| /* |
| * |
| * 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.management.messages; |
| |
| import java.io.IOException; |
| import java.nio.ByteBuffer; |
| |
| import org.apache.qpid.api.Message; |
| import org.apache.qpid.management.configuration.Configuration; |
| import org.apache.qpid.management.domain.services.SequenceNumberGenerator; |
| import org.apache.qpid.transport.DeliveryProperties; |
| import org.apache.qpid.transport.Header; |
| import org.apache.qpid.transport.MessageProperties; |
| import org.apache.qpid.transport.codec.BBEncoder; |
| |
| /** |
| * Message implementation used for specific management purposes. |
| * |
| * @author Andrea Gazzarini |
| */ |
| public abstract class ManagementMessage implements Message |
| { |
| /** |
| * Strategy interface for building / getting data. |
| * |
| * @author Andrea Gazzarini |
| */ |
| private interface IDataBuilderStrategy |
| { |
| ByteBuffer getData(); |
| }; |
| |
| /** |
| * Strategy used for retrieving raw data from this message when it has been already encoded. |
| */ |
| IDataBuilderStrategy READING = new IDataBuilderStrategy() |
| { |
| public ByteBuffer getData() { |
| return _data; |
| }; |
| }; |
| |
| /** |
| * Strategy used for retrieving raw data from this message when it hasn't been already encoded. |
| */ |
| IDataBuilderStrategy ACCUMULATING = new IDataBuilderStrategy() |
| { |
| public ByteBuffer getData() { |
| _codec.writeInt8((byte)opcode()); |
| _codec.writeSequenceNo(sequenceNumber()); |
| |
| specificMessageEncoding(); |
| |
| _data =_codec.segment(); |
| _reader = READING; |
| return _data; |
| } |
| }; |
| |
| protected BBEncoder _codec; |
| protected ByteBuffer _data; |
| private int _messageTransferId; |
| private IDataBuilderStrategy _reader = ACCUMULATING; |
| |
| /** |
| * Builds an empty management message. |
| */ |
| ManagementMessage() |
| { |
| _codec = new BBEncoder(100); |
| _codec.writeMagicNumber(); |
| } |
| |
| /** |
| * Returns the sequence number that will be used for this message. |
| * |
| * @return the sequence number that will be used for this message. |
| */ |
| protected int sequenceNumber () |
| { |
| return SequenceNumberGenerator.getNextSequenceNumber(); |
| } |
| |
| /** |
| * Returns the opcode that will be used for this message. |
| * |
| * @return the opcode that will be used for this message. |
| */ |
| abstract char opcode (); |
| |
| /** |
| * Returns the delivery properties of this message. |
| * |
| * @return the delivery properties of this message. |
| */ |
| public DeliveryProperties getDeliveryProperties () |
| { |
| return Configuration.getInstance().getCommandDeliveryProperties(); |
| } |
| |
| /** |
| * Returns the header of this message. |
| * |
| * @return the header of this message. |
| */ |
| public Header getHeader () |
| { |
| return Configuration.getInstance().getCommandMessageHeader(); |
| } |
| |
| /** |
| * Returns the messages header properties of this message. |
| * |
| * @return the message header properties of this message. |
| */ |
| public MessageProperties getMessageProperties () |
| { |
| return Configuration.getInstance().getCommandMessageProperties(); |
| } |
| |
| /** |
| * Returns the transfer Id of this message. |
| * |
| * @return the transfer Id of this message. |
| */ |
| public int getMessageTransferId () |
| { |
| return _messageTransferId; |
| } |
| |
| /** |
| * Returns the encoded data of this message. |
| * |
| * @return the encoded data of this message. |
| */ |
| public ByteBuffer readData () throws IOException |
| { |
| return _reader.getData(); |
| } |
| |
| /** |
| * Sets the header for this message. |
| * |
| * @param header the new message header. |
| */ |
| public void setHeader (Header header) |
| { |
| // N.A. at the moment. |
| } |
| |
| public void appendData (byte[] src) throws IOException |
| { |
| } |
| |
| public void appendData (ByteBuffer src) throws IOException |
| { |
| } |
| |
| public void clearData () |
| { |
| } |
| |
| public void readData (byte[] target) throws IOException |
| { |
| } |
| |
| /** |
| * Concrete subclasses (message implementations) must define here their specific data encoding. |
| */ |
| abstract void specificMessageEncoding(); |
| } |