fm.last.hadoop.tools.BlockFinder.java Source code

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Here is the source code for fm.last.hadoop.tools.BlockFinder.java

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/**
 * Copyright 2011 Last.fm
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package fm.last.hadoop.tools;

import static com.google.common.collect.Lists.newArrayList;
import static java.lang.System.out;

import java.io.IOException;
import java.util.List;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.DFSClient;
import org.apache.hadoop.hdfs.protocol.ClientProtocol;
import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
import org.apache.hadoop.hdfs.protocol.LocatedBlock;
import org.apache.hadoop.hdfs.protocol.LocatedBlocks;

import com.google.common.base.Joiner;

public class BlockFinder extends HadoopCommand {
    protected FileSystem fs;

    public BlockFinder(Configuration conf) throws IOException {
        super(conf);
        this.fs = FileSystem.get(getConf());
    }

    @Override
    public int run(String[] argv) throws IOException {
        StringBuilder b = new StringBuilder();

        ClientProtocol namenode = DFSClient.createNamenode(getConf());
        for (String fileName : argv) {
            FileStatus[] fileStatuses = fs.globStatus(new Path(fileName));
            for (FileStatus fileStatus : fileStatuses) {
                if (!fileStatus.isDir()) {
                    out.println("FILE: " + fileStatus.getPath().toString());

                    String path = fileStatus.getPath().toUri().getPath();
                    LocatedBlocks blocks = namenode.getBlockLocations(path, 0, fileStatus.getLen());

                    for (LocatedBlock block : blocks.getLocatedBlocks()) {
                        b.setLength(0);
                        b.append(block.getBlock());
                        b.append(" - ");

                        List<String> nodes = newArrayList();
                        for (DatanodeInfo datanodeInfo : block.getLocations()) {
                            nodes.add(datanodeInfo.name);
                        }
                        b.append(Joiner.on(", ").join(nodes));
                        out.println(b.toString());
                    }

                }
                out.println();
            }
        }
        return 0;
    }

    @Override
    public String getName() {
        return "blockFinder";
    }

    @Override
    public String getDescription() {
        return getShortDescription();
    }

    @Override
    public String getShortDescription() {
        return "Display the block names and locations of the files specified";
    }

}