Initial version. JM-1121

git-svn-id: http://svn.igniterealtime.org/svn/repos/openfire/trunk@9155 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/openfire/user/RemotePresenceEventDispatcher.java

+/**
+ * $RCSfile$
+ * $Revision: $
+ * $Date: $
+ *
+ * Copyright (C) 2007 Jive Software. All rights reserved.
+ *
+ * This software is published under the terms of the GNU Public License (GPL),
+ * a copy of which is included in this distribution.
+ */
+
+package org.jivesoftware.openfire.user;
+
+import org.xmpp.packet.Presence;
+
+import java.util.List;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+/**
+ * Dispatches presence events of remote users. The following events are supported:
+ * <ul>
+ * <li><b>remoteUserAvailable</b> --> A remote user is now available.</li>
+ * <li><b>remoteUserUnavailable</b> --> A remote user is no longer available.</li>
+ * </ul>
+ * Use {@link #addListener(RemotePresenceEventListener)} and
+ * {@link #removeListener(RemotePresenceEventListener)} to add or remove {@link RemotePresenceEventListener}.
+ *
+ * @author Armando Jagucki
+ */
+public class RemotePresenceEventDispatcher {
+
+    private static List<RemotePresenceEventListener> listeners =
+            new CopyOnWriteArrayList<RemotePresenceEventListener>();
+
+    /**
+     * Registers a listener to receive events.
+     *
+     * @param listener the listener.
+     */
+    public static void addListener(RemotePresenceEventListener listener) {
+        if (listener == null) {
+            throw new NullPointerException();
+        }
+        listeners.add(listener);
+    }
+
+    /**
+     * Unregisters a listener to receive events.
+     *
+     * @param listener the listener.
+     */
+    public static void removeListener(RemotePresenceEventListener listener) {
+        listeners.remove(listener);
+    }
+
+    /**
+     * Notification message indicating that a remote user is now available or has changed
+     * his available presence. This event is triggered when an available presence is received
+     * by <tt>PresenceRouter</tt>.
+     *
+     * @param presence the received available presence.
+     */
+    public static void remoteUserAvailable(Presence presence) {
+        if (!listeners.isEmpty()) {
+            for (RemotePresenceEventListener listener : listeners) {
+                listener.remoteUserAvailable(presence);
+            }
+        }
+    }
+
+    /**
+     * Notification message indicating that a remote user that was available is no longer
+     * available. A remote user becomes unavailable when an unavailable presence is received.
+     * by <tt>PresenceRouter</tt>.
+     *
+     * @param presence the received unavailable presence.
+     */
+    public static void remoteUserUnavailable(Presence presence) {
+        if (!listeners.isEmpty()) {
+            for (RemotePresenceEventListener listener : listeners) {
+                listener.remoteUserUnavailable(presence);
+            }
+        }
+    }
+
+}

src/java/org/jivesoftware/openfire/user/RemotePresenceEventListener.java

+/**
+ * $RCSfile$
+ * $Revision: $
+ * $Date: $
+ *
+ * Copyright (C) 2007 Jive Software. All rights reserved.
+ *
+ * This software is published under the terms of the GNU Public License (GPL),
+ * a copy of which is included in this distribution.
+ */
+
+package org.jivesoftware.openfire.user;
+
+import org.xmpp.packet.Presence;
+
+/**
+ * Interface to listen for presence events of remote users. Use the
+ * {@link RemotePresenceEventDispatcher#addListener(RemotePresenceEventListener)}
+ * method to register for events.
+ *
+ * @author Armando Jagucki
+ */
+public interface RemotePresenceEventListener {
+
+    /**
+     * Notification message indicating that a remote user is now available or has changed
+     * his available presence. This event is triggered when an available presence is received
+     * by <tt>PresenceRouter</tt>.
+     *
+     * @param presence the received available presence.
+     */
+    public void remoteUserAvailable(Presence presence);
+
+    /**
+     * Notification message indicating that a remote user is no longer available.
+     * A remote user becomes unavailable when an unavailable presence is received.
+     * by <tt>PresenceRouter</tt>.
+     *
+     * @param presence the received unavailable presence.
+     */
+    public void remoteUserUnavailable(Presence presence);
+
+}