[Programming Problem] The Dining Philosophers

Solution here is to add some `ordering` on the resources (i.e. forks) requested by the processes (i.e. the philosophers).
Identify the resource id’s (or fork id’s) that a philosopher is surround with
We make sure the process requests the `lower` id fork before the `higher` id fork to avoid deadlocks
Identify which fork (left or right) is the lower id fork and request in that order (i.e. first left then right first right then left)
Make sure mutex’s are held until forks are released

class DiningPhilosophers {
 
    private static ReentrantLock[] mutex = new ReentrantLock[] {
        new ReentrantLock(),
        new ReentrantLock(),
        new ReentrantLock(),
        new ReentrantLock(),
        new ReentrantLock(),
    };
 
    public DiningPhilosophers() {
 
    }
 
    // call the run() method of any runnable to execute its code
    public void wantsToEat(int philosopher,
                           Runnable pickLeftFork,
                           Runnable pickRightFork,
                           Runnable eat,
                           Runnable putLeftFork,
                           Runnable putRightFork) throws InterruptedException {
 
        int left = philosopher;
        int right = (philosopher-1) == -1 ? 4 : philosopher-1;
 
        if (Math.min(left, right) == left) {
 
            DiningPhilosophers.mutex[left].lock();
            DiningPhilosophers.mutex[right].lock();
            pickLeftFork.run();
            pickRightFork.run();
 
        } else {
 
            DiningPhilosophers.mutex[right].lock();
            DiningPhilosophers.mutex[left].lock();
            pickRightFork.run();
            pickLeftFork.run();
 
        }
 
 
        eat.run();
 
        putLeftFork.run();
        putRightFork.run();
        DiningPhilosophers.mutex[left].unlock();
        DiningPhilosophers.mutex[right].unlock();
    }
}

[Programming Problem] The Dining Philosophers

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