org.eclipse.jetty.http.gzip.GzipStream Maven / Gradle / Ivy
// ========================================================================
// Copyright (c) Webtide LLC
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
// You may elect to redistribute this code under either of these licenses.
// ========================================================================
package org.eclipse.jetty.http.gzip;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.util.zip.GZIPOutputStream;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.eclipse.jetty.util.ByteArrayOutputStream2;
/* ------------------------------------------------------------ */
/**
*/
public class GzipStream extends ServletOutputStream
{
protected HttpServletRequest _request;
protected HttpServletResponse _response;
protected OutputStream _out;
protected ByteArrayOutputStream2 _bOut;
protected GZIPOutputStream _gzOut;
protected boolean _closed;
protected int _bufferSize;
protected int _minGzipSize;
protected long _contentLength;
protected boolean _doNotGzip;
/**
* Instantiates a new gzip stream.
*
* @param request the request
* @param response the response
* @param contentLength the content length
* @param bufferSize the buffer size
* @param minGzipSize the min gzip size
* @throws IOException Signals that an I/O exception has occurred.
*/
public GzipStream(HttpServletRequest request,HttpServletResponse response,long contentLength,int bufferSize, int minGzipSize) throws IOException
{
_request=request;
_response=response;
_contentLength=contentLength;
_bufferSize=bufferSize;
_minGzipSize=minGzipSize;
if (minGzipSize==0)
doGzip();
}
/**
* Reset buffer.
*/
public void resetBuffer()
{
if (_response.isCommitted())
throw new IllegalStateException("Committed");
_closed=false;
_out=null;
_bOut=null;
if (_gzOut!=null)
_response.setHeader("Content-Encoding",null);
_gzOut=null;
_doNotGzip=false;
}
/**
* Sets the content length.
*
* @param length the new content length
*/
public void setContentLength(long length)
{
_contentLength=length;
if (_doNotGzip && length>=0)
{
if(_contentLength0 && _contentLength<_minGzipSize)
doNotGzip();
else
doGzip();
}
_out.flush();
}
/* ------------------------------------------------------------ */
/**
* @see java.io.OutputStream#close()
*/
public void close() throws IOException
{
if (_closed)
return;
if (_request.getAttribute("javax.servlet.include.request_uri")!=null)
flush();
else
{
if (_bOut!=null)
{
if (_contentLength<0)
_contentLength=_bOut.getCount();
if (_contentLength<_minGzipSize)
doNotGzip();
else
doGzip();
}
else if (_out==null)
{
doNotGzip();
}
if (_gzOut!=null)
_gzOut.close();
else
_out.close();
_closed=true;
}
}
/**
* Finish.
*
* @throws IOException Signals that an I/O exception has occurred.
*/
public void finish() throws IOException
{
if (!_closed)
{
if (_out==null || _bOut!=null)
{
if (_contentLength>0 && _contentLength<_minGzipSize)
doNotGzip();
else
doGzip();
}
if (_gzOut!=null && !_closed)
{
_closed=true;
_gzOut.close();
}
}
}
/* ------------------------------------------------------------ */
/**
* @see java.io.OutputStream#write(int)
*/
public void write(int b) throws IOException
{
checkOut(1);
_out.write(b);
}
/* ------------------------------------------------------------ */
/**
* @see java.io.OutputStream#write(byte[])
*/
public void write(byte b[]) throws IOException
{
checkOut(b.length);
_out.write(b);
}
/* ------------------------------------------------------------ */
/**
* @see java.io.OutputStream#write(byte[], int, int)
*/
public void write(byte b[], int off, int len) throws IOException
{
checkOut(len);
_out.write(b,off,len);
}
/**
* Sets the content encoding gzip.
*
* @return true, if successful
*/
protected boolean setContentEncodingGzip()
{
_response.setHeader("Content-Encoding", "gzip");
return _response.containsHeader("Content-Encoding");
}
/**
* Do gzip.
*
* @throws IOException Signals that an I/O exception has occurred.
*/
public void doGzip() throws IOException
{
if (_gzOut==null)
{
if (_response.isCommitted())
throw new IllegalStateException();
if (setContentEncodingGzip())
{
_out=_gzOut=new GZIPOutputStream(_response.getOutputStream(),_bufferSize);
if (_bOut!=null)
{
_out.write(_bOut.getBuf(),0,_bOut.getCount());
_bOut=null;
}
}
else
doNotGzip();
}
}
/**
* Do not gzip.
*
* @throws IOException Signals that an I/O exception has occurred.
*/
public void doNotGzip() throws IOException
{
if (_gzOut!=null)
throw new IllegalStateException();
if (_out==null || _bOut!=null )
{
_doNotGzip = true;
_out=_response.getOutputStream();
setContentLength(_contentLength);
if (_bOut!=null)
_out.write(_bOut.getBuf(),0,_bOut.getCount());
_bOut=null;
}
}
/**
* Check out.
*
* @param length the length
* @throws IOException Signals that an I/O exception has occurred.
*/
private void checkOut(int length) throws IOException
{
if (_closed)
throw new IOException("CLOSED");
if (_out==null)
{
if (_response.isCommitted() || (_contentLength>=0 && _contentLength<_minGzipSize))
doNotGzip();
else if (length>_minGzipSize)
doGzip();
else
_out=_bOut=new ByteArrayOutputStream2(_bufferSize);
}
else if (_bOut!=null)
{
if (_response.isCommitted() || (_contentLength>=0 && _contentLength<_minGzipSize))
doNotGzip();
else if (length>=(_bOut.getBuf().length -_bOut.getCount()))
doGzip();
}
}
/**
* Allows derived implementations to replace PrintWriter implementation.
*/
protected PrintWriter newWriter(OutputStream out,String encoding) throws UnsupportedEncodingException
{
return encoding==null?new PrintWriter(out):new PrintWriter(new OutputStreamWriter(out,encoding));
}
}