/*
* ====================================================================
* 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.apach3.http.impl.nio.codecs;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.nio.channels.WritableByteChannel;
import org.apach3.http.annotation.NotThreadSafe;
import org.apach3.http.impl.io.HttpTransportMetricsImpl;
import org.apach3.http.nio.FileContentEncoder;
import org.apach3.http.nio.reactor.SessionOutputBuffer;
/**
* Content encoder that cuts off after a defined number of bytes. This class
* is used to send content of HTTP messages where the end of the content entity
* is determined by the value of the <code>Content-Length header</code>.
* Entities transferred using this stream can be maximum {@link Long#MAX_VALUE}
* long.
* <p>
* This decoder is optimized to transfer data directly from
* a {@link FileChannel} to the underlying I/O session's channel whenever
* possible avoiding intermediate buffering in the session buffer.
*
* @since 4.0
*/
@NotThreadSafe
public class LengthDelimitedEncoder extends AbstractContentEncoder
implements FileContentEncoder {
private final long contentLength;
private long len;
public LengthDelimitedEncoder(
final WritableByteChannel channel,
final SessionOutputBuffer buffer,
final HttpTransportMetricsImpl metrics,
long contentLength) {
super(channel, buffer, metrics);
if (contentLength < 0) {
throw new IllegalArgumentException("Content length may not be negative");
}
this.contentLength = contentLength;
this.len = 0;
}
public int write(final ByteBuffer src) throws IOException {
if (src == null) {
return 0;
}
assertNotCompleted();
int lenRemaining = (int) (this.contentLength - this.len);
int bytesWritten;
if (src.remaining() > lenRemaining) {
int oldLimit = src.limit();
int newLimit = oldLimit - (src.remaining() - lenRemaining);
src.limit(newLimit);
bytesWritten = this.channel.write(src);
src.limit(oldLimit);
} else {
bytesWritten = this.channel.write(src);
}
if (bytesWritten > 0) {
this.metrics.incrementBytesTransferred(bytesWritten);
}
this.len += bytesWritten;
if (this.len >= this.contentLength) {
this.completed = true;
}
return bytesWritten;
}
public long transfer(
final FileChannel src,
long position,
long count) throws IOException {
if (src == null) {
return 0;
}
assertNotCompleted();
int lenRemaining = (int) (this.contentLength - this.len);
long bytesWritten;
if (count > lenRemaining) {
count = lenRemaining;
}
bytesWritten = src.transferTo(position, count, this.channel);
if (bytesWritten > 0) {
this.metrics.incrementBytesTransferred(bytesWritten);
}
this.len += bytesWritten;
if (this.len >= this.contentLength) {
this.completed = true;
}
return bytesWritten;
}
@Override
public String toString() {
StringBuilder buffer = new StringBuilder();
buffer.append("[content length: ");
buffer.append(this.contentLength);
buffer.append("; pos: ");
buffer.append(this.len);
buffer.append("; completed: ");
buffer.append(this.completed);
buffer.append("]");
return buffer.toString();
}
}