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.
20  *
21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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24  */
25 
26 package jdk.internal.vm.annotation;
27 
28 import java.lang.annotation.*;
29 
30 /**
31  * A loosely-consistent value class is a class that is willing to tolerate
32  * data corruption when fields or arrays storing instances of the class are
33  * updated under race. Specifically, a value object read from such a field may
34  * contain combinations of field values that were never set by a previous
35  * constructor invocation.
36  * <p>
37  * Users of a class with this annotation take responsibility for ensuring the
38  * integrity of their data by avoiding race conditions.
39  * <p>
40  * The HotSpot VM uses this annotation to enable non-atomic strategies for
41  * reading and writing to flattened fields and arrays of the annotated class's
42  * type.
43  * <p>
44  * Because these behaviors are not specified by Java SE, this annotation should
45  * only be used by internal JDK code for experimental purposes and should not
46  * affect user-observable outcomes.
47  */
48 @Target(ElementType.TYPE)
49 @Retention(RetentionPolicy.RUNTIME)
50 public @interface LooselyConsistentValue {
51 }