Java programs operate HDFS

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Decompression-2.7.3.tar.gz hadoop
E: \ tools \ big data \ big data to enhance data \ 01- software data \ 06-Hadoop \ installer \ Java1.8 environment
compiled under \ hadoop-2.7.3 \ hadoop- 2.7.3 \ report this content share \ hadoop \ the Common
E: \ tools \ big data \ big data to enhance data \ 01- software data \ 06-Hadoop \ installer \ Java1.8 environment
compiled under \ hadoop-2.7.3 \ hadoop-2.7 .3 \ report this content share \ \ the Common \ lib hadoop
E: \ tools \ big data \ big data to enhance data \ 01- software data \ 06-Hadoop \ installer \ Java1.8 environment
compiled under \ hadoop-2.7.3 \ hadoop- 2.7.3 \ share \ hadoop \ hdfs

JUNIT unit testing
  / **
   * unit test
   * 1. modifier must be public
   * not have parameters 2.
   * 3. not have a return value
   *
   * Run: Select the name of the method to run
   * RUN AS-JUnit Test
   * /
  @Test
  void M1 public () {
    System.out.println ( "Hello");
  }

package com.zy.hdfs;

import java.io.IOException;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Iterator;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.LocatedFileStatus;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.RemoteIterator;
import org.junit.Before;
import org.junit.Test;

public class test {
    public static  void main (String [] args) throws Exception {
         // upload 
        
        // 1 Examples of Configuration 
        the Configuration Configuration = new new the Configuration ();
         // -------------------
         // set properties 
        configuration.set ( "dfs.replication", "2"); // 2 copies 
        configuration.set ( "dfs.blocksize", "80m"); // in accordance 80m segmentation
         // - --------------------
         // 2. obtain the file system operation client instance 
        the fileSystem FileSystem.get FS = ( new new the URI ( "HDFS: //192.168.64.111 : 9000 / "), configuration, " root ");
         // 3. Perform the upload operation (src local resources, dst upload destination) 
        fs.copyFromLocalFile ( new new Path ( "C: \\ the Users Desktop \\ \\ \\ wc.txt Administrator"), new new Path ( " / ")); // twice as upload will be covered
         // Close the link 
        fs.Close (); 
    } 
    
    

    @Test 
    public  void downloads () throws Exception {
         // download 
        
        the Configuration Configuration = new new the Configuration (); 
        
        the FileSystem FS = FileSystem.get ( new new the URI ( "HDFS: //192.168.64.111: 9000"), Configuration, "the root" );
        
        fs.copyToLocalFile(false, new Path("/jdk-8u141-linux-x64.tar.gz"), new Path("E://jdk-8u141-linux-x64.tar.gz"), true);
        
        fs.close();    
        
    }
    //----------------
    FileSystem fs=null;
    @Before//在每次运行junit时先执行
    public void before() throws Exception{
        System.out.println("11111");
        Configuration configuration = new Configuration();    
        fs = FileSystem.get(newThe URI ( "HDFS: //192.168.64.111: 9000 /"), Configuration, "the root" );         
    } 
    // --------------- 
    @Test
     public  void Delete () throws Exception { // delete 
        fs.delete ( new new Path ( "/ elastic expression .doc"), true ); // to true to delete the folder and the contents inside, false can only delete empty folders 
        fs.close (); 
        
    } 
    @Test 
    public  void mkdir () throws Exception { // create a directory 
        fs.mkdirs ( new new the Path ( "/ A / B / C" )); 
        fs.Close (); 
        
    }
    
    @Test
    public void list() throws Exception{
        FileStatus[] listStatus = fs.listStatus(new Path("/"));//不会递归进去
        for (FileStatus fileStatus : listStatus) {
            if(fileStatus.isFile()){
                System.out.println("文件名:"+fileStatus.getPath().toString());
                
            }else{
                System.out.println("目录:"+fileStatus.getPath().toString());
                
            }
            
        }
        fs.close();
        
    }
    @Test
    public voidList2 () throws Exception { // recursive traversal of all files 
        RemoteIterator <LocatedFileStatus> = fs.listFiles the listFiles ( new new the Path ( "/"), to true ); // true, the recurse 
        the while (listFiles.hasNext ()) { 
            Next LocatedFileStatus = listFiles.next (); 
            System.out.println (next.toString ()); 
            System.out.println ( "file block size" + next.getBlockSize ()); 
         
        } 

    } 
 
}