From ff78f93763d7104f4c33beb8b8fa8bbd11eaf5d3 Mon Sep 17 00:00:00 2001
From: =?utf8?q?David=20=E2=80=98Bombe=E2=80=99=20Roden?=
 <bombe@pterodactylus.net>
Date: Wed, 12 Nov 2008 22:30:04 +0100
Subject: [PATCH] Add ListenerSupport class.

---
 .../pterodactylus/util/event/ListenerSupport.java  | 102 +++++++++++++++++++++
 1 file changed, 102 insertions(+)
 create mode 100644 src/net/pterodactylus/util/event/ListenerSupport.java

diff --git a/src/net/pterodactylus/util/event/ListenerSupport.java b/src/net/pterodactylus/util/event/ListenerSupport.java
new file mode 100644
index 0000000..1b11296
--- /dev/null
+++ b/src/net/pterodactylus/util/event/ListenerSupport.java
@@ -0,0 +1,102 @@
+/*
+ * jSite-next - ListenerSupport.java -
+ * Copyright © 2008 David Roden
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+package net.pterodactylus.util.event;
+
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Helper class to ease listener management.
+ *
+ * @param <S>
+ *            The type of the source
+ * @param <L>
+ *            The type of the listeners
+ * @author David ‘Bombe’ Roden &lt;bombe@freenetproject.org&gt;
+ */
+public class ListenerSupport<S, L> {
+
+	/** The source of the events. */
+	private final S source;
+
+	/** The list of registered listeners. */
+	private final List<L> listeners = new ArrayList<L>();
+
+	/**
+	 * Creates a new listener support.
+	 *
+	 * @param source
+	 *            The source of all events
+	 */
+	public ListenerSupport(S source) {
+		this.source = source;
+	}
+
+	/**
+	 * Adds a listener to the list of registered listeners.
+	 *
+	 * @param listener
+	 *            The listener to add
+	 */
+	public void addListener(L listener) {
+		synchronized (listeners) {
+			listeners.add(listener);
+		}
+	}
+
+	/**
+	 * Removes a listener from the list of registered listeners.
+	 *
+	 * @param listener
+	 *            The listener to remove
+	 */
+	public void removeListener(L listener) {
+		synchronized (listeners) {
+			listeners.remove(listener);
+		}
+	}
+
+	//
+	// PROTECTED METHODS
+	//
+
+	/**
+	 * Returns the source of all events.
+	 *
+	 * @return The source of all events
+	 */
+	protected S getSource() {
+		return source;
+	}
+
+	/**
+	 * Returns a list of all listeners. This list is a copy of the internally
+	 * kept list and as thus will not be modified by calls to
+	 * {@link #addListener(Object)} or {@link #removeListener(Object)}.
+	 *
+	 * @return The list of all listeners
+	 */
+	protected List<L> getListeners() {
+		synchronized (listeners) {
+			return new ArrayList<L>(listeners);
+		}
+	}
+
+}
-- 
2.7.4