56 lines
1.7 KiB
Java
56 lines
1.7 KiB
Java
// concurrency/DeadlockingDiningPhilosophers.java
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// (c)2016 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://mindviewinc.com/Books/OnJava/ for more book information.
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// Demonstrates how deadlock can be hidden in a program.
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// {Args: 0 5 timeout}
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import java.util.concurrent.*;
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public class DeadlockingDiningPhilosophers {
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public static void main(String[] args) throws Exception {
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int ponder = 5;
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if(args.length > 0)
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ponder = Integer.parseInt(args[0]);
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int size = 5;
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if(args.length > 1)
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size = Integer.parseInt(args[1]);
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ExecutorService exec = Executors.newCachedThreadPool();
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Chopstick[] sticks = new Chopstick[size];
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for(int i = 0; i < size; i++)
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sticks[i] = new Chopstick();
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for(int i = 0; i < size; i++)
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exec.execute(new Philosopher(
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sticks[i], sticks[(i+1) % size], i, ponder));
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if(args.length == 3 && args[2].equals("timeout"))
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TimeUnit.SECONDS.sleep(5);
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else {
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System.out.println("Press 'Enter' to quit");
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System.in.read();
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}
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exec.shutdownNow();
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}
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}
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/* Output: (First and last 10 Lines)
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Philosopher 1 thinking
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Philosopher 1 grabbing right
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Philosopher 1 grabbing left
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Philosopher 1 eating
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Philosopher 1 thinking
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Philosopher 3 thinking
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Philosopher 4 thinking
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Philosopher 2 thinking
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Philosopher 1 grabbing right
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Philosopher 0 thinking
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________...________...________...________...________
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Philosopher 3 grabbing left
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Philosopher 2 grabbing left
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Philosopher 0 grabbing left
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Philosopher 4 grabbing left
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Philosopher 1 grabbing left
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Philosopher 3 exiting via interrupt
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Philosopher 4 exiting via interrupt
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Philosopher 1 exiting via interrupt
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Philosopher 0 exiting via interrupt
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Philosopher 2 exiting via interrupt
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*/
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