OnJava8-Examples/concurrency/FixedDiningPhilosophers.java
2015-12-15 11:47:04 -08:00

60 lines
1.8 KiB
Java

// concurrency/FixedDiningPhilosophers.java
// (c)2016 MindView LLC: see Copyright.txt
// We make no guarantees that this code is fit for any purpose.
// Visit http://mindviewinc.com/Books/OnJava/ for more book information.
// Dining philosophers without deadlock.
// {Args: 5 5 timeout}
import java.util.concurrent.*;
public class FixedDiningPhilosophers {
public static void main(String[] args) throws Exception {
int ponder = 5;
if(args.length > 0)
ponder = Integer.parseInt(args[0]);
int size = 5;
if(args.length > 1)
size = Integer.parseInt(args[1]);
ExecutorService exec = Executors.newCachedThreadPool();
Chopstick[] sticks = new Chopstick[size];
for(int i = 0; i < size; i++)
sticks[i] = new Chopstick();
for(int i = 0; i < size; i++)
if(i < (size-1))
exec.execute(new Philosopher(
sticks[i], sticks[i+1], i, ponder));
else
exec.execute(new Philosopher(
sticks[0], sticks[i], i, ponder));
if(args.length == 3 && args[2].equals("timeout"))
TimeUnit.SECONDS.sleep(5);
else {
System.out.println("Press 'Enter' to quit");
System.in.read();
}
exec.shutdownNow();
}
}
/* Output: (First and last 10 Lines)
Philosopher 4 thinking
Philosopher 3 thinking
Philosopher 0 thinking
Philosopher 2 thinking
Philosopher 1 thinking
Philosopher 4 grabbing right
Philosopher 1 grabbing right
Philosopher 2 grabbing right
Philosopher 2 grabbing left
Philosopher 0 grabbing right
________...________...________...________...________
Philosopher 2 grabbing right
Philosopher 1 exiting via interrupt
Philosopher 0 exiting via interrupt
Philosopher 3 exiting via interrupt
Philosopher 4 grabbing right
Philosopher 2 grabbing left
Philosopher 4 grabbing left
Philosopher 2 exiting via interrupt
Philosopher 4 eating
Philosopher 4 exiting via interrupt
*/