31 lines
796 B
Java
31 lines
796 B
Java
// lowlevel/MutexEvenProducer.java
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// (c)2020 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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// Preventing thread collisions with mutexes
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import java.util.concurrent.locks.*;
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import onjava.Nap;
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public class MutexEvenProducer extends IntGenerator {
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private int currentEvenValue = 0;
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private Lock lock = new ReentrantLock();
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@Override
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public int next() {
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lock.lock();
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try {
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++currentEvenValue;
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new Nap(0.01); // Cause failure faster
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++currentEvenValue;
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return currentEvenValue;
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} finally {
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lock.unlock();
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}
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}
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public static void main(String[] args) {
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EvenChecker.test(new MutexEvenProducer());
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}
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}
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/*
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No odd numbers discovered
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*/
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