/*
* ====================================================================
* 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
* .
*
*/
package org.apache.http.impl.nio.codecs;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.WritableByteChannel;
import org.apache.http.annotation.NotThreadSafe;
import org.apache.http.impl.io.HttpTransportMetricsImpl;
import org.apache.http.io.BufferInfo;
import org.apache.http.nio.reactor.SessionOutputBuffer;
import org.apache.http.util.CharArrayBuffer;
/**
* Implements chunked transfer coding. The content is sent in small chunks.
* Entities transferred using this decoder can be of unlimited length.
*
* @since 4.0
*/
@NotThreadSafe
public class ChunkEncoder extends AbstractContentEncoder {
private final CharArrayBuffer lineBuffer;
private final BufferInfo bufferinfo;
public ChunkEncoder(
final WritableByteChannel channel,
final SessionOutputBuffer buffer,
final HttpTransportMetricsImpl metrics) {
super(channel, buffer, metrics);
this.lineBuffer = new CharArrayBuffer(16);
if (buffer instanceof BufferInfo) {
this.bufferinfo = (BufferInfo) buffer;
} else {
this.bufferinfo = null;
}
}
public int write(final ByteBuffer src) throws IOException {
if (src == null) {
return 0;
}
assertNotCompleted();
int chunk = src.remaining();
if (chunk == 0) {
return 0;
}
long bytesWritten = this.buffer.flush(this.channel);
if (bytesWritten > 0) {
this.metrics.incrementBytesTransferred(bytesWritten);
}
int avail;
if (this.bufferinfo != null) {
avail = this.bufferinfo.available();
} else {
avail = 4096;
}
// subtract the length of the longest chunk header
// 12345678\r\n
// \r\n
avail -= 12;
if (avail <= 0) {
return 0;
} else if (avail < chunk) {
// write no more than 'avail' bytes
chunk = avail;
this.lineBuffer.clear();
this.lineBuffer.append(Integer.toHexString(chunk));
this.buffer.writeLine(this.lineBuffer);
int oldlimit = src.limit();
src.limit(src.position() + chunk);
this.buffer.write(src);
src.limit(oldlimit);
} else {
// write all
this.lineBuffer.clear();
this.lineBuffer.append(Integer.toHexString(chunk));
this.buffer.writeLine(this.lineBuffer);
this.buffer.write(src);
}
this.lineBuffer.clear();
this.buffer.writeLine(this.lineBuffer);
return chunk;
}
@Override
public void complete() throws IOException {
assertNotCompleted();
this.lineBuffer.clear();
this.lineBuffer.append("0");
this.buffer.writeLine(this.lineBuffer);
this.lineBuffer.clear();
this.buffer.writeLine(this.lineBuffer);
this.completed = true; // == super.complete()
}
@Override
public String toString() {
StringBuilder buffer = new StringBuilder();
buffer.append("[chunk-coded; completed: ");
buffer.append(this.completed);
buffer.append("]");
return buffer.toString();
}
}