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Small utility lib to speed up Avro write

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package com.landoop.avro.codec;

import org.apache.avro.file.Codec;
import org.apache.avro.file.DataFileConstants;
import org.xerial.snappy.Snappy;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.zip.CRC32;

/**
 * Implements Snappy compression and decompression.
 */
class SnappyCodec extends Codec {
    private CRC32 crc32 = new CRC32();

    @Override
    public String getName() {
        return DataFileConstants.SNAPPY_CODEC;
    }

    @Override
    public ByteBuffer compress(ByteBuffer in) throws IOException {
        ByteBuffer out = ByteBuffer.allocate(Snappy.maxCompressedLength(in.remaining()) + 4);
        int size = Snappy.compress(in.array(), in.position(), in.remaining(),
                out.array(), 0);
        crc32.reset();
        crc32.update(in.array(), in.position(), in.remaining());
        out.putInt(size, (int) crc32.getValue());

        out.limit(size + 4);

        return out;
    }

    @Override
    public ByteBuffer decompress(ByteBuffer in) throws IOException {
        ByteBuffer out = ByteBuffer.allocate
                (Snappy.uncompressedLength(in.array(), in.position(), in.remaining() - 4));
        int size = Snappy.uncompress(in.array(), in.position(), in.remaining() - 4,
                out.array(), 0);
        out.limit(size);

        crc32.reset();
        crc32.update(out.array(), 0, size);
        if (in.getInt(in.limit() - 4) != (int) crc32.getValue())
            throw new IOException("Checksum failure");

        return out;
    }

    @Override
    public int hashCode() {
        return getName().hashCode();
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null || obj.getClass() != getClass())
            return false;
        return true;
    }

}