/*
* $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/tags/4.0/module-nio/src/main/java/org/apache/http/impl/nio/reactor/SessionOutputBufferImpl.java $
* $Revision: 744539 $
* $Date: 2009-02-14 18:23:26 +0100 (Sat, 14 Feb 2009) $
*
* ====================================================================
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
* ====================================================================
*
* 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
* <http://www.apache.org/>.
*
*/
package org.apache.http.impl.nio.reactor;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.channels.ReadableByteChannel;
import java.nio.channels.WritableByteChannel;
import java.nio.charset.CharacterCodingException;
import java.nio.charset.Charset;
import java.nio.charset.CharsetEncoder;
import java.nio.charset.CoderResult;
import org.apache.http.nio.reactor.SessionOutputBuffer;
import org.apache.http.nio.util.ByteBufferAllocator;
import org.apache.http.nio.util.ExpandableBuffer;
import org.apache.http.nio.util.HeapByteBufferAllocator;
import org.apache.http.params.HttpParams;
import org.apache.http.params.HttpProtocolParams;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.CharArrayBuffer;
/**
* Default implementation of {@link SessionOutputBuffer} based on
* the {@link ExpandableBuffer} class.
*
*
* @version $Revision: 744539 $
*
* @since 4.0
*/
public class SessionOutputBufferImpl extends ExpandableBuffer implements SessionOutputBuffer {
private static final byte[] CRLF = new byte[] {HTTP.CR, HTTP.LF};
private CharBuffer charbuffer = null;
private Charset charset = null;
private CharsetEncoder charencoder = null;
public SessionOutputBufferImpl(
int buffersize,
int linebuffersize,
final ByteBufferAllocator allocator,
final HttpParams params) {
super(buffersize, allocator);
this.charbuffer = CharBuffer.allocate(linebuffersize);
this.charset = Charset.forName(HttpProtocolParams.getHttpElementCharset(params));
this.charencoder = this.charset.newEncoder();
}
public SessionOutputBufferImpl(
int buffersize,
int linebuffersize,
final HttpParams params) {
this(buffersize, linebuffersize, new HeapByteBufferAllocator(), params);
}
public void reset(final HttpParams params) {
clear();
}
public int flush(final WritableByteChannel channel) throws IOException {
if (channel == null) {
throw new IllegalArgumentException("Channel may not be null");
}
setOutputMode();
int noWritten = channel.write(this.buffer);
return noWritten;
}
public void write(final ByteBuffer src) {
if (src == null) {
return;
}
setInputMode();
int requiredCapacity = this.buffer.position() + src.remaining();
ensureCapacity(requiredCapacity);
this.buffer.put(src);
}
public void write(final ReadableByteChannel src) throws IOException {
if (src == null) {
return;
}
setInputMode();
src.read(this.buffer);
}
private void write(final byte[] b) {
if (b == null) {
return;
}
setInputMode();
int off = 0;
int len = b.length;
int requiredCapacity = this.buffer.position() + len;
ensureCapacity(requiredCapacity);
this.buffer.put(b, off, len);
}
private void writeCRLF() {
write(CRLF);
}
public void writeLine(final CharArrayBuffer linebuffer) throws CharacterCodingException {
if (linebuffer == null) {
return;
}
// Do not bother if the buffer is empty
if (linebuffer.length() > 0 ) {
setInputMode();
this.charencoder.reset();
// transfer the string in small chunks
int remaining = linebuffer.length();
int offset = 0;
while (remaining > 0) {
int l = this.charbuffer.remaining();
boolean eol = false;
if (remaining <= l) {
l = remaining;
// terminate the encoding process
eol = true;
}
this.charbuffer.put(linebuffer.buffer(), offset, l);
this.charbuffer.flip();
boolean retry = true;
while (retry) {
CoderResult result = this.charencoder.encode(this.charbuffer, this.buffer, eol);
if (result.isError()) {
result.throwException();
}
if (result.isOverflow()) {
expand();
}
retry = !result.isUnderflow();
}
this.charbuffer.compact();
offset += l;
remaining -= l;
}
// flush the encoder
boolean retry = true;
while (retry) {
CoderResult result = this.charencoder.flush(this.buffer);
if (result.isError()) {
result.throwException();
}
if (result.isOverflow()) {
expand();
}
retry = !result.isUnderflow();
}
}
writeCRLF();
}
public void writeLine(final String s) throws IOException {
if (s == null) {
return;
}
if (s.length() > 0) {
CharArrayBuffer tmp = new CharArrayBuffer(s.length());
tmp.append(s);
writeLine(tmp);
} else {
write(CRLF);
}
}
}