Messaging facade for clustered communications to allow implementations from JGroups or Hazelcast to be used.

* PropertyBackedBeanExporter uses the facade, configured with JGroups messaging implementation.
* Unfortunately, some remodelling required before this will work with Ehcache's CacheManagerPeerProviderFactory




git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@33830 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/repo/cluster/Messenger.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2005-2012 Alfresco Software Limited.
+ *
+ * This file is part of Alfresco
+ *
+ * Alfresco is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Alfresco is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.alfresco.repo.cluster;
+
+import java.io.Serializable;
+
+/**
+ * Provides facilities for peer-to-peer messaging within a cluster. This interface
+ * is intended to act as a facade, allowing the actual implementation (e.g. JGroups
+ * or Hazelcast) to be decoupled as much as possible from the Alfresco code base.
+ * <p>
+ * Instances of this class are parameterised with the type of message payload
+ * to send and receive.
+ * 
+ * @author Matt Ward
+ */
+public interface Messenger<T extends Serializable>
+{
+    void send(T message);
+    
+    void setReceiver(MessageReceiver<T> receiver);
+    
+    boolean isConnected();
+}