/**
* This file is part of muCommander, http://www.mucommander.com
* Copyright (C) 2002-2016 Maxence Bernard
*
* muCommander is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* muCommander 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package com.mucommander.commons.file.archive.zip.provider;
import java.io.IOException;
import java.io.OutputStream;
import java.util.zip.Deflater;
/**
* DeflatedOutputStream compresses data using the DEFLATED compression method.
*
* <p>--------------------------------------------------------------------------------------------------------------<br>
* <br>
* This class is based off the <code>org.apache.tools.zip</code> package of the <i>Apache Ant</i> project. The Ant
* code has been modified under the terms of the Apache License which you can find in the bundled muCommander license
* file. It was forked at version 1.7.0 of Ant.</p>
*
* @author Maxence Bernard
*/
public class DeflatedOutputStream extends ZipEntryOutputStream {
/** Deflater instance that does the actual compression work */
protected Deflater deflater;
/** Buffer used to deflate data */
protected byte[] buf;
/**
* Creates a new <code>DeflatedOutputStream</code> that writes compressed data to the given <code>OutputStream</code>
* and automatically updates the supplied CRC32 checksum.
*
* @param out the OutputStream where the compressed data is sent to
* @param deflater the Deflater that compresses data, reset before first use
* @param buf the buffer used to deflate data
*/
public DeflatedOutputStream(OutputStream out, Deflater deflater, byte buf[]) {
super(out, ZipConstants.DEFLATED);
this.deflater = deflater;
this.buf = buf;
deflater.reset();
}
/**
* Writes next block of compressed data to the output stream.
*
* @throws java.io.IOException on error
*/
protected void deflate() throws IOException {
int len = deflater.deflate(buf, 0, buf.length);
if (len > 0) {
out.write(buf, 0, len);
}
}
/**
* Finishes writing the DEFLATED-compressed data.
*
* @throws IOException if an I/O occurred
*/
public void finishDeflate() throws IOException {
deflater.finish();
while (!deflater.finished()) {
deflate();
}
}
/////////////////////////////////////////
// ZipEntryOutputStream implementation //
/////////////////////////////////////////
@Override
public int getTotalIn() {
return deflater.getTotalIn();
}
@Override
public int getTotalOut() {
return deflater.getTotalOut();
}
/////////////////////////////////
// OutputStream implementation //
/////////////////////////////////
/**
* Writes the given bytes to the Zip entry.
*
* @param b the byte array to write
* @param offset the start position to write from
* @param length the number of bytes to write
* @throws java.io.IOException on error
*/
@Override
public void write(byte[] b, int offset, int length) throws IOException {
if (length > 0) {
if (!deflater.finished()) {
deflater.setInput(b, offset, length);
while (!deflater.needsInput()) {
deflate();
}
}
}
crc.update(b, offset, length);
}
/**
* Completes writing the entry <b>without</b> closing the underlying <code>OutputStream</code>.
*
* @throws IOException
*/
@Override
public void close() throws IOException {
finishDeflate();
}
}