HDFS的Java客户端操作代码(查看HDFS下所有的文件存储位置信息)详解大数据

 1 package Hdfs; 
 2  
 3 import java.net.URI; 
 4 import org.apache.hadoop.conf.Configuration; 
 5 import org.apache.hadoop.fs.BlockLocation; 
 6 import org.apache.hadoop.fs.FileStatus; 
 7 import org.apache.hadoop.fs.FileSystem; 
 8 import org.apache.hadoop.fs.Path; 
 9  
10 public class LocationFile { 
11     public static void main(String[] args) throws Exception { 
12         String uri = "hdfs://neusoft-master:9000/user/root/test/demo1"; 
13         Configuration conf = new Configuration(); 
14         try { 
15             FileSystem fs = FileSystem.get(URI.create(uri), conf); 
16             Path fpath = new Path(uri); 
17             FileStatus fileStatus = fs.getFileStatus(fpath); 
18             BlockLocation[] blockLocations = fs.getFileBlockLocations( 
19                     fileStatus, 0, fileStatus.getLen()); 
20             int blocklen = blockLocations.length; 
21             for (int i = 0; i < blocklen; i++) { 
22                 String[] hosts = blockLocations[i].getHosts(); 
23                 System.out.println("block_" +i+ "_location:" + hosts[0]); 
24             } 
25         } catch (Exception e) { 
26             e.printStackTrace(); 
27         } 
28     } 
29 }