com.datasalt.utils.commons.io.DumpTextFileAsSequenceFile.java Source code

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Here is the source code for com.datasalt.utils.commons.io.DumpTextFileAsSequenceFile.java

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/**
 * Copyright [2011] [Datasalt Systems S.L.]
 *
 * 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 com.datasalt.utils.commons.io;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.SequenceFile;
import org.apache.hadoop.io.Text;

/**
 * This utility can be used to dump a tabulated key -> value text file as a sequencefile of [Text, Text]
 * <p>
 * Input will be fetched locally. Output will be written locally or in the remote DFS depending on your 
 * Hadoop configuration.
 * 
 * @author pere
 *
 */
public class DumpTextFileAsSequenceFile {

    public static void dump(String input, String output) throws IOException {
        Configuration conf = new Configuration();
        FileSystem fS = FileSystem.get(conf);

        BufferedReader reader = new BufferedReader(new FileReader(new File(input)));
        String line = "";
        Text t1 = new Text();
        Text t2 = new Text();

        SequenceFile.Writer writer = new SequenceFile.Writer(fS, conf, new Path(output), Text.class, Text.class);

        while ((line = reader.readLine()) != null) {
            String[] fields = line.split("\t");
            t1.set(fields[0]);
            t2.set(fields[1]);
            writer.append(t1, t2);
        }
        writer.close();
        reader.close();
    }

    public final static void main(String[] args) throws IOException {
        if (args.length != 2) {
            throw new IllegalArgumentException("Number of args shoul be 2: [input] [output]"
                    + "\n\nInput will be fetched locally. Output will be written locally or in the remote"
                    + " DFS depending on your Hadoop configuration.");
        }
        dump(args[0], args[1]);
    }
}