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+/* java.lang.ref.WeakReference
+ 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., 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 java.lang.ref;
+
+/**
+ * A weak reference will be cleared, if the object is only weakly
+ * reachable. It is useful for lookup tables, where you aren't
+ * interested in an entry, if the key isn't reachable anymore.
+ * <code>WeakHashtable</code> is a complete implementation of such a
+ * table. <br>
+ *
+ * It is also useful to make objects unique: You create a set of weak
+ * references to those objects, and when you create a new object you
+ * look in this set, if the object already exists and return it. If
+ * an object is not referenced anymore, the reference will
+ * automatically cleared, and you may remove it from the set. <br>
+ *
+ * @author Jochen Hoenicke
+ * @see java.util.WeakHashtable
+ */
+public class WeakReference
+ extends Reference
+{
+ /**
+ * Create a new weak reference, that is not registered to any queue.
+ * @param referent the object we refer to.
+ */
+ public WeakReference(Object referent)
+ {
+ super(referent);
+ }
+
+ /**
+ * Create a new weak reference.
+ * @param referent the object we refer to.
+ * @param q the reference queue to register on.
+ * @exception NullPointerException if q is null.
+ */
+ public WeakReference(Object referent, ReferenceQueue q)
+ {
+ super(referent, q);
+ }
+}
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