| /* |
| * 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. |
| */ |
| package org.apache.qpid.proton.engine.impl; |
| |
| import static org.apache.qpid.proton.engine.impl.ByteBufferUtils.*; |
| |
| import java.nio.ByteBuffer; |
| |
| import org.apache.qpid.proton.engine.Transport; |
| |
| class TransportOutputAdaptor implements TransportOutput |
| { |
| private static final ByteBuffer _emptyHead = newReadableBuffer(0).asReadOnlyBuffer(); |
| |
| private final TransportOutputWriter _transportOutputWriter; |
| private final int _maxFrameSize; |
| |
| private ByteBuffer _outputBuffer = null; |
| private ByteBuffer _head = null; |
| private boolean _output_done = false; |
| private boolean _head_closed = false; |
| private boolean _readOnlyHead = true; |
| |
| TransportOutputAdaptor(TransportOutputWriter transportOutputWriter, int maxFrameSize, boolean readOnlyHead) |
| { |
| _transportOutputWriter = transportOutputWriter; |
| _maxFrameSize = maxFrameSize > 0 ? maxFrameSize : 4*1024; |
| _readOnlyHead = readOnlyHead; |
| } |
| |
| @Override |
| public int pending() |
| { |
| if (_head_closed) { |
| return Transport.END_OF_STREAM; |
| } |
| |
| if(_outputBuffer == null) |
| { |
| init_buffers(); |
| } |
| |
| _output_done = _transportOutputWriter.writeInto(_outputBuffer); |
| _head.limit(_outputBuffer.position()); |
| |
| if (_outputBuffer.position() == 0 && _outputBuffer.capacity() > TransportImpl.BUFFER_RELEASE_THRESHOLD) |
| { |
| release_buffers(); |
| } |
| |
| if (_output_done && (_outputBuffer == null || _outputBuffer.position() == 0)) |
| { |
| return Transport.END_OF_STREAM; |
| } |
| else |
| { |
| return _outputBuffer == null ? 0 : _outputBuffer.position(); |
| } |
| } |
| |
| @Override |
| public ByteBuffer head() |
| { |
| pending(); |
| return _head != null ? _head : _emptyHead; |
| } |
| |
| @Override |
| public void pop(int bytes) |
| { |
| if (_outputBuffer != null) { |
| _outputBuffer.flip(); |
| _outputBuffer.position(bytes); |
| _outputBuffer.compact(); |
| _head.position(0); |
| _head.limit(_outputBuffer.position()); |
| if (_outputBuffer.position() == 0 && _outputBuffer.capacity() > TransportImpl.BUFFER_RELEASE_THRESHOLD) { |
| release_buffers(); |
| } |
| } |
| } |
| |
| @Override |
| public void close_head() |
| { |
| _head_closed = true; |
| _transportOutputWriter.closed(null); |
| release_buffers(); |
| } |
| |
| private void init_buffers() { |
| _outputBuffer = newWriteableBuffer(_maxFrameSize); |
| if (_readOnlyHead) { |
| _head = _outputBuffer.asReadOnlyBuffer(); |
| } else { |
| _head = _outputBuffer.duplicate(); |
| } |
| _head.limit(0); |
| } |
| |
| private void release_buffers() { |
| _head = null; |
| _outputBuffer = null; |
| } |
| } |