50 lines
1.1 KiB
Java
50 lines
1.1 KiB
Java
//: concurrency/ExplicitCriticalSection.java
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// ©2015 MindView LLC: see Copyright.txt
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// {ThrowsException} on a multiprocessor machine
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// Using explicit Lock objects to create critical sections.
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package concurrency;
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import java.util.concurrent.locks.*;
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// Synchronize the entire method:
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class ExplicitPairManager1 extends PairManager {
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private Lock lock = new ReentrantLock();
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@Override
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public void increment() {
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lock.lock();
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try {
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p.incrementX();
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p.incrementY();
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store(getPair());
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} finally {
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lock.unlock();
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}
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}
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}
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// Use a critical section:
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class ExplicitPairManager2 extends PairManager {
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private Lock lock = new ReentrantLock();
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@Override
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public void increment() {
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Pair temp;
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lock.lock();
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try {
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p.incrementX();
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p.incrementY();
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temp = getPair();
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} finally {
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lock.unlock();
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}
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store(temp);
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}
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}
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public class ExplicitCriticalSection {
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public static void main(String[] args) throws Exception {
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PairManager
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pman1 = new ExplicitPairManager1(),
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pman2 = new ExplicitPairManager2();
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CriticalSection.testApproaches(pman1, pman2);
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}
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} ///:~
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