class Feast { private static final int numberOfPhilosophers = 5; private static final Random random = new Random(); private static final Semaphore doorman = new Semaphore(4, true); private static final Stick[] sticks = new Stick[5]; public static void main(String[] args) {         for (int i = 0; i < 5; i++) sticks[i] = new Stick();         Philosopher[] philosophers = new Philosopher[numberOfPhilosophers];        for (int i = 0; i < 5; i++) {             philosophers[i] = new Philosopher(i);             philosophers[i].start();         } } static class Philosopher extends Thread {         private final Stick left, right;         Philosopher(int number) {             super("Philosopher" + number);             right = sticks[number];             left = sticks[(number + 1) % numberOfPhilosophers];        }       void meditate() throws InterruptedException {             System.out.println(getName() + " is meditating"); sleep(random.nextInt(10000));             System.out.println(getName() + " has finished meditating");             eat();         }         void eat() throws InterruptedException { doorman.acquire();             left.take();             right.take();             System.out.println(getName() + " is eating"); sleep(random.nextInt(10000));             left.release();             right.release(); doorman.release();             meditate();         }         @Override         public void run() {             try {                 meditate();             } catch (InterruptedException e) {                 e.printStackTrace();             }         }   } }

import java.util.concurrent.Semaphore; class Stick { private final Semaphore available = new Semaphore(1); void take() throws InterruptedException {         available.acquire(); } void release() {         available.release(); } }