hadoop - hadoop2.6 伪分布式 - Java API 操作 HDFS

1.环境

   hadoop 2.6 

   hdfs 地址 ： hdfs://localhost:9000

  开发环境 ： eclipse 

 新建Map/Reduce 工程

2.代码示例

package cn.labelnet.demo;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
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;

public class UrlTest {

private static final String HDFS_URL="hdfs://localhost:9000";

private static final String DIR_URL="/zhuo";

private static final String FILE_URL="/zhuo/yuan";

private static final String FILE1_URL="/ming";

public static void main(String[] args) throws Exception {
FileSystem fs = FileSystem.get(new URI(HDFS_URL),new Configuration());

// createDir(fs);
// upfile(fs);

// downFile(fs);

// deleteFIle(fs);

deleteDir(fs);
}

private static void deleteDir(FileSystem fs) throws IOException {
//删除文件夹
boolean g = fs.delete(new Path(DIR_URL),true);
System.out.println(g);
}

private static void deleteFIle(FileSystem fs) throws IOException {
//删除文件
boolean b = fs.delete(new Path(FILE1_URL), true);
System.out.println(b);
}

private static void downFile(FileSystem fs) throws IOException {
//下载文件
FSDataInputStream fis = fs.open(new Path(FILE_URL));
IOUtils.copyBytes(fis, System.out,1024,true);
}

private static void createDir(FileSystem fs) throws IOException {
//创建文件夹
fs.mkdirs(new Path(DIR_URL));
}

private static void upfile(FileSystem fs) throws FileNotFoundException, IOException {
FileInputStream in=new FileInputStream("yuan.txt");
//上传文件
FSDataOutputStream fos = fs.create(new Path(FILE_URL),true);
IOUtils.copyBytes(in, fos, 1024,true);
}

}

3.Demo 免积分下载

http://download.csdn.net/detail/lablenet/9414924