org.elasticsoftware.elasticactors.cassandra.serialization.CompressingSerializer.java Source code

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Here is the source code for org.elasticsoftware.elasticactors.cassandra.serialization.CompressingSerializer.java

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/*
 * Copyright 2013 - 2017 The Original 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 org.elasticsoftware.elasticactors.cassandra.serialization;

import com.google.common.io.ByteArrayDataOutput;
import com.google.common.io.ByteStreams;
import net.jpountz.lz4.LZ4Compressor;
import net.jpountz.lz4.LZ4Factory;
import org.elasticsoftware.elasticactors.serialization.Serializer;

import java.io.IOException;

/**
 * @author Joost van de Wijgerd
 */
public final class CompressingSerializer<I> implements Serializer<I, byte[]> {
    private static final LZ4Compressor lz4Compressor = LZ4Factory.fastestJavaInstance().fastCompressor();
    private static final byte[] MAGIC_HEADER = { 0x18, 0x4D, 0x22, 0x04 };
    private final Serializer<I, byte[]> delegate;
    private final int compressionThreshold;

    public CompressingSerializer(Serializer<I, byte[]> delegate) {
        this(delegate, 2048);
    }

    public CompressingSerializer(Serializer<I, byte[]> delegate, int compressionThreshold) {
        this.delegate = delegate;
        this.compressionThreshold = compressionThreshold;
    }

    @Override
    public byte[] serialize(I object) throws IOException {
        byte[] serializedObject = delegate.serialize(object);
        if (serializedObject.length > compressionThreshold) {
            byte[] compressedBytes = lz4Compressor.compress(serializedObject);
            ByteArrayDataOutput dataOutput = ByteStreams.newDataOutput(compressedBytes.length + 8);
            dataOutput.write(MAGIC_HEADER);
            dataOutput.writeInt(serializedObject.length);
            dataOutput.write(compressedBytes);
            return dataOutput.toByteArray();
        } else {
            return serializedObject;
        }
    }
}