/*
* ====================================================================
* 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
* Content-Length header
.
* Entities transferred using this stream can be maximum {@link Long#MAX_VALUE}
* long.
*
* This decoder is optimized to transfer data directly from the underlying * I/O session's channel to a {@link FileChannel}, whenever * possible avoiding intermediate buffering in the session buffer. * * @since 4.0 */ @NotThreadSafe public class LengthDelimitedDecoder extends AbstractContentDecoder implements FileContentDecoder { private final long contentLength; private long len; public LengthDelimitedDecoder( final ReadableByteChannel channel, final SessionInputBuffer 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; } public int read(final ByteBuffer dst) throws IOException { if (dst == null) { throw new IllegalArgumentException("Byte buffer may not be null"); } if (this.completed) { return -1; } int chunk = (int) Math.min((this.contentLength - this.len), Integer.MAX_VALUE); int bytesRead; if (this.buffer.hasData()) { int maxLen = Math.min(chunk, this.buffer.length()); bytesRead = this.buffer.read(dst, maxLen); } else { if (dst.remaining() > chunk) { int oldLimit = dst.limit(); int newLimit = oldLimit - (dst.remaining() - chunk); dst.limit(newLimit); bytesRead = this.channel.read(dst); dst.limit(oldLimit); } else { bytesRead = this.channel.read(dst); } if (bytesRead > 0) { this.metrics.incrementBytesTransferred(bytesRead); } } if (bytesRead == -1) { this.completed = true; if (this.len < this.contentLength) { throw new ConnectionClosedException( "Premature end of Content-Length delimited message body (expected: " + this.contentLength + "; received: " + this.len); } } this.len += bytesRead; if (this.len >= this.contentLength) { this.completed = true; } if (this.completed && bytesRead == 0) { return -1; } else { return bytesRead; } } public long transfer( final FileChannel dst, long position, long count) throws IOException { if (dst == null) { return 0; } if (this.completed) { return -1; } int chunk = (int) Math.min((this.contentLength - this.len), Integer.MAX_VALUE); long bytesRead; if (this.buffer.hasData()) { int maxLen = Math.min(chunk, this.buffer.length()); dst.position(position); bytesRead = this.buffer.read(dst, maxLen); } else { if (count > chunk) { count = chunk; } if (this.channel.isOpen()) { if (position > dst.size()) { throw new IOException("Position past end of file [" + position + " > " + dst.size() + "]"); } bytesRead = dst.transferFrom(this.channel, position, count); } else { bytesRead = -1; } if (bytesRead > 0) { this.metrics.incrementBytesTransferred(bytesRead); } } if (bytesRead == -1) { this.completed = true; if (this.len < this.contentLength) { throw new ConnectionClosedException( "Premature end of Content-Length delimited message body (expected: " + this.contentLength + "; received: " + this.len); } } this.len += bytesRead; if (this.len >= this.contentLength) { this.completed = true; } return bytesRead; } @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(); } }