/*
* Copyright 2011 Jeanfrancois Arcand
*
* 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.
*/
// $Id: ZlibOutputStream.java 105 2007-08-07 07:45:45Z pornin $
/*
* Copyright (c) 2007 Thomas Pornin
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package org.atmosphere.gwt.server.deflate;
import org.atmosphere.gwt.server.deflate.Deflater;
import java.io.IOException;
import java.io.OutputStream;
/**
* <p>
* This class implements a stream which compresses data into the <code>zlib</code> format (RFC 1950).
* </p>
*
* <p>
* The compression level can be specified, as a symbolic value identical to what the <code>Deflater</code> class
* expects. The default compression level is <code>MEDIUM</code>.
* </p>
*
* @version $Revision: 105 $
* @author Thomas Pornin
*/
public class DeflaterOutputStream extends OutputStream {
private Deflater deflater;
/**
* Create the stream with the provided transport stream. The default compression level (<code>MEDIUM</code>) is
* used.
*
* @param out
* the transport stream
* @throws IOException
* on I/O error with the transport stream
*/
public DeflaterOutputStream(OutputStream out) throws IOException {
this(out, Deflater.MEDIUM);
}
/**
* Create the stream with the provided transport stream. The provided compression level is used.
*
* @param out
* the transport stream
* @param level
* the compression level
* @throws IOException
* on I/O error with the transport stream
*/
public DeflaterOutputStream(OutputStream out, int level) throws IOException {
deflater = new Deflater(level);
deflater.setOut(out);
}
/**
* Close this stream; the transport stream is also closed.
*
* @throws IOException
* on I/O error with the transport stream
*/
@Override
public void close() throws IOException {
deflater.terminate();
deflater.getOut().close();
}
/**
* Flush this stream; the transport stream is also flushed. At the DEFLATE level, a "sync flush" is performed, which
* ensures that output bytes written so far on the transport stream are sufficient to recover all the input bytes
* currently processed.
*
* @throws IOException
* on I/O error with the transport stream
*/
@Override
public void flush() throws IOException {
deflater.flushSync(true);
deflater.getOut().flush();
}
/** @see OutputStream */
@Override
public void write(int b) throws IOException {
write(new byte[] { (byte) b }, 0, 1);
}
/** @see OutputStream */
@Override
public void write(byte[] buf) throws IOException {
write(buf, 0, buf.length);
}
/** @see OutputStream */
@Override
public void write(byte[] buf, int off, int len) throws IOException {
deflater.process(buf, off, len);
}
}