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1   /***
2    *  Copyright 2003-2010 Terracotta, Inc.
3    *
4    *  Licensed under the Apache License, Version 2.0 (the "License");
5    *  you may not use this file except in compliance with the License.
6    *  You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   *  Unless required by applicable law or agreed to in writing, software
11   *  distributed under the License is distributed on an "AS IS" BASIS,
12   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   *  See the License for the specific language governing permissions and
14   *  limitations under the License.
15   */
16  
17  package net.sf.ehcache.distribution;
18  
19  import net.sf.ehcache.CacheException;
20  import net.sf.ehcache.CacheManager;
21  import net.sf.ehcache.util.PropertyUtil;
22  
23  import java.io.IOException;
24  import java.net.InetAddress;
25  import java.util.Properties;
26  import java.util.StringTokenizer;
27  
28  import org.slf4j.Logger;
29  import org.slf4j.LoggerFactory;
30  
31  /***
32   * Builds a factory based on RMI
33   *
34   * @author Greg Luck
35   * @version $Id: RMICacheManagerPeerProviderFactory.html 13146 2011-08-01 17:12:39Z oletizi $
36   */
37  public class RMICacheManagerPeerProviderFactory extends CacheManagerPeerProviderFactory {
38  
39      private static final Logger LOG = LoggerFactory.getLogger(RMICacheManagerPeerProviderFactory.class.getName());
40  
41      private static final String HOST_NAME = "hostName";
42      private static final String PEER_DISCOVERY = "peerDiscovery";
43      private static final String AUTOMATIC_PEER_DISCOVERY = "automatic";
44      private static final String MANUALLY_CONFIGURED_PEER_DISCOVERY = "manual";
45      private static final String RMI_URLS = "rmiUrls";
46      private static final String MULTICAST_GROUP_PORT = "multicastGroupPort";
47      private static final String MULTICAST_GROUP_ADDRESS = "multicastGroupAddress";
48      private static final String MULTICAST_PACKET_TTL = "timeToLive";
49      private static final int MAXIMUM_TTL = 255;
50  
51  
52      /***
53       * @param properties implementation specific properties. These are configured as comma
54       *                   separated name value pairs in ehcache.xml
55       */
56      public CacheManagerPeerProvider createCachePeerProvider(CacheManager cacheManager, Properties properties)
57              throws CacheException {
58          String peerDiscovery = PropertyUtil.extractAndLogProperty(PEER_DISCOVERY, properties);
59          if (peerDiscovery == null || peerDiscovery.equalsIgnoreCase(AUTOMATIC_PEER_DISCOVERY)) {
60              try {
61                  return createAutomaticallyConfiguredCachePeerProvider(cacheManager, properties);
62              } catch (IOException e) {
63                  throw new CacheException("Could not create CacheManagerPeerProvider. Initial cause was " + e.getMessage(), e);
64              }
65          } else if (peerDiscovery.equalsIgnoreCase(MANUALLY_CONFIGURED_PEER_DISCOVERY)) {
66              return createManuallyConfiguredCachePeerProvider(properties);
67          } else {
68              return null;
69          }
70      }
71  
72  
73      /***
74       * peerDiscovery=manual, rmiUrls=//hostname:port/cacheName //hostname:port/cacheName //hostname:port/cacheName
75       */
76      protected CacheManagerPeerProvider createManuallyConfiguredCachePeerProvider(Properties properties) {
77          String rmiUrls = PropertyUtil.extractAndLogProperty(RMI_URLS, properties);
78          if (rmiUrls == null || rmiUrls.length() == 0) {
79              LOG.info("Starting manual peer provider with empty list of peers. " +
80                      "No replication will occur unless peers are added.");
81              rmiUrls = "";
82          }
83          rmiUrls = rmiUrls.trim();
84          StringTokenizer stringTokenizer = new StringTokenizer(rmiUrls, PayloadUtil.URL_DELIMITER);
85          RMICacheManagerPeerProvider rmiPeerProvider = new ManualRMICacheManagerPeerProvider();
86          while (stringTokenizer.hasMoreTokens()) {
87              String rmiUrl = stringTokenizer.nextToken();
88              rmiUrl = rmiUrl.trim();
89              rmiPeerProvider.registerPeer(rmiUrl);
90  
91                  LOG.debug("Registering peer {}", rmiUrl);
92          }
93          return rmiPeerProvider;
94      }
95  
96      /***
97       * peerDiscovery=automatic, multicastGroupAddress=230.0.0.1, multicastGroupPort=4446, multicastPacketTimeToLive=255
98       */
99      protected CacheManagerPeerProvider createAutomaticallyConfiguredCachePeerProvider(CacheManager cacheManager,
100                                                                                       Properties properties) throws IOException {
101         String hostName = PropertyUtil.extractAndLogProperty(HOST_NAME, properties);
102         InetAddress hostAddress = null;
103         if (hostName != null && hostName.length() != 0) {
104             hostAddress = InetAddress.getByName(hostName);
105             if (hostName.equals("localhost")) {
106                 LOG.warn("Explicitly setting the multicast hostname to 'localhost' is not recommended. "
107                         + "It will only work if all CacheManager peers are on the same machine.");
108             }
109         }
110 
111 
112         String groupAddressString = PropertyUtil.extractAndLogProperty(MULTICAST_GROUP_ADDRESS, properties);
113         InetAddress groupAddress = InetAddress.getByName(groupAddressString);
114         String multicastPortString = PropertyUtil.extractAndLogProperty(MULTICAST_GROUP_PORT, properties);
115         Integer multicastPort = Integer.valueOf(multicastPortString);
116         String packetTimeToLiveString = PropertyUtil.extractAndLogProperty(MULTICAST_PACKET_TTL, properties);
117         Integer timeToLive;
118         if (packetTimeToLiveString == null) {
119             timeToLive = Integer.valueOf(1);
120             LOG.debug("No TTL set. Setting it to the default of 1, which means packets are limited to the same subnet.");
121         } else {
122             timeToLive = Integer.valueOf(packetTimeToLiveString);
123             if (timeToLive.intValue() < 0 || timeToLive.intValue() > MAXIMUM_TTL) {
124                 throw new CacheException("The TTL must be set to a value between 0 and 255");
125             }
126         }
127         return new MulticastRMICacheManagerPeerProvider(cacheManager, groupAddress, multicastPort, timeToLive, hostAddress);
128     }
129 }