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diff --git a/cli_ure/source/ure/uno/util/WeakAdapter.cs b/cli_ure/source/ure/uno/util/WeakAdapter.cs
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+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+using System;
+using unoidl.com.sun.star.uno;
+using unoidl.com.sun.star.lang;
+
+namespace uno.util
+{
+    
+/** An XAdapter implementation that holds a weak reference
+    (System.WeakReference) to an object.
+    Clients can register listeners (unoidl.com.sun.star.lang.XReference)
+    which are notified when the object (the one which is kept weak) is
+    being finalized.  That is, that object is being destroyed because there
+    are not any hard references to it.
+*/
+public class WeakAdapter : XAdapter
+{
+    // references the XWeak implementation
+    private WeakReference m_weakRef;
+    // contains XReference objects registered by addReference
+    private delegate void XReference_dispose();
+    private XReference_dispose m_XReference_dispose;
+    
+    /** ctor.
+        
+        @param obj the object that is to be held weakly
+    */
+    public WeakAdapter( Object obj )
+    {
+        m_weakRef = new WeakReference( obj );
+        m_XReference_dispose = null;
+    }
+    
+    /** Called by the XWeak implementation (WeakBase) when it is being
+        finalized.  It is only being called once.
+        The registererd XReference listeners are notified. On notification
+        they are  to unregister themselves. The notification is thread-safe.
+        However, it is possible to add a listener during the notification
+        process, which will never receive a notification.
+        To prevent this, one would have to synchronize this method with 
+        the addReference method. But this can result in deadlocks in a
+        multithreaded environment.
+    */
+    internal /* non-virtual */ void referentDying()
+    {
+        XReference_dispose call;
+        lock (this)
+        {
+            call = m_XReference_dispose;
+            m_XReference_dispose = null;
+        }
+        if (null != call)
+            call();
+    }
+    
+    // XAdapter impl
+    
+    /** Called to obtain a hard reference o the object which is kept weakly
+        by this instance.
+        
+        @return hard reference to the object
+    */
+    public Object queryAdapted()
+    {
+        return m_weakRef.Target;
+    }
+    /** Called by clients to register listener which are notified when the
+        weak object is dying.
+        
+        @param xReference a listener
+    */
+    public void removeReference( XReference xReference )
+    {
+        lock (this)
+        {
+            m_XReference_dispose -=
+                new XReference_dispose( xReference.dispose );
+        }
+    }
+    /** Called by clients to unregister listeners.
+        
+        @param xReference a listener
+    */
+    public void addReference( XReference xReference )
+    {
+        lock (this)
+        {
+            m_XReference_dispose +=
+                new XReference_dispose( xReference.dispose );
+        }
+    }
+}
+
+}