1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
5  * This code is free software; you can redistribute it and/or modify it
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7  * published by the Free Software Foundation.  Oracle designates this
8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
10  *
11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
18  * 2 along with this work; if not, write to the Free Software Foundation,
19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24  */
25 
26 package jdk.internal.ref;
27 
28 import java.lang.ref.Cleaner;
29 
30 /**
31  * CleanerFactory provides a Cleaner for use within system modules.
32  * The cleaner is created on the first reference to the CleanerFactory.
33  */
34 public final class CleanerFactory {
35 
36     /* The common Cleaner. */
37     // Android-changed: objects registered in the system cleaner are cleaned
38     // by the finalizer daemon thread, not in a InnocuousThread.
39     /*
40     private final static Cleaner commonCleaner = Cleaner.create(new ThreadFactory() {
41         @Override
42         public Thread newThread(Runnable r) {
43             return AccessController.doPrivileged(new PrivilegedAction<>() {
44                 @Override
45                 public Thread run() {
46                     Thread t = InnocuousThread.newSystemThread("Common-Cleaner", r);
47                     t.setPriority(Thread.MAX_PRIORITY - 2);
48                     return t;
49                 }
50             });
51         }
52     });
53     */
54     private static final Cleaner commonCleaner = Cleaner.createSystemCleaner();
55 
56     /**
57      * Cleaner for use within system modules.
58      *
59      * This Cleaner will run on a thread whose context class loader
60      * is {@code null}. The system cleaning action to perform in
61      * this Cleaner should handle a {@code null} context class loader.
62      *
63      * @return a Cleaner for use within system modules
64      */
cleaner()65     public static Cleaner cleaner() {
66         return commonCleaner;
67     }
68 }
69