);

//readBytes = in.read(buffer);

//}

//读取数据

//final FSDataInputStream in = fileSystem.open(new Path("/dir1/file1"));

//IOUtils.copyBytes(in, System.out, 1024, true);

//遍历

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

//for (FileStatus fileStatus : listStatus) {

//System.out.println(fileStatus);

//}

//获取工作目录

//fileSystem.getWorkingDirectory().toString();

//删除

final Trash trash = new Trash(fileSystem, fileSystem.getConf());

trash.moveToTrash(new Path("/dir1/file1"));

fileSystem.delete(new Path("/dir1/file1"), true);

}

}