JRMSTransportChannel xref

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    1   /***
    2    *
    3    * Copyright 2004 Protique Ltd
    4    *
    5    * Licensed under the Apache License, Version 2.0 (the "License");
    6    * you may not use this file except in compliance with the License.
    7    * You may obtain a copy of the License at
    8    *
    9    * http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   *
    17   **/
    18  package org.codehaus.activemq.transport.jrms;
    19
    20  import EDU.oswego.cs.dl.util.concurrent.SynchronizedBoolean;
    21  import com.sun.multicast.reliable.RMException;
    22  import com.sun.multicast.reliable.transport.RMPacketSocket;
    23  import com.sun.multicast.reliable.transport.SessionDoneException;
    24  import com.sun.multicast.reliable.transport.TransportProfile;
    25  import com.sun.multicast.reliable.transport.lrmp.LRMPTransportProfile;
    26  import org.apache.commons.logging.Log;
    27  import org.apache.commons.logging.LogFactory;
    28  import org.codehaus.activemq.message.Packet;
    29  import org.codehaus.activemq.message.WireFormat;
    30  import org.codehaus.activemq.transport.TransportChannelSupport;
    31  import org.codehaus.activemq.util.IdGenerator;
    32
    33  import javax.jms.JMSException;
    34  import java.io.IOException;
    35  import java.net.DatagramPacket;
    36  import java.net.InetAddress;
    37  import java.net.URI;
    38
    39  /***
    40   * A JRMS implementation of a TransportChannel
    41   *
    42   * @version $Revision: 1.20 $
    43   */
    44  public class JRMSTransportChannel extends TransportChannelSupport implements Runnable {
    45
    46      private static final int SOCKET_BUFFER_SIZE = 32 * 1024;
    47      private static final Log log = LogFactory.getLog(JRMSTransportChannel.class);
    48
    49      private WireFormat wireFormat;
    50      private SynchronizedBoolean closed;
    51      private SynchronizedBoolean started;
    52      private Thread thread; //need to change this - and use a thread pool
    53      // need to see our own messages
    54      private RMPacketSocket socket;
    55      private IdGenerator idGenerator;
    56      private String channelId;
    57      private int port;
    58      private InetAddress inetAddress;
    59      private Object lock;
    60
    61      /***
    62       * Construct basic helpers
    63       */
    64      protected JRMSTransportChannel(WireFormat wireFormat) {
    65          this.wireFormat = wireFormat;
    66          idGenerator = new IdGenerator();
    67          channelId = idGenerator.generateId();
    68          closed = new SynchronizedBoolean(false);
    69          started = new SynchronizedBoolean(false);
    70          lock = new Object();
    71      }
    72
    73      /***
    74       * Connect to a remote Node - e.g. a Broker
    75       *
    76       * @param remoteLocation
    77       * @throws JMSException
    78       */
    79      public JRMSTransportChannel(WireFormat wireFormat, URI remoteLocation) throws JMSException {
    80          this(wireFormat);
    81          try {
    82              this.port = remoteLocation.getPort();
    83              this.inetAddress = InetAddress.getByName(remoteLocation.getHost());
    84              LRMPTransportProfile profile = new LRMPTransportProfile(inetAddress, port);
    85              profile.setTTL((byte) 1);
    86              profile.setOrdered(true);
    87              this.socket = profile.createRMPacketSocket(TransportProfile.SEND_RECEIVE);
    88          }
    89          catch (Exception ioe) {
    90              ioe.printStackTrace();
    91              JMSException jmsEx = new JMSException("Initialization of JRMSTransportChannel failed: " + ioe);
    92              jmsEx.setLinkedException(ioe);
    93              throw jmsEx;
    94          }
    95      }
    96
    97      /***
    98       * close the channel
    99       */
    100     public void stop() {
    101         if (closed.commit(false, true)) {
    102             super.stop();
    103             try {
    104                 socket.close();
    105             }
    106             catch (Exception e) {
    107                 log.trace(toString() + " now closed");
    108             }
    109         }
    110     }
    111
    112     /***
    113      * start listeneing for events
    114      *
    115      * @throws JMSException if an error occurs
    116      */
    117     public void start() throws JMSException {
    118         if (started.commit(false, true)) {
    119             thread = new Thread(this, toString());
    120             if (isServerSide()) {
    121                 thread.setDaemon(true);
    122             }
    123             thread.start();
    124         }
    125     }
    126
    127     /***
    128      * Asynchronously send a Packet
    129      *
    130      * @param packet
    131      * @throws JMSException
    132      */
    133     public void asyncSend(Packet packet) throws JMSException {
    134         try {
    135             DatagramPacket dpacket = createDatagramPacket(packet);
    136
    137             // lets sync to avoid concurrent writes
    138             //synchronized (lock) {
    139             socket.send(dpacket);
    140             //}
    141         }
    142         catch (RMException rme) {
    143             JMSException jmsEx = new JMSException("syncSend failed " + rme.getMessage());
    144             jmsEx.setLinkedException(rme);
    145             throw jmsEx;
    146         }
    147         catch (IOException e) {
    148             JMSException jmsEx = new JMSException("asyncSend failed " + e.getMessage());
    149             jmsEx.setLinkedException(e);
    150             throw jmsEx;
    151         }
    152     }
    153
    154
    155     public boolean isMulticast() {
    156         return true;
    157     }
    158
    159     /***
    160      * reads packets from a Socket
    161      */
    162     public void run() {
    163         try {
    164             while (!closed.get()) {
    165                 DatagramPacket dpacket = socket.receive();
    166                 Packet packet = wireFormat.readPacket(channelId, dpacket);
    167                 if (packet != null) {
    168                     doConsumePacket(packet);
    169                 }
    170             }
    171             log.trace("The socket peer is now closed");
    172             //doClose(new IOException("Socket peer is now closed"));
    173             stop();
    174         }
    175         catch (SessionDoneException e) {
    176             // this isn't really an exception, it just indicates
    177             // that the socket has closed normally
    178             log.trace("Session completed", e);
    179             stop();
    180         }
    181         catch (RMException ste) {
    182             doClose(ste);
    183         }
    184         catch (IOException e) {
    185             doClose(e);
    186         }
    187     }
    188
    189     /***
    190      * Can this wireformat process packets of this version
    191      * @param version the version number to test
    192      * @return true if can accept the version
    193      */
    194     public boolean canProcessWireFormatVersion(int version){
    195         return wireFormat.canProcessWireFormatVersion(version);
    196     }
    197
    198     /***
    199      * @return the current version of this wire format
    200      */
    201     public int getCurrentWireFormatVersion(){
    202         return wireFormat.getCurrentWireFormatVersion();
    203     }
    204
    205     protected DatagramPacket createDatagramPacket() {
    206         DatagramPacket answer = new DatagramPacket(new byte[SOCKET_BUFFER_SIZE], SOCKET_BUFFER_SIZE);
    207         answer.setPort(port);
    208         answer.setAddress(inetAddress);
    209         return answer;
    210     }
    211
    212     protected DatagramPacket createDatagramPacket(Packet packet) throws IOException, JMSException {
    213         DatagramPacket answer = wireFormat.writePacket(channelId, packet);
    214         answer.setPort(port);
    215         answer.setAddress(inetAddress);
    216         return answer;
    217     }
    218
    219     private void doClose(Exception ex) {
    220         if (!closed.get()) {
    221             JMSException jmsEx = new JMSException("Error reading socket: " + ex);
    222             jmsEx.setLinkedException(ex);
    223             onAsyncException(jmsEx);
    224             stop();
    225         }
    226     }
    227
    228     /***
    229      * pretty print for object
    230      *
    231      * @return String representation of this object
    232      */
    233     public String toString() {
    234         return "JRMSTransportChannel: " + socket;
    235     }
    236 }