cascading.tuple.hadoop.BytesSerialization.java Source code

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Here is the source code for cascading.tuple.hadoop.BytesSerialization.java

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/*
 * Copyright (c) 2007-2010 Concurrent, Inc. All Rights Reserved.
 *
 * Project and contact information: http://www.cascading.org/
 *
 * This file is part of the Cascading project.
 *
 * Cascading is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Cascading is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Cascading.  If not, see <http://www.gnu.org/licenses/>.
 */

package cascading.tuple.hadoop;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Comparator;

import cascading.tuple.Comparison;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.io.serializer.Deserializer;
import org.apache.hadoop.io.serializer.Serialization;
import org.apache.hadoop.io.serializer.Serializer;

/**
 * Class BytesSerialization is an implementation of Hadoop's {@link Serialization} interface for use
 * by {@code byte} arrays ({@code byte[]}).
 * <p/>
 * To use, call<br/>
 * {@code TupleSerialization.addSerialization(properties,BytesSerialization.class.getName() );}
 * <p/>
 * This class also implements {@link Comparison} so it is not required to set a {@link BytesComparator}
 * when attempting to group on a byte array via GroupBy or CoGroup.
 *
 * @see cascading.tuple.hadoop.BytesComparator
 * @see Comparison
 */
@SerializationToken(tokens = { 126 }, classNames = { "[B" })
public class BytesSerialization extends Configured implements Comparison<byte[]>, Serialization<byte[]> {

    public static class RawBytesDeserializer implements Deserializer<byte[]> {
        private DataInputStream in;

        @Override
        public void open(InputStream in) throws IOException {
            if (in instanceof DataInputStream)
                this.in = (DataInputStream) in;
            else
                this.in = new DataInputStream(in);
        }

        @Override
        public byte[] deserialize(byte[] testText) throws IOException {
            int len = in.readInt();

            byte[] bytes = new byte[len];

            in.readFully(bytes);

            return bytes;
        }

        @Override
        public void close() throws IOException {
            in.close();
        }
    }

    public static class RawBytesSerializer implements Serializer<byte[]> {
        private DataOutputStream out;

        @Override
        public void open(OutputStream out) throws IOException {
            if (out instanceof DataOutputStream)
                this.out = (DataOutputStream) out;
            else
                this.out = new DataOutputStream(out);
        }

        @Override
        public void serialize(byte[] bytes) throws IOException {
            out.writeInt(bytes.length);
            out.write(bytes);
        }

        @Override
        public void close() throws IOException {
            out.close();
        }
    }

    public BytesSerialization() {
    }

    @Override
    public boolean accept(Class<?> c) {
        return byte[].class == c;
    }

    @Override
    public Serializer<byte[]> getSerializer(Class<byte[]> c) {
        return new RawBytesSerializer();
    }

    @Override
    public Deserializer<byte[]> getDeserializer(Class<byte[]> c) {
        return new RawBytesDeserializer();
    }

    @Override
    public Comparator<byte[]> getComparator(Class<byte[]> type) {
        return new BytesComparator();
    }
}