cn.lhfei.hadoop.ch04.FileDecompressor.java Source code

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Here is the source code for cn.lhfei.hadoop.ch04.FileDecompressor.java

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/*
 * Copyright 2010-2011 the original author or authors.
 *
 * 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 cn.lhfei.hadoop.ch04;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URI;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.IOUtils;
import org.apache.hadoop.io.compress.CompressionCodec;
import org.apache.hadoop.io.compress.CompressionCodecFactory;

/**
 * @version 0.1
 *
 * @author Hefei Li
 *
 * @since Oct 27, 2014
 */

public class FileDecompressor {

    /**
     * use case: % hadoop FileDecompressor file.gz
     * @param args
     */
    public static void main(String[] args) {
        FileSystem fs = null;
        String uri = args[0];
        Path inputPath = null;
        Configuration conf = new Configuration();
        CompressionCodecFactory factory = null;

        InputStream in = null;
        OutputStream out = null;

        try {
            fs = FileSystem.get(URI.create(uri), conf);
            inputPath = new Path(uri);
            factory = new CompressionCodecFactory(conf);
            CompressionCodec codec = factory.getCodec(inputPath);
            if (codec == null) {
                System.err.println("No codec found for " + uri);
                System.exit(1);
            }

            String outputUri = CompressionCodecFactory.removeSuffix(uri, codec.getDefaultExtension());

            in = codec.createInputStream(fs.open(inputPath));
            out = fs.create(new Path(outputUri));

            IOUtils.copyBytes(in, out, conf);

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            IOUtils.closeStream(in);
            IOUtils.closeStream(out);
        }
    }

}