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diff --git a/jurt/com/sun/star/uno/WeakReference.java b/jurt/com/sun/star/uno/WeakReference.java
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+/*************************************************************************
+ *
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * Copyright 2000, 2010 Oracle and/or its affiliates.
+ *
+ * OpenOffice.org - a multi-platform office productivity suite
+ *
+ * This file is part of OpenOffice.org.
+ *
+ * OpenOffice.org is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 3
+ * only, as published by the Free Software Foundation.
+ *
+ * OpenOffice.org 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 version 3 for more details
+ * (a copy is included in the LICENSE file that accompanied this code).
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * version 3 along with OpenOffice.org.  If not, see
+ * <http://www.openoffice.org/license.html>
+ * for a copy of the LGPLv3 License.
+ *
+ ************************************************************************/
+
+package com.sun.star.uno;
+
+import com.sun.star.uno.XWeak;
+import com.sun.star.uno.UnoRuntime;
+import com.sun.star.uno.XAdapter;
+import com.sun.star.uno.XReference;
+
+/** This class holds weak reference to an object. It actually holds a reference to a
+    com.sun.star.XAdapter implementation and obtains a hard reference if necessary.
+ */
+public class WeakReference
+{
+    private final boolean DEBUG= false;
+    private OWeakRefListener m_listener;
+    // There is no default constructor. Every instance must register itself with the
+    // XAdapter interface, which is done in the constructors. Assume we have this code
+    // WeakReference ref= new WeakReference();
+    // ref = someOtherWeakReference;
+    //
+    // ref would not be notified (XReference.dispose()) because it did not register
+    // itself. Therefore the XAdapter would be kept aliver although this is not
+    // necessary.
+
+    /** Creates an instance of this class.
+     *@param obj - another instance that is to be copied
+     */
+    public WeakReference(WeakReference obj)
+    {
+        if (obj != null)
+        {
+            Object weakImpl= obj.get();
+            if (weakImpl != null)
+            {
+                XWeak weak= UnoRuntime.queryInterface(XWeak.class, weakImpl);
+                if (weak != null)
+                {
+                    XAdapter adapter= (XAdapter) weak.queryAdapter();
+                    if (adapter != null)
+                        m_listener= new OWeakRefListener(adapter);
+                }
+            }
+        }
+    }
+
+    /** Creates an instance of this class.
+     *@param obj XWeak implementation
+     */
+    public WeakReference(Object obj)
+    {
+        XWeak weak= UnoRuntime.queryInterface(XWeak.class, obj);
+        if (weak != null)
+        {
+            XAdapter adapter= (XAdapter) weak.queryAdapter();
+            if (adapter != null)
+                m_listener= new OWeakRefListener(adapter);
+        }
+    }
+    /** Returns a hard reference to the object that is kept weak by this class.
+     *@return a hard reference to the XWeak implementation.
+     */
+    public Object get()
+    {
+        if (m_listener != null)
+            return m_listener.get();
+        return null;
+    }
+}
+
+/** Implementation of com.sun.star.uno.XReference for use with WeakReference.
+ *  It keeps the XAdapter implementation and registers always with it. Deregistering
+ *  occurs on notification by the adapter and the adapter is released.
+ */
+class OWeakRefListener implements XReference
+{
+    private final boolean DEBUG= false;
+    private XAdapter m_adapter;
+
+    /** The constructor registered this object with adapter.
+     *@param adapter the XAdapter implementation.
+     */
+    OWeakRefListener( XAdapter adapter)
+    {
+        m_adapter= adapter;
+        m_adapter.addReference(this);
+    }
+    /** Method of com.sun.star.uno.XReference. When called, it deregisteres this
+     *  object with the adapter and releases the reference to it.
+     */
+    synchronized public void dispose()
+    {
+        if (m_adapter != null)
+        {
+            m_adapter.removeReference(this);
+            m_adapter= null;
+        }
+    }
+
+    /** Obtains a hard reference to the object which is kept weak by the adapter
+     *  and returns it.
+     *  @return hard reference to the otherwise weakly kept object.
+     */
+    synchronized Object get()
+    {
+        Object retVal= null;
+        if (m_adapter != null)
+        {
+            retVal= m_adapter.queryAdapted();
+            if (retVal == null)
+            {
+                // If this object registered as listener with XAdapter while it was notifying
+                // the listeners then this object might not have been notified. If queryAdapted
+                // returned null then the weak kept object is dead and the listeners have already
+                // been notified. And we missed it.
+                m_adapter.removeReference(this);
+                m_adapter= null;
+            }
+        }
+        return retVal;
+    }
+}