28 lines
717 B
Java
28 lines
717 B
Java
// concurrent/SynchronizedConstructor.java
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// (c)2017 MindView LLC: see Copyright.txt
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// We make no guarantees that this code is fit for any purpose.
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// Visit http://OnJava8.com for more book information.
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import java.util.concurrent.atomic.*;
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class SyncConstructor implements HasID {
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private final int id;
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private static Object constructorLock = new Object();
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public SyncConstructor(SharedArg sa) {
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synchronized(constructorLock) {
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id = sa.get();
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}
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}
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@Override
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public int getID() { return id; }
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}
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public class SynchronizedConstructor {
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public static void main(String[] args) {
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Unsafe unsafe = new Unsafe();
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IDChecker.test(() -> new SyncConstructor(unsafe));
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}
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}
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/* Output:
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0
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*/
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