查詢某個檔案在HDFS叢集中的位置
阿新 • • 發佈：2018-12-21
package com.njupt.hadoop;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.fs.BlockLocation;import org.apache.hadoop.fs.FileStatus;import org.apache.hadoop.fs.FileSystem;import org.apache.hadoop.fs.Path;import org.apache.hadoop.hdfs.DistributedFileSystem;import org.apache.hadoop.hdfs.protocol.DatanodeInfo;public class FindFileOnHDFS {public static void main(String[] args) throws Exception{getHDFSNodes();getFileLocal();}public static void getFileLocal() throws Exception {Configuration conf = new Configuration();FileSystem hdfs = FileSystem.get(conf);Path fpath = new Path("/user/root/20120722/word.txt");FileStatus fileStatus = hdfs.getFileStatus(fpath); BlockLocation[] blkLocations = hdfs.getFileBlockLocations(fileStatus, 0, fileStatus.getLen()); int blockLen = blkLocations.length; for(int i = 0 ; i < blockLen ; ++i ){ String[] hosts = blkLocations[i].getHosts(); System.out.println("block_"+i + "_location:" + hosts[i]); }}public static void getHDFSNodes() throws Exception{Configuration conf = new Configuration();FileSystem fs = FileSystem.get(conf);DistributedFileSystem hdfs = (DistributedFileSystem)fs;DatanodeInfo[] dataNodeStats = hdfs.getDataNodeStats();for( int i = 0 ; i < dataNodeStats.length ; ++i ){System.out.println("DataNode_" + i + "_Node:" + dataNodeStats[i].getHostName());}}}