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45 lines
1.0 KiB
45 lines
1.0 KiB
8 years ago
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/*
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* Copyright (c) 2016 - present Facebook, Inc.
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* All rights reserved.
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*
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* This source code is licensed under the BSD style license found in the
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* LICENSE file in the root directory of this source tree. An additional grant
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* of patent rights can be found in the PATENTS file in the same directory.
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*/
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import javax.annotation.concurrent.ThreadSafe;
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@ThreadSafe
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public class Constructors {
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int field;
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static Object staticField;
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public Constructors(int i) {
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field = i; // ok
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}
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public Constructors() {
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staticField = new Object(); // not ok;
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}
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private Constructors(Object o) {
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staticField = o; // ok because this is private
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}
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public Constructors(Constructors o) {
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o.field = 42; // not ok
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}
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public static synchronized Constructors singletonOk() {
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// ok because lock is held during write to static field in constructor
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return new Constructors(new Object());
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}
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public static Constructors singletonBad() {
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// not ok because no lock is held
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return new Constructors(new Object());
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}
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}
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