DiscoveryTransportChannel 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;
    19
    20  import org.apache.commons.logging.Log;
    21  import org.apache.commons.logging.LogFactory;
    22  import org.codehaus.activemq.ConfigurationException;
    23  import org.codehaus.activemq.message.WireFormat;
    24  import org.codehaus.activemq.transport.reliable.ReliableTransportChannel;
    25  import org.codehaus.activemq.util.Callback;
    26  import org.codehaus.activemq.util.ExceptionTemplate;
    27  import org.codehaus.activemq.util.MapHelper;
    28
    29  import javax.jms.JMSException;
    30  import java.net.URI;
    31  import java.net.URISyntaxException;
    32  import java.util.List;
    33  import java.util.Map;
    34
    35  /***
    36   * A {@link ReliableTransportChannel} which uses a {@link DiscoveryAgent} to discover remote broker
    37   * instances and dynamically connect to them.
    38   *
    39   * @version $Revision: 1.3 $
    40   */
    41  public class DiscoveryTransportChannel extends ReliableTransportChannel implements DiscoveryListener {
    42      private static final Log log = LogFactory.getLog(DiscoveryTransportChannel.class);
    43
    44
    45      private DiscoveryAgent discoveryAgent;
    46      private String remoteUserName;
    47      private String remotePassword;
    48
    49
    50      public DiscoveryTransportChannel(WireFormat wireFormat, DiscoveryAgent discoveryAgent) {
    51          super(wireFormat);
    52          this.discoveryAgent = discoveryAgent;
    53      }
    54
    55      public void start() throws JMSException {
    56          if (discoveryAgent == null) {
    57              throw new ConfigurationException("Must be configured with a discoveryAgent property");
    58          }
    59
    60          // lets pass into the agent the broker name and connection details
    61          discoveryAgent.setDiscoveryListener(this);
    62          discoveryAgent.start();
    63
    64          super.start();
    65      }
    66
    67      public void stop() {
    68          ExceptionTemplate template = new ExceptionTemplate();
    69          template.run(new Callback() {
    70              public void execute() throws Throwable {
    71                  discoveryAgent.stop();
    72              }
    73          });
    74          template.run(new Callback() {
    75              public void execute() throws Throwable {
    76                  DiscoveryTransportChannel.super.stop();
    77              }
    78          });
    79          Throwable e = template.getFirstException();
    80          log.warn("Failed to stop the transport channel cleanly due to: " + e, e);
    81      }
    82
    83
    84      public synchronized void addService(DiscoveryEvent event) {
    85          Map details = event.getServiceDetails();
    86          String url = MapHelper.getString(details, "connectURL");
    87          if (url != null) {
    88              try {
    89                  URI uri = new URI(url);
    90                  List urlList = getUris();
    91                  if (!urlList.contains(uri)) {
    92                      log.info("Adding new broker connection URL: " + uri + " with details: " + details);
    93
    94                      urlList.add(uri);
    95                  }
    96              }
    97              catch (URISyntaxException e) {
    98                  log.warn("Could not connect to remote URI: " + url + " due to bad URI syntax: " + e, e);
    99              }
    100         }
    101     }
    102
    103     public synchronized void removeService(DiscoveryEvent event) {
    104         Map details = event.getServiceDetails();
    105         String url = MapHelper.getString(details, "connectURL");
    106         if (url != null) {
    107             try {
    108                 URI uri = new URI(url);
    109                 synchronized (this) {
    110                     List urlList = getUris();
    111                     if (urlList.remove(uri)) {
    112                         log.info("Removing broker connection URL: " + uri);
    113                     }
    114                 }
    115             }
    116             catch (URISyntaxException e) {
    117                 log.warn("Could not remove remote URI: " + url + " due to bad URI syntax: " + e, e);
    118             }
    119         }
    120     }
    121
    122     // Properties
    123     //-------------------------------------------------------------------------
    124     public DiscoveryAgent getDiscoveryAgent() {
    125         return discoveryAgent;
    126     }
    127
    128     public void setDiscoveryAgent(DiscoveryAgent discoveryAgent) {
    129         this.discoveryAgent = discoveryAgent;
    130     }
    131
    132
    133     public String getRemotePassword() {
    134         return remotePassword;
    135     }
    136
    137     public void setRemotePassword(String remotePassword) {
    138         this.remotePassword = remotePassword;
    139     }
    140
    141     public String getRemoteUserName() {
    142         return remoteUserName;
    143     }
    144
    145     public void setRemoteUserName(String remoteUserName) {
    146         this.remoteUserName = remoteUserName;
    147     }
    148
    149 }