1.1 --- a/emul/compact/src/main/java/java/lang/ref/PhantomReference.java	Tue Feb 26 14:55:55 2013 +0100
     1.2 +++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.3 @@ -1,83 +0,0 @@
     1.4 -/*
     1.5 - * Copyright (c) 1997, 2003, Oracle and/or its affiliates. All rights reserved.
     1.6 - * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     1.7 - *
     1.8 - * This code is free software; you can redistribute it and/or modify it
     1.9 - * under the terms of the GNU General Public License version 2 only, as
    1.10 - * published by the Free Software Foundation.  Oracle designates this
    1.11 - * particular file as subject to the "Classpath" exception as provided
    1.12 - * by Oracle in the LICENSE file that accompanied this code.
    1.13 - *
    1.14 - * This code is distributed in the hope that it will be useful, but WITHOUT
    1.15 - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    1.16 - * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    1.17 - * version 2 for more details (a copy is included in the LICENSE file that
    1.18 - * accompanied this code).
    1.19 - *
    1.20 - * You should have received a copy of the GNU General Public License version
    1.21 - * 2 along with this work; if not, write to the Free Software Foundation,
    1.22 - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    1.23 - *
    1.24 - * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    1.25 - * or visit www.oracle.com if you need additional information or have any
    1.26 - * questions.
    1.27 - */
    1.28 -
    1.29 -package java.lang.ref;
    1.30 -
    1.31 -
    1.32 -/**
    1.33 - * Phantom reference objects, which are enqueued after the collector
    1.34 - * determines that their referents may otherwise be reclaimed.  Phantom
    1.35 - * references are most often used for scheduling pre-mortem cleanup actions in
    1.36 - * a more flexible way than is possible with the Java finalization mechanism.
    1.37 - *
    1.38 - * <p> If the garbage collector determines at a certain point in time that the
    1.39 - * referent of a phantom reference is <a
    1.40 - * href="package-summary.html#reachability">phantom reachable</a>, then at that
    1.41 - * time or at some later time it will enqueue the reference.
    1.42 - *
    1.43 - * <p> In order to ensure that a reclaimable object remains so, the referent of
    1.44 - * a phantom reference may not be retrieved: The <code>get</code> method of a
    1.45 - * phantom reference always returns <code>null</code>.
    1.46 - *
    1.47 - * <p> Unlike soft and weak references, phantom references are not
    1.48 - * automatically cleared by the garbage collector as they are enqueued.  An
    1.49 - * object that is reachable via phantom references will remain so until all
    1.50 - * such references are cleared or themselves become unreachable.
    1.51 - *
    1.52 - * @author   Mark Reinhold
    1.53 - * @since    1.2
    1.54 - */
    1.55 -
    1.56 -public class PhantomReference<T> extends Reference<T> {
    1.57 -
    1.58 -    /**
    1.59 -     * Returns this reference object's referent.  Because the referent of a
    1.60 -     * phantom reference is always inaccessible, this method always returns
    1.61 -     * <code>null</code>.
    1.62 -     *
    1.63 -     * @return  <code>null</code>
    1.64 -     */
    1.65 -    public T get() {
    1.66 -        return null;
    1.67 -    }
    1.68 -
    1.69 -    /**
    1.70 -     * Creates a new phantom reference that refers to the given object and
    1.71 -     * is registered with the given queue.
    1.72 -     *
    1.73 -     * <p> It is possible to create a phantom reference with a <tt>null</tt>
    1.74 -     * queue, but such a reference is completely useless: Its <tt>get</tt>
    1.75 -     * method will always return null and, since it does not have a queue, it
    1.76 -     * will never be enqueued.
    1.77 -     *
    1.78 -     * @param referent the object the new phantom reference will refer to
    1.79 -     * @param q the queue with which the reference is to be registered,
    1.80 -     *          or <tt>null</tt> if registration is not required
    1.81 -     */
    1.82 -    public PhantomReference(T referent, ReferenceQueue<? super T> q) {
    1.83 -        super(referent, q);
    1.84 -    }
    1.85 -
    1.86 -}