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From-SVN: r102074

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diff --git a/libjava/classpath/java/lang/ref/PhantomReference.java b/libjava/classpath/java/lang/ref/PhantomReference.java
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+/* java.lang.ref.PhantomReference
+   Copyright (C) 1999 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 java.lang.ref;
+
+/**
+ * A phantom reference is useful, to get notified, when an object got
+ * finalized.  You can't access that object though, since it is
+ * finalized.  This is the reason, why <code>get()</code> always
+ * returns null.
+ *
+ * @author Jochen Hoenicke 
+ */
+public class PhantomReference 
+  extends Reference
+{
+  /**
+   * Creates a new phantom reference.
+   * @param referent the object that should be watched.
+   * @param q the queue that should be notified, if the referent was
+   * finalized.  This mustn't be <code>null</code>.
+   * @exception NullPointerException if q is null.
+   */
+  public PhantomReference(Object referent, ReferenceQueue q)
+  {
+    super(referent, q);
+  }
+  
+  /**
+   * Returns the object, this reference refers to.
+   * @return <code>null</code>, since the refered object may be
+   * finalized and thus not accessible.  
+   */
+  public Object get()
+  {
+    return null;
+  }
+}