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diff --git a/libjava/gnu/java/io/ObjectIdentityWrapper.java b/libjava/gnu/java/io/ObjectIdentityWrapper.java
new file mode 100644
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+++ b/libjava/gnu/java/io/ObjectIdentityWrapper.java
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+/* ObjectIdentityWrapper.java -- Wrapper class used to override equals()
+    and hashCode() to be as discriminating as possible
+   Copyright (C) 1998 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., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 USA.
+
+As a special exception, if you link this library with other files to
+produce an executable, this library does not by itself cause the
+resulting executable to be covered by the GNU General Public License.
+This exception does not however invalidate any other reasons why the
+executable file might be covered by the GNU General Public License. */
+
+
+package gnu.java.io;
+
+/**
+   This class is a thin wrapper around <code>Object</code> that makes
+   the methods <code>hashCode()</code> and <code>equals(Object)</code>
+   as discriminating as possible.
+*/
+public class ObjectIdentityWrapper
+{
+
+  /**
+     Constructs a <code>ObjectIdentityWrapper</code> that is wrapped
+     around o.
+  */
+  public ObjectIdentityWrapper( Object o )
+  {
+    object = o;
+  }
+
+  /**
+     Uses <code>System.identityHashCode(Object)</code> to compute a
+     hash code for the object wrapped by this
+     <code>ObjectIdentityWrapper</code>.
+
+     @see java.lang.System#identityHashCode(java.lang.Object)
+     @see java.util.Hashtable
+     @see java.lang.Object#hashCode()
+  */
+  public int hashCode()
+  {
+    return System.identityHashCode( object );
+  }
+
+  /**
+     Uses the <code>==</code> operator to test for equality between
+     the object wrapped by this <code>ObjectIdentityWrapper</code> and
+     the object wrapped by the <code>ObjectIdentityWrapper</code> o.
+     Returns false if o is not a <code>ObjectIdentityWrapper</code>.
+
+     @see java.util.Hashtable
+     @see java.lang.Object#equals()
+  */
+  public boolean equals( Object o )
+  {
+    if( o instanceof ObjectIdentityWrapper )
+      return object == ((ObjectIdentityWrapper)o).object;
+    else
+      return false;
+  }
+
+  public String toString()
+  {
+    return "ObjectIdentityWrapper< " + object + ", " + hashCode() + " >";
+  }
+
+  /**
+     The <code>Object</code> wrapped by this
+     <code>ObjectIdentityWrapper</code>.
+  */
+  public Object object;
+}