001 /**
002 *
003 * Copyright 2004 Protique Ltd
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 *
017 **/
018
019 package org.activemq.io.impl;
020 import java.io.DataInput;
021 import java.io.IOException;
022 import org.activemq.message.Packet;
023 import org.activemq.message.WireFormatInfo;
024
025 /**
026 * Reads a ConnnectionInfo object from a Stream
027 *
028 * @version $Revision: 1.1.1.1 $
029 */
030 public class WireFormatInfoReader extends AbstractPacketReader {
031
032 AbstractDefaultWireFormat wireFormat;
033
034 WireFormatInfoReader(){
035 }
036
037 WireFormatInfoReader(AbstractDefaultWireFormat format){
038 this.wireFormat = format;
039 }
040 /**
041 * Return the type of Packet
042 *
043 * @return integer representation of the type of Packet
044 */
045 public int getPacketType() {
046 return Packet.WIRE_FORMAT_INFO;
047 }
048
049 /**
050 * @return a new Packet instance
051 */
052 public Packet createPacket() {
053 return new WireFormatInfo();
054 }
055
056 /**
057 * build a Packet instance from the data input stream
058 *
059 * @param packet A Packet object
060 * @param dataIn the data input stream to build the packet from
061 * @throws IOException
062 */
063 public void buildPacket(Packet packet, DataInput dataIn) throws IOException {
064
065 // The Magic has to match.
066 for( int i=0; i < WireFormatInfo.MAGIC.length; i++ ) {
067 if( dataIn.readByte() != WireFormatInfo.MAGIC[i]) {
068 throw new IOException("Invalid WireFormatInfo packet.");
069 }
070 }
071
072 super.buildPacket(packet, dataIn);
073 WireFormatInfo info = (WireFormatInfo) packet;
074 info.setVersion(dataIn.readInt());
075 if (wireFormat != null){
076 wireFormat.setCurrentWireFormatVersion(info.getVersion());
077 }
078 }
079 }