/*
* Syncany, www.syncany.org
* Copyright (C) 2011-2015 Philipp C. Heckel <philipp.heckel@gmail.com>
*
* This program 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.
*
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.syncany.chunk;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Map;
import java.util.zip.Deflater;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
/**
* Implements a {@link Transformer} that transforms the input/output stream
* using the Gzip compression algorithm.
*
* @author Philipp C. Heckel <philipp.heckel@gmail.com>
*/
public class GzipTransformer extends Transformer {
public static final String TYPE = "gzip";
private int level;
public GzipTransformer() {
this(Deflater.DEFAULT_COMPRESSION, null);
}
public GzipTransformer(Transformer nextTransformer) {
this(Deflater.DEFAULT_COMPRESSION, nextTransformer);
}
public GzipTransformer(int level, Transformer nextTransformer) {
super(nextTransformer);
this.level = level;
}
@Override
public void init(Map<String, String> settings) throws Exception {
// Nothing here
}
@Override
public OutputStream createOutputStream(OutputStream out) throws IOException {
if (nextTransformer == null) {
return new GZIPOutputStreamEx(out, level);
}
else {
return new GZIPOutputStreamEx(nextTransformer.createOutputStream(out), level);
}
}
@Override
public InputStream createInputStream(InputStream in) throws IOException {
if (nextTransformer == null) {
return new GZIPInputStream(in);
}
else {
return new GZIPInputStream(nextTransformer.createInputStream(in));
}
}
public static class GZIPOutputStreamEx extends GZIPOutputStream {
/**
* Level is 1-9 -- 1 being best speed, and 9 being best compression
*/
public GZIPOutputStreamEx(OutputStream out, int level) throws IOException {
super(out);
def.setLevel(level);
}
}
@Override
public String toString() {
return (nextTransformer == null) ? "Gzip" : "Gzip-"+nextTransformer;
}
}