org.elasticsearch.common.compress.lzf.LZFCompressor Maven / Gradle / Ivy
/*
* Licensed to ElasticSearch and Shay Banon under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. ElasticSearch licenses this
* file to you 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.elasticsearch.common.compress.lzf;
import com.ning.compress.lzf.ChunkDecoder;
import com.ning.compress.lzf.LZFChunk;
import com.ning.compress.lzf.LZFEncoder;
import com.ning.compress.lzf.util.ChunkDecoderFactory;
import org.apache.lucene.store.IndexInput;
import org.elasticsearch.common.bytes.BytesReference;
import org.elasticsearch.common.compress.CompressedIndexInput;
import org.elasticsearch.common.compress.CompressedStreamInput;
import org.elasticsearch.common.compress.CompressedStreamOutput;
import org.elasticsearch.common.compress.Compressor;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.io.stream.StreamOutput;
import org.elasticsearch.common.logging.Loggers;
import org.elasticsearch.common.settings.Settings;
import org.jboss.netty.buffer.ChannelBuffer;
import java.io.IOException;
/**
*/
public class LZFCompressor implements Compressor {
static final byte[] LUCENE_HEADER = {'L', 'Z', 'F', 0};
public static final String TYPE = "lzf";
private ChunkDecoder decoder;
public LZFCompressor() {
this.decoder = ChunkDecoderFactory.optimalInstance();
Loggers.getLogger(LZFCompressor.class).debug("using [{}] decoder", this.decoder.getClass().getSimpleName());
}
@Override
public String type() {
return TYPE;
}
@Override
public void configure(Settings settings) {
String decoderType = settings.get("compress.lzf.decoder", null);
if (decoderType != null) {
if ("optimal".equalsIgnoreCase(decoderType)) {
this.decoder = ChunkDecoderFactory.optimalInstance();
Loggers.getLogger(LZFCompressor.class).debug("using [{}] decoder", this.decoder.getClass().getSimpleName());
} else if ("safe".equalsIgnoreCase(decoderType)) {
this.decoder = ChunkDecoderFactory.safeInstance();
Loggers.getLogger(LZFCompressor.class).debug("using [{}] decoder", this.decoder.getClass().getSimpleName());
} else {
Loggers.getLogger(LZFCompressor.class).warn("decoder type not recognized [{}], still using [{}]", decoderType, this.decoder.getClass().getSimpleName());
}
}
}
@Override
public boolean isCompressed(BytesReference bytes) {
return bytes.length() >= 3 &&
bytes.get(0) == LZFChunk.BYTE_Z &&
bytes.get(1) == LZFChunk.BYTE_V &&
(bytes.get(2) == LZFChunk.BLOCK_TYPE_COMPRESSED || bytes.get(2) == LZFChunk.BLOCK_TYPE_NON_COMPRESSED);
}
@Override
public boolean isCompressed(byte[] data, int offset, int length) {
return length >= 3 &&
data[offset] == LZFChunk.BYTE_Z &&
data[offset + 1] == LZFChunk.BYTE_V &&
(data[offset + 2] == LZFChunk.BLOCK_TYPE_COMPRESSED || data[offset + 2] == LZFChunk.BLOCK_TYPE_NON_COMPRESSED);
}
@Override
public boolean isCompressed(ChannelBuffer buffer) {
int offset = buffer.readerIndex();
return buffer.readableBytes() >= 3 &&
buffer.getByte(offset) == LZFChunk.BYTE_Z &&
buffer.getByte(offset + 1) == LZFChunk.BYTE_V &&
(buffer.getByte(offset + 2) == LZFChunk.BLOCK_TYPE_COMPRESSED || buffer.getByte(offset + 2) == LZFChunk.BLOCK_TYPE_NON_COMPRESSED);
}
@Override
public boolean isCompressed(IndexInput in) throws IOException {
long currentPointer = in.getFilePointer();
// since we have some metdata before the first compressed header, we check on our specific header
if (in.length() - currentPointer < (LUCENE_HEADER.length)) {
return false;
}
for (int i = 0; i < LUCENE_HEADER.length; i++) {
if (in.readByte() != LUCENE_HEADER[i]) {
in.seek(currentPointer);
return false;
}
}
in.seek(currentPointer);
return true;
}
@Override
public byte[] uncompress(byte[] data, int offset, int length) throws IOException {
return decoder.decode(data, offset, length);
}
@Override
public byte[] compress(byte[] data, int offset, int length) throws IOException {
return LZFEncoder.encode(data, offset, length);
}
@Override
public CompressedStreamInput streamInput(StreamInput in) throws IOException {
return new LZFCompressedStreamInput(in, decoder);
}
@Override
public CompressedStreamOutput streamOutput(StreamOutput out) throws IOException {
return new LZFCompressedStreamOutput(out);
}
@Override
public CompressedIndexInput indexInput(IndexInput in) throws IOException {
return new LZFCompressedIndexInput(in, decoder);
}
}