MapReduce的测试

 

 

package com.bjsxt.mr;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.BlockLocation;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IOUtils;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

public class test {
	Configuration conf;
	FileSystem fs;
	
	@Before
	public void conn() throws IOException{
		conf = new 	Configuration(true);
		fs = FileSystem.get(conf);		
	}
	
	@After
	public void close() throws IOException{
		fs.close();
	}
	
	@Test
	public void mkdir() throws IOException{
		
		Path dirs = new Path("/data");
		
		if(fs.exists(dirs )){
			fs.delete(dirs,true);
		}
		
		fs.mkdirs(dirs);
	}
	
	
	@Test
	public void upload() throws IOException{
		Path output = new Path("/data/sxt.txt");
		FSDataOutputStream out = fs.create(output );
		
		InputStream input = new BufferedInputStream(new FileInputStream(new File("c:\\nginx.txt")));
		
		IOUtils.copyBytes(input,out,conf,true);		
		
	}
	
	@Test
	public void blks() throws IOException{
		Path f = new Path("/user/root/test.txt");
		FileStatus file = fs.getFileStatus(f);
		BlockLocation[] blks = fs.getFileBlockLocations(file, 0, file.getLen());
	
		for (BlockLocation b : blks){
			System.out.println(b);
		}
		
		FSDataInputStream in = fs.open(f);
		System.out.println((char)in.readByte());
		System.out.println((char)in.readByte());
		System.out.println((char)in.readByte());
		System.out.println((char)in.readByte());
		//让指针转移到这个位置
		in.seek(1048576);
		System.out.println((char)in.readByte());
		System.out.println((char)in.readByte());
		System.out.println((char)in.readByte());
		System.out.println((char)in.readByte());
		System.out.println((char)in.readByte());
	}
	
}