| /* |
| * |
| * 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 java.nio.ByteBuffer; |
| |
| import org.apache.qpid.proton.engine.Transport; |
| import org.apache.qpid.proton.engine.TransportException; |
| import org.apache.qpid.proton.engine.impl.TransportWrapper; |
| |
| public abstract class HandshakeSniffingTransportWrapper<T1 extends TransportWrapper, T2 extends TransportWrapper> |
| implements TransportWrapper |
| { |
| |
| protected final T1 _wrapper1; |
| protected final T2 _wrapper2; |
| |
| private boolean _tail_closed = false; |
| private boolean _head_closed = false; |
| protected TransportWrapper _selectedTransportWrapper; |
| |
| private final ByteBuffer _determinationBuffer; |
| |
| protected HandshakeSniffingTransportWrapper |
| (T1 wrapper1, |
| T2 wrapper2) |
| { |
| _wrapper1 = wrapper1; |
| _wrapper2 = wrapper2; |
| _determinationBuffer = ByteBuffer.allocate(bufferSize()); |
| } |
| |
| @Override |
| public int capacity() |
| { |
| if (isDeterminationMade()) |
| { |
| return _selectedTransportWrapper.capacity(); |
| } |
| else |
| { |
| if (_tail_closed) { return Transport.END_OF_STREAM; } |
| return _determinationBuffer.remaining(); |
| } |
| } |
| |
| @Override |
| public int position() |
| { |
| if (isDeterminationMade()) |
| { |
| return _selectedTransportWrapper.position(); |
| } |
| else |
| { |
| if (_tail_closed) { return Transport.END_OF_STREAM; } |
| return _determinationBuffer.position(); |
| } |
| } |
| |
| @Override |
| public ByteBuffer tail() |
| { |
| if (isDeterminationMade()) |
| { |
| return _selectedTransportWrapper.tail(); |
| } |
| else |
| { |
| return _determinationBuffer; |
| } |
| } |
| |
| protected abstract int bufferSize(); |
| |
| protected abstract void makeDetermination(byte[] bytes); |
| |
| @Override |
| public void process() throws TransportException |
| { |
| if (isDeterminationMade()) |
| { |
| _selectedTransportWrapper.process(); |
| } |
| else if (_determinationBuffer.remaining() == 0) |
| { |
| _determinationBuffer.flip(); |
| byte[] bytesInput = new byte[_determinationBuffer.remaining()]; |
| _determinationBuffer.get(bytesInput); |
| makeDetermination(bytesInput); |
| _determinationBuffer.rewind(); |
| |
| // TODO what if the selected transport has insufficient capacity?? Maybe use pour, and then try to finish pouring next time round. |
| _selectedTransportWrapper.tail().put(_determinationBuffer); |
| _selectedTransportWrapper.process(); |
| } else if (_tail_closed) { |
| throw new TransportException("connection aborted"); |
| } |
| } |
| |
| @Override |
| public void close_tail() |
| { |
| try { |
| if (isDeterminationMade()) |
| { |
| _selectedTransportWrapper.close_tail(); |
| } |
| } finally { |
| _tail_closed = true; |
| } |
| } |
| |
| @Override |
| public int pending() |
| { |
| if (_head_closed) { return Transport.END_OF_STREAM; } |
| |
| if (isDeterminationMade()) { |
| return _selectedTransportWrapper.pending(); |
| } else { |
| return 0; |
| } |
| |
| } |
| |
| private static final ByteBuffer EMPTY = ByteBuffer.allocate(0); |
| |
| @Override |
| public ByteBuffer head() |
| { |
| if (isDeterminationMade()) { |
| return _selectedTransportWrapper.head(); |
| } else { |
| return EMPTY; |
| } |
| } |
| |
| @Override |
| public void pop(int bytes) |
| { |
| if (isDeterminationMade()) { |
| _selectedTransportWrapper.pop(bytes); |
| } else if (bytes > 0) { |
| throw new IllegalStateException("no bytes have been read"); |
| } |
| } |
| |
| @Override |
| public void close_head() |
| { |
| if (isDeterminationMade()) { |
| _selectedTransportWrapper.close_head(); |
| } else { |
| _head_closed = true; |
| } |
| } |
| |
| protected boolean isDeterminationMade() |
| { |
| return _selectedTransportWrapper != null; |
| } |
| |
| } |