/*
* Copyright (c) 2010-2011 Julien Ponge. All rights reserved.
*
* Portions Copyright (c) 2011 Tamas Cservenak.
*
* 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 lzma.streams;
import lzma.sdk.lzma.Encoder;
import org.cservenak.streams.CoderOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import static lzma.sdk.lzma.Encoder.EMatchFinderTypeBT2;
import static lzma.sdk.lzma.Encoder.EMatchFinderTypeBT4;
/**
* An output stream that uses LZMA compression.
*
* @author Julien Ponge
* @author Tamas Cservenak
*/
public class LzmaOutputStream
extends CoderOutputStream
{
public LzmaOutputStream(final OutputStream out, final LzmaEncoderWrapper wrapper)
throws IOException
{
super(out, wrapper);
}
public LzmaOutputStream(final OutputStream out, final Encoder lzmaEncoder)
throws IOException
{
this(out, new LzmaEncoderWrapper(lzmaEncoder));
}
/**
* A convenient builder that makes it easier to configure the LZMA encoder.
* Default values:
* <ul>
* <li>dictionnary size: max</li>
* <li>end marker mode: true</li>
* <li>match finder: BT4</li>
* <li>number of fast bytes: 0x20</li>
* </ul>
*/
public static class Builder
{
private final OutputStream out;
private int dictionnarySize = 1 << 23;
private boolean endMarkerMode = true;
private int matchFinder = EMatchFinderTypeBT4;
private int numFastBytes = 0x20;
public Builder(OutputStream out)
{
this.out = out;
}
public Builder useMaximalDictionarySize()
{
dictionnarySize = 1 << 28;
return this;
}
public Builder useMediumDictionarySize()
{
dictionnarySize = 1 << 15;
return this;
}
public Builder useMinimalDictionarySize()
{
dictionnarySize = 1;
return this;
}
public Builder useEndMarkerMode(boolean endMarkerMode)
{
this.endMarkerMode = endMarkerMode;
return this;
}
public Builder useBT4MatchFinder()
{
matchFinder = EMatchFinderTypeBT4;
return this;
}
public Builder useBT2MatchFinder()
{
matchFinder = EMatchFinderTypeBT2;
return this;
}
public Builder useMinimalFastBytes()
{
numFastBytes = 5;
return this;
}
public Builder useMediumFastBytes()
{
numFastBytes = 0x20;
return this;
}
public Builder useMaximalFastBytes()
{
numFastBytes = 273;
return this;
}
public LzmaOutputStream build() throws IOException
{
Encoder encoder = new Encoder();
encoder.setDictionarySize(dictionnarySize);
encoder.setEndMarkerMode(endMarkerMode);
encoder.setMatchFinder(matchFinder);
encoder.setNumFastBytes(numFastBytes);
return new LzmaOutputStream(out, encoder);
}
}
}