34 lines
1.1 KiB
Java
34 lines
1.1 KiB
Java
// concurrent/DiningPhilosophers.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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// Hidden deadlock
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// {ValidateByHand} Gradle has trouble
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import java.util.*;
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import java.util.concurrent.*;
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import onjava.Nap;
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public class DiningPhilosophers {
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private StickHolder[] sticks;
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private Philosopher[] philosophers;
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public DiningPhilosophers(int n) {
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sticks = new StickHolder[n];
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Arrays.setAll(sticks, i -> new StickHolder());
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philosophers = new Philosopher[n];
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Arrays.setAll(philosophers, i ->
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new Philosopher(i,
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sticks[i], sticks[(i + 1) % n])); // [1]
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// Fix by reversing stick order for this one:
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// philosophers[1] = // [2]
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// new Philosopher(0, sticks[0], sticks[1]);
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Arrays.stream(philosophers)
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.forEach(CompletableFuture::runAsync); // [3]
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}
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public static void main(String[] args) {
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// Returns right away:
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new DiningPhilosophers(5); // [4]
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// Keeps main() from exiting:
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new Nap(3, "Shutdown");
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}
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}
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