/*
* $Header: /home/cvs/jakarta-commons/httpclient/src/java/org/apache/commons/httpclient/ChunkedOutputStream.java,v 1.10 2003/04/19 22:29:31 mbecke Exp $
* $Revision: 1.10 $
* $Date: 2003/04/19 22:29:31 $
*
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2002-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* .
*
* [Additional notices, if required by prior licensing conditions]
*
*/
package org.apache.commons.httpclient;
import java.io.IOException;
import java.io.OutputStream;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
*
* Wrapper supporting the chunked transfer encoding.
*
*
* @author Remy Maucherat
* @author Sean C. Sullivan
* @author dIon Gillard
* @author Oleg Kalnichevski
* @author Mike Bowler
* @version $Revision: 1.10 $ $Date: 2003/04/19 22:29:31 $
*
* @see ChunkedInputStream
* @since 2.0
*
*/
public class ChunkedOutputStream extends OutputStream {
// ------------------------------------------------------- Static Variables
/** "\r\n", as bytes. */
private static final byte CRLF[] = new byte[] {(byte) 13, (byte) 10};
/** End chunk */
private static final byte ENDCHUNK[] = CRLF;
/** 0 */
private static final byte ZERO[] = new byte[] {(byte) '0'};
/** 1 */
private static final byte ONE[] = new byte[] {(byte) '1'};
/** Log object for this class. */
private static final Log LOG = LogFactory.getLog(ChunkedOutputStream.class);
// ----------------------------------------------------- Instance Variables
/** Has this stream been closed? */
private boolean closed = false;
/** The underlying output stream to which we will write data */
private OutputStream stream = null;
// ----------------------------------------------------------- Constructors
/**
* Construct an output stream wrapping the given stream.
* The stream will not use chunking.
*
* @param stream wrapped output stream. Must be non-null.
*/
public ChunkedOutputStream(OutputStream stream) {
if (stream == null) {
throw new NullPointerException("stream parameter is null");
}
this.stream = stream;
}
// --------------------------------------------------------- Public Methods
/**
* Writes a String to the client, without a carriage return
* line feed (CRLF) character at the end. The platform default encoding is
* used!
*
* @param s the String to send to the client. Must be non-null.
* @throws IOException if an input or output exception occurred
*/
public void print(String s) throws IOException {
LOG.trace("enter ChunckedOutputStream.print(String)");
if (s == null) {
s = "null";
}
write(HttpConstants.getBytes(s));
}
/**
* Writes a carriage return-line feed (CRLF) to the client.
*
* @throws IOException if an input or output exception occurred
*/
public void println() throws IOException {
print("\r\n");
}
/**
* Writes a String to the client,
* followed by a carriage return-line feed (CRLF).
*
* @param s the String to write to the client
* @exception IOException if an input or output exception occurred
*/
public void println(String s) throws IOException {
print(s);
println();
}
// -------------------------------------------- OutputStream Methods
/**
* Write the specified byte to our output stream.
*
* @param b The byte to be written
* @throws IOException if an input/output error occurs
* @throws IllegalStateException if stream already closed
*/
public void write (int b) throws IOException, IllegalStateException {
if (closed) {
throw new IllegalStateException("Output stream already closed");
}
//FIXME: If using chunking, the chunks are ONE byte long!
stream.write(ONE, 0, ONE.length);
stream.write(CRLF, 0, CRLF.length);
stream.write(b);
stream.write(ENDCHUNK, 0, ENDCHUNK.length);
LOG.debug("Writing chunk (length: 1)");
}
/**
* Write the specified byte array.
*
* @param b the byte array to write out
* @param off the offset within b to start writing from
* @param len the length of data within b to write
* @throws IOException when errors occur writing output
*/
public void write (byte[] b, int off, int len) throws IOException {
LOG.trace("enter ChunckedOutputStream.write(byte[], int, int)");
if (closed) {
throw new IllegalStateException("Output stream already closed");
}
byte chunkHeader[] = HttpConstants.getBytes (
Integer.toHexString(len) + "\r\n");
stream.write(chunkHeader, 0, chunkHeader.length);
stream.write(b, off, len);
stream.write(ENDCHUNK, 0, ENDCHUNK.length);
if (LOG.isDebugEnabled()) {
LOG.debug("Writing chunk (length: " + len + ")");
}
}
/**
* Close this output stream, causing any buffered data to be flushed and
* any further output data to throw an IOException. The underlying stream
* is not closed!
*
* @throws IOException if an error occurs closing the stream
*/
public void writeClosingChunk() throws IOException {
LOG.trace("enter ChunkedOutputStream.writeClosingChunk()");
if (!closed) {
try {
// Write the final chunk.
stream.write(ZERO, 0, ZERO.length);
stream.write(CRLF, 0, CRLF.length);
stream.write(ENDCHUNK, 0, ENDCHUNK.length);
LOG.debug("Writing closing chunk");
} catch (IOException e) {
LOG.debug("Unexpected exception caught when closing "
+ "output stream", e);
throw e;
} finally {
// regardless of what happens, mark the stream as closed.
// if there are errors closing it, there's not much we can do
// about it
closed = true;
}
}
}
/**
* Flushes the underlying stream.
* @throws IOException If an IO problem occurs.
*/
public void flush() throws IOException {
stream.flush();
}
/**
* Close this output stream, causing any buffered data to be flushed and
* any further output data to throw an IOException. The underlying stream
* is not closed!
*
* @throws IOException if an error occurs closing the stream
*/
public void close() throws IOException {
LOG.trace("enter ChunkedOutputStream.close()");
writeClosingChunk();
super.close();
}
}
