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diff --git a/libjava/classpath/gnu/java/util/prefs/EventDispatcher.java b/libjava/classpath/gnu/java/util/prefs/EventDispatcher.java
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+/* EventDispatcher.java -- Dispatch events for prefs
+   Copyright (C) 2006 Free Software Foundation, Inc.
+
+This file is part of GNU Classpath.
+
+GNU Classpath 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, or (at your option)
+any later version.
+
+GNU Classpath 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 GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.java.util.prefs;
+
+import java.util.ArrayList;
+
+/**
+ * This is a helper class used for dispatching events for
+ * the prefs package.
+ */
+public class EventDispatcher extends Thread
+{
+  // This is a singleton class.  We dispatch all events via a
+  // new Thread which is created on demand.
+  private static final Thread dispatchThread = new EventDispatcher();
+
+  // This is a queue of events to dispatch.  This thread waits on
+  // the queue and when notified will remove events until the queue
+  // is empty.
+  private static final ArrayList queue = new ArrayList();
+
+  // FIXME: this thread probably ought to go in some classpath-internal
+  // ThreadGroup.  But we don't have that yet.
+  private EventDispatcher()
+  {
+    setDaemon(true);
+    start();
+  }
+
+  public void run()
+  {
+    while (true)
+      {
+        Runnable r;
+        synchronized (queue)
+          {
+            while (queue.size() == 0)
+              {
+                try
+                  {
+                    wait();
+                  }
+                catch (InterruptedException _)
+                  {
+                    // Ignore.
+                  }
+              }
+            r = (Runnable) queue.remove(0);
+          }
+        // Invoke outside the synchronization, so that 
+        // we aren't blocking other threads from posting events.
+        try
+          {
+            r.run();
+          }
+        catch (Throwable _)
+          {
+            // Ignore.
+          }
+      }
+  }
+
+  /**
+   * Add a new runnable to the event dispatch queue.  The
+   * runnable will be invoked in the event dispatch queue
+   * without any locks held.
+   * @param runner the Runnable to dispatch
+   */
+  public static void dispatch(Runnable runner)
+  {
+    synchronized (queue)
+      {
+        queue.add(runner);
+      }
+  }
+}