mapreduce.ZipFileRecordReader.java Source code

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Here is the source code for mapreduce.ZipFileRecordReader.java

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/**
 * Copyright 2011 Michael Cutler <m@cotdp.com>
 *
 * 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 mapreduce;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.BytesWritable;
import org.apache.hadoop.io.Text;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
import org.apache.hadoop.mapreduce.lib.input.FileSplit;

public class ZipFileRecordReader extends RecordReader<Text, BytesWritable> {
    private FSDataInputStream fsin;
    private ZipInputStream zip;
    private Text currentKey;
    private BytesWritable currentValue;
    private boolean isFinished = false;

    @Override
    public void initialize(InputSplit inputSplit, TaskAttemptContext taskAttemptContext)
            throws IOException, InterruptedException {
        FileSplit split = (FileSplit) inputSplit;
        Configuration conf = taskAttemptContext.getConfiguration();
        Path path = split.getPath();
        FileSystem fs = path.getFileSystem(conf);
        fsin = fs.open(path);
        zip = new ZipInputStream(fsin);
    }

    @Override
    public boolean nextKeyValue() throws IOException, InterruptedException {
        ZipEntry entry = zip.getNextEntry();

        if (entry == null) {
            isFinished = true;
            return false;
        }

        String strentry = entry.getName();

        for (; !strentry.endsWith(".txt");) {

            entry = zip.getNextEntry();

            if (entry == null) {
                isFinished = true;
                return false;
            }
            strentry = entry.getName();
        }

        currentKey = new Text(entry.getName());
        System.out.print(entry.getName());

        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        byte[] temp = new byte[8192];
        while (true) {
            int bytesRead = zip.read(temp, 0, 8192);
            if (bytesRead > 0)
                bos.write(temp, 0, bytesRead);
            else
                break;
        }
        zip.closeEntry();
        currentValue = new BytesWritable(bos.toByteArray());
        return true;
    }

    @Override
    public float getProgress() throws IOException, InterruptedException {
        return isFinished ? 1 : 0;
    }

    @Override
    public Text getCurrentKey() throws IOException, InterruptedException {
        return currentKey;
    }

    @Override
    public BytesWritable getCurrentValue() throws IOException, InterruptedException {
        return currentValue;
    }

    @Override
    public void close() throws IOException {
        try {
            zip.close();
        } catch (Exception e) {
        }
        try {
            fsin.close();
        } catch (Exception e) {
        }
    }
}